Speed vs Tempreture and a tale of frustration.
Posted by Mongrel_Shark
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Speed vs Tempreture and a tale of frustration. September 13, 2016 07:00AM |
Ok This should hopefully be the thread that finally sorts out all my printing issues. Of which there have been many over the last 6 weeks.
After having issues with broken nozzles and no money to replace and home made nozzles and slipping z screws combined with acceleration problems loose belts, wobbly z axis etc etc.. I have finally started getting a few decent prints. Not perfect, but prints I am really happy with considering the (cheap/handmade) quality of most of my printer parts.
These are all things I tried to print before but failed miserably at. I'm really happy to be able to print some basic ready assembled moving parts
Also I can now pretty much just click print and it all goes according to plan.
Until I changed colour...
I should mention at this point, for those that haven’t seen the other two threads I made. That the whole time I have had problems printing slowly.
Every guide and bit of advice I have had says print slower first. Makes sense too. Except it never worked out. I tried and tried, but the best prints always happened at higher speeds.
I spent the first 3 weeks printing at sub 40mm/s speeds and got horrible results. First layers an inch off the bed, huge layer gaps. inconsistent extrusion. I was constantly pausing and winding Z's by hand and all sorts of not recommended stuff (like blowtorch heat supplementation, don't panic, I'm a trained professional and didn't kill or damage anything. Don't blowtorch your bed or nozzle though. its a stupid idea.) to nurse it along. Then one day I started clicking the speed percentage up in pronterface, Out of pure frustration. Got some popcorn and sat back waiting for it to print even worse or crash and burn. I just didn't care any-more.. 300% speed lets go!
Except it didn't screw up! It was the best print I had done. It was still crap, but to me it was beautiful. It actually resembled the .stl I had sliced and wasn't another FSM.
So I chased up temperature issues. Because that seemed to be the most probable cause. Why else would a nozzle not extrude consistently when printing slow, but go great at speeds over 100mm/s??
Except I had the same problem at every temp sugested. Using a k-probe via DMM to check a not very trustworth thermistor. If I printed my ABS at 230. it didn't extrude at all. 240 and it came out, but barely. 250 an it extrudes ok but banding and poor adhesion, splitting etc.
I got it printing what I though was pretty good after a few days of refining the hotend heating setup. Only to find any part over an inch high would curl and split catastrophically. Googling the solution to that I found a stack of other people print at 100mm/s+ and 160-180c. So thats where I have been printing and its been great.
Further help from this forum and the above parts where printed at mostly Slic3r default speeds. Aside from running the hotend at 270c (K-probe reading, 250 according to thermistor) Except top layer at 20mm/s infill at 120 and solid infil at 60-80. I can slow the infil down, but not the top layer. Go slower and the too hot nozzle boils the plastic and it gets all stringy, spiky and yuk. That was fine though I could top layer up to 40mm/s before it got holy. 20-30 was nice.
By this stage I'm assuming the 8 rolls of $20 ABS I got where $20 for a very good reason.... Unfortunately I can't get any more till I can sell some prints.... Facepalm.
I have stuff to sell too, the 8 rolls was advance payment for circus props for eg. Also getting a bit hungry at this stage. My start a printing business at home plans only included 3-4 weeks of calibration tuning time... Not 6-8 weeks its taken so far. I have been doing 18-20 hours a day on this craptastic catastrophe... (the sort version of a longer saga is I am no longer sick enough to get a disability pension, but not yet well enough to get unemployment assistance. I have exhaustion/reliability issues so working from home makes sense and I'm pretty good with tech etc. This printing caper is the best of a bunch of poor options. This is not the only printer I have but the other one is out on loan until I get fuel money)
Anyway. No matter. I can print stuff just good enough to sell and don't mind doing a bit of sanding or acetone vapour. I was all good. Everything was great. I was back on schedule.
Then I changed colour.....
It went well at first.
I printed the cone first. Because High Vis orrange. It had to be done.
It was a pretty poor print. Obviously my e-step needed a tweak to the new filament (following the Triffid Hunter guide). The cone has been sanded and fogged after I printed it.
So thinking I am pretty familliar with my rig by this stage I just guestimated it up 3 steps per mm. Printed the big bunny (scaled 200%=60mm high) next. Less under extrusion but still a bit to go. It'll fog up ok.
Still running 270c at this stage. Pretty close to slic3r default speeds. Maybe a touch faster, because I could, not because I had to.
The chain was next and not great, but I know how to improve that a lot next time. Its a tricky print. The main issue was bridging too hot/slow and lack of air from fan caused a lot of edge curl on overhangs on the leeward side. (Yes, the fan can help prevent some curling if used in moderation and aimed well. At least for me, I understand this may not be common for ABS, its a result of trial and error, you only want a tiny bit of air in the extrusion zone and no lower. I couldn't overhang at all without a fan. It just curled up)
So I upped the e-step a couple more. from E424.5 on dark blue I was now up to 429 still at default speeds and 270c. 130c bed, which is spot on according to the favourite beverage test in the triffid hunter guide. The parts can /bendwarp a little if removed at 130, but are fully hard at around 110.
Then I printed some carabiners to go with the chain
Looking at the macro pics on my big monitor I can now see I was still a bit low on e-setps but otherwise pretty good. Very happy with the finish.
Next was a t-rex peg thingy.
again mostly happy. top layer a bit holey but otherwise good. Bumped up e-steps to 430.
Then it was bed time and I left these to go overnight
Again mostly happy. Slight under extrusion but nothing hard to fix. The gears all turn after a little scalpel work on the bottom where the ABS juice was.
also a little elliptical holing, Y belt got a makshift zip tie tensioner till I can print a better one. (it'll probably still have zip ties a year from now if they keep working)
So I'm thinking better do the steps again. Its only an hour and a half and they make a good display piece if the come out well.
It was going great. Dialled in the e-steps perfectly to 432 before the first row of steps was done (I do 10 top layers on this test). Was almost going to stop it there and load up a big bed full of stuff so I could get some housework done. But I let it go, had coffee etc.
Then his happened on the top step.
The infill went down great. Its just the perimeter. I know what your thinking about this point and your at least half right if you think its slic3r and the whole short layer time problem. That was the catalyst I think. but not the whole problem. I thought that was all it was. No drama I'm thinking. I just print multiple tall skinny things as a temporary workaround until I get other slicing software running (still have matter control downloaded on both computers and ready to install)
So I load up the big bed of high vis junk I want to print. Gears, thumb wheels ets.
Except the first layer is now too slow and its just dropping little dry looking speck that don’t flow or stick. Just like the top of the steps. The skirt and longer sides of some parts went well, but once it tried to do an m3 nut hole that was it blocked nozzle.
So i cleaned it all out and got it flowing good and tried again. Same thing. Rinse and repeat another 3-4 times. Extrudes nice until fine detail bits. Then blocks up.
I'm back to the temperature blues again
So I sliced the most troublesome part on its own and started playing with temp settings.
(The lens is good, its the parts that are bury
)
After 20-30 starts at every temp I could think of from 220-280 I found I could sort of print at a much more reasonable 235-240. But its still not extruding consistantly. Where before I had at least +/- 5c to play with. Now I have about +/- 1.5c and my hardware is just not that good.
Whats really messing with me though. Is I didn't change anything.
I have considered weather. It was a warm morning. 28c vs 18c the night before. Humidity hasn't changed noticeably (my meters on the pile of stuff that needs fixing, its a big pile) I can see that having some effect, but this much? It makes no sense.
Its not getting blocked so much as just not extruding little bits slowly. (Turning retraction off helped but not a lot and its messy)
I can't extrude slowly again. I'm getting really frustrated with this problem. It just keeps happening. 3 difference rolls of filament. I can print at 120mm/s disturbinly well considering the flimsy printer construction. but 3 small perimiters with retractions in a row and it stops extruding untill I use pronterface to make it extrude at 250mm/m
Once its flowing I can air extrude down to about 50mm/m then it starts spotting and stops.
So bad filament??? Any input would be useful at this point.
To save questions I'll try and list all my gear/setting again below.
Homemade i3 prusa, shabby but has worked well at times.
RAMPS with a4988's
Heated bed. running 130c which is about right according to every calibration guide I have read (mostly on reprap wiki) and my testing acording to these instructions.
Not sure on the extruder, maybe a wades? Its a POC!! Its a geared hobbed bolt affair. It likes to slip, and I did have to tighten things repetadly after changing to orange. As well as had to up the current by 20%. Reasonably sure its not slipping now and still cant print slow. will double check it again next time I try to print. I have a duel drive replacement I printed last week. just need to find some 11mm rod to machine and hob up for drive gears. The current hobbed bolt is clean and not clogged.
Photo of the extruder in this thread [forums.reprap.org]
Yes thats a big fan. probably too big. Its not the problem though as no changes made until after lack of extrusion. changing fan aim or speed made little or no benifical difference. Doing silly stuff like pointing it low had the predictable result of over cooling the hotend and print.
Printing no-name (seller claimed SUN Label has batch numbers and looks industry grade) 3mm ABS with 220-260c on the label. It was vacuum sealed with silica until I opened it yesterday. No signs of moisture. I doesn't melt right in acetone ABS juice though. White solid (but soft, if that makes sense) bits in the bottom of the jar. Some black specks also in the juice, but likely from my brush and the black I was using 2 weeks back.
Been printing at 270-280c as a result of trial and error.
Speeds Mostly around:
60-80mm/s perimiter.
20mm small perim
ext perim 50%
infil 80mm/s
solid infil 50mm
top solid 20mm This works fine once its covering some distance. Its the small perim thats causing blockage/lack of flow. Solid and top layers usually unblock it if I let it go after a blockage.
First layer 50%
non travel 170
retraction either off or 2mm. sometimes I run 0.0something under 5 extra length. If its under extruding after retract. Maybe I should turn that up and see if it helps? Seems like it might. I was running 0.2-0.5 last lime I had this problem and it went away for a bit then later it was over extruding after retracts so been slowly dialing it back again.
I think that’s all the common questions covered.
As I write all this out I'm thinking more and more its bad filament. With not enough plasticiser. I can't get more filament, so I will have to make some plasticiser with what I have.
What plasticisers have people here used in these situations? My chemistry sucks, but maybe detergent or glycerol? Or Borax? Silicon spray? I guess I should ask my chemist mate. I suspect no one here will have tried extra plasticiser... Has anyone tried the oily rag trick with acetone? Probably a bad idea with my ABS extruder’s... Lol, yea that’s a really bad idea. Although I could probably rig an injector into the ally hotend thingymajiggy
Anyway I'm really tired and frustrated with this can't print slow business. So I'm going to bed early tonight and fixing all the crappy mechanical stuff on the printer tomorrow. Well as much as I can without printing the extra parts I want. Maybe even make an enclosure I have some bracing ply and 2x1.... Hopefully someone will have some fresh ideas by then
Cheers
Mong
If you can't fix it with tape and tie wire. Its broken. You need a new one.
[www.youtube.com]
[plus.google.com]
Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
After having issues with broken nozzles and no money to replace and home made nozzles and slipping z screws combined with acceleration problems loose belts, wobbly z axis etc etc.. I have finally started getting a few decent prints. Not perfect, but prints I am really happy with considering the (cheap/handmade) quality of most of my printer parts.
These are all things I tried to print before but failed miserably at. I'm really happy to be able to print some basic ready assembled moving parts
Also I can now pretty much just click print and it all goes according to plan.Until I changed colour...
I should mention at this point, for those that haven’t seen the other two threads I made. That the whole time I have had problems printing slowly.
Every guide and bit of advice I have had says print slower first. Makes sense too. Except it never worked out. I tried and tried, but the best prints always happened at higher speeds.
I spent the first 3 weeks printing at sub 40mm/s speeds and got horrible results. First layers an inch off the bed, huge layer gaps. inconsistent extrusion. I was constantly pausing and winding Z's by hand and all sorts of not recommended stuff (like blowtorch heat supplementation, don't panic, I'm a trained professional and didn't kill or damage anything. Don't blowtorch your bed or nozzle though. its a stupid idea.) to nurse it along. Then one day I started clicking the speed percentage up in pronterface, Out of pure frustration. Got some popcorn and sat back waiting for it to print even worse or crash and burn. I just didn't care any-more.. 300% speed lets go!
Except it didn't screw up! It was the best print I had done. It was still crap, but to me it was beautiful. It actually resembled the .stl I had sliced and wasn't another FSM.
So I chased up temperature issues. Because that seemed to be the most probable cause. Why else would a nozzle not extrude consistently when printing slow, but go great at speeds over 100mm/s??
Except I had the same problem at every temp sugested. Using a k-probe via DMM to check a not very trustworth thermistor. If I printed my ABS at 230. it didn't extrude at all. 240 and it came out, but barely. 250 an it extrudes ok but banding and poor adhesion, splitting etc.
I got it printing what I though was pretty good after a few days of refining the hotend heating setup. Only to find any part over an inch high would curl and split catastrophically. Googling the solution to that I found a stack of other people print at 100mm/s+ and 160-180c. So thats where I have been printing and its been great.
Further help from this forum and the above parts where printed at mostly Slic3r default speeds. Aside from running the hotend at 270c (K-probe reading, 250 according to thermistor) Except top layer at 20mm/s infill at 120 and solid infil at 60-80. I can slow the infil down, but not the top layer. Go slower and the too hot nozzle boils the plastic and it gets all stringy, spiky and yuk. That was fine though I could top layer up to 40mm/s before it got holy. 20-30 was nice.
By this stage I'm assuming the 8 rolls of $20 ABS I got where $20 for a very good reason.... Unfortunately I can't get any more till I can sell some prints.... Facepalm.
I have stuff to sell too, the 8 rolls was advance payment for circus props for eg. Also getting a bit hungry at this stage. My start a printing business at home plans only included 3-4 weeks of calibration tuning time... Not 6-8 weeks its taken so far. I have been doing 18-20 hours a day on this craptastic catastrophe... (the sort version of a longer saga is I am no longer sick enough to get a disability pension, but not yet well enough to get unemployment assistance. I have exhaustion/reliability issues so working from home makes sense and I'm pretty good with tech etc. This printing caper is the best of a bunch of poor options. This is not the only printer I have but the other one is out on loan until I get fuel money)
Anyway. No matter. I can print stuff just good enough to sell and don't mind doing a bit of sanding or acetone vapour. I was all good. Everything was great. I was back on schedule.
Then I changed colour.....
It went well at first.
I printed the cone first. Because High Vis orrange. It had to be done.
It was a pretty poor print. Obviously my e-step needed a tweak to the new filament (following the Triffid Hunter guide). The cone has been sanded and fogged after I printed it.
So thinking I am pretty familliar with my rig by this stage I just guestimated it up 3 steps per mm. Printed the big bunny (scaled 200%=60mm high) next. Less under extrusion but still a bit to go. It'll fog up ok.
Still running 270c at this stage. Pretty close to slic3r default speeds. Maybe a touch faster, because I could, not because I had to.
The chain was next and not great, but I know how to improve that a lot next time. Its a tricky print. The main issue was bridging too hot/slow and lack of air from fan caused a lot of edge curl on overhangs on the leeward side. (Yes, the fan can help prevent some curling if used in moderation and aimed well. At least for me, I understand this may not be common for ABS, its a result of trial and error, you only want a tiny bit of air in the extrusion zone and no lower. I couldn't overhang at all without a fan. It just curled up)
So I upped the e-step a couple more. from E424.5 on dark blue I was now up to 429 still at default speeds and 270c. 130c bed, which is spot on according to the favourite beverage test in the triffid hunter guide. The parts can /bendwarp a little if removed at 130, but are fully hard at around 110.
Then I printed some carabiners to go with the chain
Looking at the macro pics on my big monitor I can now see I was still a bit low on e-setps but otherwise pretty good. Very happy with the finish.
Next was a t-rex peg thingy.
again mostly happy. top layer a bit holey but otherwise good. Bumped up e-steps to 430.
Then it was bed time and I left these to go overnight
Again mostly happy. Slight under extrusion but nothing hard to fix. The gears all turn after a little scalpel work on the bottom where the ABS juice was.
also a little elliptical holing, Y belt got a makshift zip tie tensioner till I can print a better one. (it'll probably still have zip ties a year from now if they keep working)
So I'm thinking better do the steps again. Its only an hour and a half and they make a good display piece if the come out well.
It was going great. Dialled in the e-steps perfectly to 432 before the first row of steps was done (I do 10 top layers on this test). Was almost going to stop it there and load up a big bed full of stuff so I could get some housework done. But I let it go, had coffee etc.
Then his happened on the top step.
The infill went down great. Its just the perimeter. I know what your thinking about this point and your at least half right if you think its slic3r and the whole short layer time problem. That was the catalyst I think. but not the whole problem. I thought that was all it was. No drama I'm thinking. I just print multiple tall skinny things as a temporary workaround until I get other slicing software running (still have matter control downloaded on both computers and ready to install)
So I load up the big bed of high vis junk I want to print. Gears, thumb wheels ets.
Except the first layer is now too slow and its just dropping little dry looking speck that don’t flow or stick. Just like the top of the steps. The skirt and longer sides of some parts went well, but once it tried to do an m3 nut hole that was it blocked nozzle.
So i cleaned it all out and got it flowing good and tried again. Same thing. Rinse and repeat another 3-4 times. Extrudes nice until fine detail bits. Then blocks up.
I'm back to the temperature blues again
So I sliced the most troublesome part on its own and started playing with temp settings.
)After 20-30 starts at every temp I could think of from 220-280 I found I could sort of print at a much more reasonable 235-240. But its still not extruding consistantly. Where before I had at least +/- 5c to play with. Now I have about +/- 1.5c and my hardware is just not that good.
Whats really messing with me though. Is I didn't change anything.
I have considered weather. It was a warm morning. 28c vs 18c the night before. Humidity hasn't changed noticeably (my meters on the pile of stuff that needs fixing, its a big pile) I can see that having some effect, but this much? It makes no sense.
Its not getting blocked so much as just not extruding little bits slowly. (Turning retraction off helped but not a lot and its messy)
I can't extrude slowly again. I'm getting really frustrated with this problem. It just keeps happening. 3 difference rolls of filament. I can print at 120mm/s disturbinly well considering the flimsy printer construction. but 3 small perimiters with retractions in a row and it stops extruding untill I use pronterface to make it extrude at 250mm/m
Once its flowing I can air extrude down to about 50mm/m then it starts spotting and stops.
So bad filament??? Any input would be useful at this point.
To save questions I'll try and list all my gear/setting again below.
Homemade i3 prusa, shabby but has worked well at times.
RAMPS with a4988's
Heated bed. running 130c which is about right according to every calibration guide I have read (mostly on reprap wiki) and my testing acording to these instructions.
Not sure on the extruder, maybe a wades? Its a POC!! Its a geared hobbed bolt affair. It likes to slip, and I did have to tighten things repetadly after changing to orange. As well as had to up the current by 20%. Reasonably sure its not slipping now and still cant print slow. will double check it again next time I try to print. I have a duel drive replacement I printed last week. just need to find some 11mm rod to machine and hob up for drive gears. The current hobbed bolt is clean and not clogged.
Photo of the extruder in this thread [forums.reprap.org]
Yes thats a big fan. probably too big. Its not the problem though as no changes made until after lack of extrusion. changing fan aim or speed made little or no benifical difference. Doing silly stuff like pointing it low had the predictable result of over cooling the hotend and print.
Printing no-name (seller claimed SUN Label has batch numbers and looks industry grade) 3mm ABS with 220-260c on the label. It was vacuum sealed with silica until I opened it yesterday. No signs of moisture. I doesn't melt right in acetone ABS juice though. White solid (but soft, if that makes sense) bits in the bottom of the jar. Some black specks also in the juice, but likely from my brush and the black I was using 2 weeks back.
Been printing at 270-280c as a result of trial and error.
Speeds Mostly around:
60-80mm/s perimiter.
20mm small perim
ext perim 50%
infil 80mm/s
solid infil 50mm
top solid 20mm This works fine once its covering some distance. Its the small perim thats causing blockage/lack of flow. Solid and top layers usually unblock it if I let it go after a blockage.
First layer 50%
non travel 170
retraction either off or 2mm. sometimes I run 0.0something under 5 extra length. If its under extruding after retract. Maybe I should turn that up and see if it helps? Seems like it might. I was running 0.2-0.5 last lime I had this problem and it went away for a bit then later it was over extruding after retracts so been slowly dialing it back again.
I think that’s all the common questions covered.
As I write all this out I'm thinking more and more its bad filament. With not enough plasticiser. I can't get more filament, so I will have to make some plasticiser with what I have.
What plasticisers have people here used in these situations? My chemistry sucks, but maybe detergent or glycerol? Or Borax? Silicon spray? I guess I should ask my chemist mate. I suspect no one here will have tried extra plasticiser... Has anyone tried the oily rag trick with acetone? Probably a bad idea with my ABS extruder’s... Lol, yea that’s a really bad idea. Although I could probably rig an injector into the ally hotend thingymajiggy
Anyway I'm really tired and frustrated with this can't print slow business. So I'm going to bed early tonight and fixing all the crappy mechanical stuff on the printer tomorrow. Well as much as I can without printing the extra parts I want. Maybe even make an enclosure I have some bracing ply and 2x1.... Hopefully someone will have some fresh ideas by then
Cheers
Mong
If you can't fix it with tape and tie wire. Its broken. You need a new one.
[www.youtube.com]
[plus.google.com]
Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
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Re: Speed vs Tempreture and a tale of frustration. September 13, 2016 07:53AM |
Not 5 min after I clicked post on that huge saga....
I thought I'd re print some of the last fer g.codes to see if day vs night temps really had that much effect.
The motor was squawking but the gears weren’t turning.
Could this be related to my problem??
Facepalm.
I dont have a spare. I'll try ABS goop or drill out other side untill I can get my duel extruder going....
Maybe that will help?
I thought I'd re print some of the last fer g.codes to see if day vs night temps really had that much effect.
The motor was squawking but the gears weren’t turning.
Could this be related to my problem??
Facepalm.
I dont have a spare. I'll try ABS goop or drill out other side untill I can get my duel extruder going....
Maybe that will help?
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Re: Speed vs Tempreture and a tale of frustration. September 13, 2016 07:37PM |
So many suggestions and not one I haven't already looked into 
:
Thanks to everyone for helping though
. Its worth going over basic obvious stuff. because I do feel like I'm missing something. Something blatant and obvious that should be smacking me in the face.
The heat cartridge and thermistor are seated well.
The thermistor is consistent. it just has a margin of error that is normal for a ~+/-10% thermistor 250c=25c margin of error, exactly what I have observed..... Its a consistent margin of error. I've been monitoring it closely because I hate using them for anything that requires more than +/- 10c accuracy. Especially at temps over 100c. My electronics teacher warned me about such problems 25 years ago and I have seen it many times since He would never use one in any of his transmitters, except as a rough back up for safety disconnect. They are slow (to conduct heat, 2 sec lag is as good as they get) and inaccurate and change with age and use (they may have gotten better with time, but I will never trust them). Hence why I got a K-probe setup with the kit. Unfortunately my coding skills are not up to sorting out the i2C disaster in Marlin. Not that I want to run it on i2c anyway. I don't see that working out at all. I'd really like to increase temp readings to 5 times a sec rather than the once a sec it is now. I'd also like to redesign a better heatblock with the k-probe in a better spot, better taper inside and look at airtight filament seal (that’s a big ask, but not impossible). Very tempted to have a second smaller arduino for heat control all on its own and another for rotary encoders to look for bad steps. But none of that is here or now....
The heat inconsistency in in the aluminium heat block, and is perfectly normal for that material running that temp in open air. I had predicted as much the first time I saw a picture of one. Its a good conductor of heat. Its just doing its job and dissipating heat to the air as fast as it can. I should take my own advice from another thread and insulate it from the air some more as part of todays tear down maintenance. Rough napkin maths tells me 40-60% of the wattage going to the heater is passing to the surrounding air rather than the plastic to be melted. Maybe more. I've been meaning to measure its efficiency. It seems worse than I predicted...
I checked my g-code. all extrusions are 0.4 or higher. and obviously it wouldn’t have changed the extrusion size for the last step in the stairs. I have never once printed that top step! Been blaming slicer, but its becoming obvious that’s not the whole problem. I have been doing a lot of 0.5-0.6 too, but need 0.4 to make printer parts... So that’s why I was calibrating at that size. I too like to set the sizes in slicers advanced tab. Because it does indeed do strange things sometimes.
I did mention I have been printing new parts.... I like to calibrate a new filament first though. Before trying to print precision parts... I was running low on the blue so couldn't keep dong that. Making metal or nylon parts is all part of the longer term plan. I agree 100% that plastic parts won't last. Thats why I printed lots of spare gears for the new extruder. I don't have a lathe or cnc (until I print some bits) so making good metal gears at home is not a realistic option yet. An ally casting setup and cnc mill is under construction, waiting for some cash to be thrown at it. I've taken it all as far as I can with hard rubbish parts. Printing useless parts is also partly for display at local bearing shop and on website etc too. So I can get work... and some are already sold! Because I need cash more than anything right now. So not so useless.
The current extruder is obviously not capable of getting a good grip. That's why one of the first things I printed was a mk8 gear duel drive model.... I have its clamp really tight though and it was stalling on low temp extrusion until I upped the current and broke the gear. Did I mention stripping filament?? Its not something I have had a serious problem with since the first few days of using this printer.. Maybe a few times, but I always knew why and it was mostly loose gripper bearing.
I did obviously over tighten the grub screw, but only in an attempt to stop the motor shaft spinning on low speed extrusions. It was going fine for the faster stuff, which I find very very odd. To reproduce the slippage I had to turn manual extrusion speed in pronterface down below 50mm/m. otherwise It was extruding great.
If it was going to not extrude at higher speed the motor would stall. I guess it has a lot more torque at lower speeds....
But what would cause the filament to extrude better fast than slow?? I keep coming back to this problem. 3 rolls of filament, all of which liked a different (but still a bit on the high side) temp ranges? I keep thinking bad filament, but I do feel like I'm missing something that should be very obvious. It just doesn't add up.
as to the e-step cal. I was originally of the same school of thought. get the e-steps calibrated right and change one of the other factors. But it wasn't working so I thought I should RTFM and follow the most highly recommended calibration guide on the internet [reprap.org]... Its actually not as silly as it seems and helped a lot. Pronterface won't let me adjust flow rate by less than 1%. Changing by half an e-step at a time got much much better results much much faster. I'd like to go back to "calibrating it properly" But the Triffid method is working for now and is easy to adjust so I'm not fixing it because it ain't broke.
Yes there is a ton of Z wobble as well as flex and play all over the place. Z screw is a crappy m6 rod with no bearing at the top (or anywhere). I never had any delusions of that working well. I did a video pointing that out and a few other traps for new players when the kit arrived. I'm amazed at the people that tell me I am wrong in the comments all the time. ie: "My printer runs zigzagged m5 rod and it prints to half a nano precision just fine, your an idiot" LMAO... The whole printer is a total abortion. I'm amazed I can print at the quality I have been. Cost me $50 on a lost bet with my partner who paid for all this stuff. I told him I couldn't work with this junk 2 years ago..... I'm assuming it only works this well because I'm such a top rate engineer
How it can print anything other than FSM's at 80-120mm/s is completely beyond me... The new parts will be made to run this M8 threaded rod I made ages ago. and will have either 2 stainless rods per side or run on angle or some other rail. My end goal is to have a printer stiff enough that I can interchange the extruder with a dremmal like tool for cutting PCB's. While having a work area big enough to make stormtrooper armour for cosplay fans. I haven’t seen anything around the internet that can do this, and was planning to design it (its mostly drafted in my head) but if anyone knows a really good Z&X setup I could copy/use/alter please do PM me a link. I'd rather not re-invent a wheel if there is already a good one out there, or at least study many existing wheels first. My other long term goal is to print at nano metre resolution for graphene hybrid batteries and solar cells etc. One step small at a time though....
Trying my best to keep this thread on topic. I think I addressed all the suggestions so far.
I'm still not understanding why I can only extrude well fast. I was thinking it was the high temps I kept resorting to causing jams in the crappy hotend shaft.
But that’s not adding up either. Even at lower temps, I still cant extrude slow and haven’t had to drill plastic blockages out of the hotend since I got the fan dialled in good..... I keep going back to hot and fast because that’s the only thing that works.
I've tried and tried to go cooler and slower as recommended, but it just does not work.
Despite a number of other minor issues. The number one problem I keep coming back to is the high print temps and high speeds are the only thing that works consistently..
Still concerned the filament is bad and don't know how to test it. I'm even thinking its got chemical inconsistency over the length of the roll. hence the sudden change with the orange. Although that sudden change was probably the grub screw failing....
Maybe that gear screw has been slipping for a while. I have noticed a few times that the gear didn't appear to be moving at lower speeds, but figure it was just going really slow as some of those times it was actually extruding ok. Maybe back pressure was maintaining small amounts of flow and maybe it's been intermittent??
Last night I first noticed it slipping, so tightened it. Then the motor was stalling so more current, up to about 70%. Can't go more without active cooling. Then the grub screw failed.... Looking closely at the pics I'm thinking the parts where printed a few c too cold. Layer bondage is barely adequate. I'll fog any other parts from that kit i think may be overstressed to strengthen the bondage. But thats not really the problem. The problem is I can't extrude slowly.
Here is a pic of my partly repaired gear. It still needs a few hours to dry. Then I'll acetone fog it to glaze it up harder and make sure my slurry bonds well to the original part. Its something I have been testing and got fairly refined.
I also have pics of my new extruder which I downloaded from here [www.thingiverse.com] All I need is the MK8 gears and its complete. I can't afford the gears or get them in less than 2 weeks if I could afford them, but I have some 11mm bolts I think I can hand machine with my drills... After screwing up a few hobbed bolts I got pretty good at it.
I'm going to go sort out some mechanical stuff and I'll be back later to see if anyone has any more ideas. Hopefully someone can think of something I've missed...
Edited 2 time(s). Last edit at 09/13/2016 07:46PM by Mongrel_Shark.
:Thanks to everyone for helping though
. Its worth going over basic obvious stuff. because I do feel like I'm missing something. Something blatant and obvious that should be smacking me in the face.The heat cartridge and thermistor are seated well.
The thermistor is consistent. it just has a margin of error that is normal for a ~+/-10% thermistor 250c=25c margin of error, exactly what I have observed..... Its a consistent margin of error. I've been monitoring it closely because I hate using them for anything that requires more than +/- 10c accuracy. Especially at temps over 100c. My electronics teacher warned me about such problems 25 years ago and I have seen it many times since He would never use one in any of his transmitters, except as a rough back up for safety disconnect. They are slow (to conduct heat, 2 sec lag is as good as they get) and inaccurate and change with age and use (they may have gotten better with time, but I will never trust them). Hence why I got a K-probe setup with the kit. Unfortunately my coding skills are not up to sorting out the i2C disaster in Marlin. Not that I want to run it on i2c anyway. I don't see that working out at all. I'd really like to increase temp readings to 5 times a sec rather than the once a sec it is now. I'd also like to redesign a better heatblock with the k-probe in a better spot, better taper inside and look at airtight filament seal (that’s a big ask, but not impossible). Very tempted to have a second smaller arduino for heat control all on its own and another for rotary encoders to look for bad steps. But none of that is here or now....
The heat inconsistency in in the aluminium heat block, and is perfectly normal for that material running that temp in open air. I had predicted as much the first time I saw a picture of one. Its a good conductor of heat. Its just doing its job and dissipating heat to the air as fast as it can. I should take my own advice from another thread and insulate it from the air some more as part of todays tear down maintenance. Rough napkin maths tells me 40-60% of the wattage going to the heater is passing to the surrounding air rather than the plastic to be melted. Maybe more. I've been meaning to measure its efficiency. It seems worse than I predicted...
I checked my g-code. all extrusions are 0.4 or higher. and obviously it wouldn’t have changed the extrusion size for the last step in the stairs. I have never once printed that top step! Been blaming slicer, but its becoming obvious that’s not the whole problem. I have been doing a lot of 0.5-0.6 too, but need 0.4 to make printer parts... So that’s why I was calibrating at that size. I too like to set the sizes in slicers advanced tab. Because it does indeed do strange things sometimes.
I did mention I have been printing new parts.... I like to calibrate a new filament first though. Before trying to print precision parts... I was running low on the blue so couldn't keep dong that. Making metal or nylon parts is all part of the longer term plan. I agree 100% that plastic parts won't last. Thats why I printed lots of spare gears for the new extruder. I don't have a lathe or cnc (until I print some bits) so making good metal gears at home is not a realistic option yet. An ally casting setup and cnc mill is under construction, waiting for some cash to be thrown at it. I've taken it all as far as I can with hard rubbish parts. Printing useless parts is also partly for display at local bearing shop and on website etc too. So I can get work... and some are already sold! Because I need cash more than anything right now. So not so useless.
The current extruder is obviously not capable of getting a good grip. That's why one of the first things I printed was a mk8 gear duel drive model.... I have its clamp really tight though and it was stalling on low temp extrusion until I upped the current and broke the gear. Did I mention stripping filament?? Its not something I have had a serious problem with since the first few days of using this printer.. Maybe a few times, but I always knew why and it was mostly loose gripper bearing.
I did obviously over tighten the grub screw, but only in an attempt to stop the motor shaft spinning on low speed extrusions. It was going fine for the faster stuff, which I find very very odd. To reproduce the slippage I had to turn manual extrusion speed in pronterface down below 50mm/m. otherwise It was extruding great.
If it was going to not extrude at higher speed the motor would stall. I guess it has a lot more torque at lower speeds....
But what would cause the filament to extrude better fast than slow?? I keep coming back to this problem. 3 rolls of filament, all of which liked a different (but still a bit on the high side) temp ranges? I keep thinking bad filament, but I do feel like I'm missing something that should be very obvious. It just doesn't add up.
as to the e-step cal. I was originally of the same school of thought. get the e-steps calibrated right and change one of the other factors. But it wasn't working so I thought I should RTFM and follow the most highly recommended calibration guide on the internet [reprap.org]... Its actually not as silly as it seems and helped a lot. Pronterface won't let me adjust flow rate by less than 1%. Changing by half an e-step at a time got much much better results much much faster. I'd like to go back to "calibrating it properly" But the Triffid method is working for now and is easy to adjust so I'm not fixing it because it ain't broke.
Yes there is a ton of Z wobble as well as flex and play all over the place. Z screw is a crappy m6 rod with no bearing at the top (or anywhere). I never had any delusions of that working well. I did a video pointing that out and a few other traps for new players when the kit arrived. I'm amazed at the people that tell me I am wrong in the comments all the time. ie: "My printer runs zigzagged m5 rod and it prints to half a nano precision just fine, your an idiot" LMAO... The whole printer is a total abortion. I'm amazed I can print at the quality I have been. Cost me $50 on a lost bet with my partner who paid for all this stuff. I told him I couldn't work with this junk 2 years ago..... I'm assuming it only works this well because I'm such a top rate engineer
How it can print anything other than FSM's at 80-120mm/s is completely beyond me... The new parts will be made to run this M8 threaded rod I made ages ago. and will have either 2 stainless rods per side or run on angle or some other rail. My end goal is to have a printer stiff enough that I can interchange the extruder with a dremmal like tool for cutting PCB's. While having a work area big enough to make stormtrooper armour for cosplay fans. I haven’t seen anything around the internet that can do this, and was planning to design it (its mostly drafted in my head) but if anyone knows a really good Z&X setup I could copy/use/alter please do PM me a link. I'd rather not re-invent a wheel if there is already a good one out there, or at least study many existing wheels first. My other long term goal is to print at nano metre resolution for graphene hybrid batteries and solar cells etc. One step small at a time though....Trying my best to keep this thread on topic
. I think I addressed all the suggestions so far.I'm still not understanding why I can only extrude well fast. I was thinking it was the high temps I kept resorting to causing jams in the crappy hotend shaft.
But that’s not adding up either. Even at lower temps, I still cant extrude slow and haven’t had to drill plastic blockages out of the hotend since I got the fan dialled in good..... I keep going back to hot and fast because that’s the only thing that works.
I've tried and tried to go cooler and slower as recommended, but it just does not work.
Despite a number of other minor issues. The number one problem I keep coming back to is the high print temps and high speeds are the only thing that works consistently..
Still concerned the filament is bad and don't know how to test it. I'm even thinking its got chemical inconsistency over the length of the roll. hence the sudden change with the orange. Although that sudden change was probably the grub screw failing....
Maybe that gear screw has been slipping for a while. I have noticed a few times that the gear didn't appear to be moving at lower speeds, but figure it was just going really slow as some of those times it was actually extruding ok. Maybe back pressure was maintaining small amounts of flow and maybe it's been intermittent??
Last night I first noticed it slipping, so tightened it. Then the motor was stalling so more current, up to about 70%. Can't go more without active cooling. Then the grub screw failed.... Looking closely at the pics I'm thinking the parts where printed a few c too cold. Layer bondage is barely adequate. I'll fog any other parts from that kit i think may be overstressed to strengthen the bondage. But thats not really the problem. The problem is I can't extrude slowly.
Here is a pic of my partly repaired gear. It still needs a few hours to dry. Then I'll acetone fog it to glaze it up harder and make sure my slurry bonds well to the original part. Its something I have been testing and got fairly refined.
I also have pics of my new extruder which I downloaded from here [www.thingiverse.com] All I need is the MK8 gears and its complete. I can't afford the gears or get them in less than 2 weeks if I could afford them, but I have some 11mm bolts I think I can hand machine with my drills... After screwing up a few hobbed bolts I got pretty good at it.
I'm going to go sort out some mechanical stuff and I'll be back later to see if anyone has any more ideas. Hopefully someone can think of something I've missed...
Edited 2 time(s). Last edit at 09/13/2016 07:46PM by Mongrel_Shark.
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Re: Speed vs Tempreture and a tale of frustration. September 13, 2016 07:58PM |
Oh. One other odd thing.
Does this ABS juice look funny? It's made from trimmed off skirts and air extrusions etc from the orange I am printing with.
The blue and black specs are probably introduced from my brush. I'll make another lot when I get the orange backed out of the extruder.
But that white sediment..... It will partially suspend (still kind of chunky) if I shake it up. Then it settles to this after 30 min or so.
Does this ABS juice look funny? It's made from trimmed off skirts and air extrusions etc from the orange I am printing with.
The blue and black specs are probably introduced from my brush. I'll make another lot when I get the orange backed out of the extruder.
But that white sediment..... It will partially suspend (still kind of chunky) if I shake it up. Then it settles to this after 30 min or so.
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Re: Speed vs Tempreture and a tale of frustration. September 13, 2016 10:36PM |
I think I may have found the root of the problem!!
It is definitely one of those should have been smacking me in the face level of obvious simple things!
Look at how I had the gear mounted on the motor shaft!
The grub screw was trying to grip a round section of shaft with no flat!!
That was never going to work out well!
I have no idea what possessed me to mount it like that?? I should have known better
I have ground a longer flat onto the motor shaft with a dremmal like rotary tool
Now the grub screw will be a lot less stressed and more effective.
It was probably gripping better at high speeds due to friction heating or something?? Slipping more at low speeds, maybe because of higher torque or something??
It was definitely a problem.
I bet I end up with reduced e-step calibration once its reassembled. 400 should be the magic number according to the maths. But I have been running a bit higher and having to change it with extrusion temp etc. I bet its been slipping at all speeds but slipping less at high speeds.
This could explain my extra length after retract, high temp issues, low speed problems and a bunch of other problems I have had.... Looks like I'm not going crazy after all. I was starting to wonder.
Just waiting on that ABS goop to dry really good before I re-assemble.
While I am waiting I thought I would snap some pics of the filament I removed from the extruder. For feedback, Also moderators please feel free to use any of my pics on the Wiki if they can be of benefit to others.
Ignore what may appear to be a stripped bit at the far end from the plug. That's where I removed the hobbed bolt with the filament in place. Hence a bit of grease discolouration. Its was not stripping the filament as far as I can tell.
Wondering if my grip is about right. There is a flat spot on one side, from the bearing that clamps the filament to the hobbed bolt. It was very hard to photograph clearly. Not sure how visible it will be on a small monitor. Its visible on my 40" but maybe only because I already knew it was there. Try zooming in if you cant see it.
Opposite to the flat spot there is clear hobbing imprint. That looks good to me.
At 90 deg from the flat and hob marks there is some white discoloured bulging where the filament was deformed buy high clamping pressure between the hobbed bolt and bearing. Is this a sign of too much pressure?
If you can't fix it with tape and tie wire. Its broken. You need a new one.
[www.youtube.com]
[plus.google.com]
Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
It is definitely one of those should have been smacking me in the face level of obvious simple things!
Look at how I had the gear mounted on the motor shaft!
The grub screw was trying to grip a round section of shaft with no flat!!
That was never going to work out well!
I have no idea what possessed me to mount it like that??
I should have known betterI have ground a longer flat onto the motor shaft with a dremmal like rotary tool
Now the grub screw will be a lot less stressed and more effective.
It was probably gripping better at high speeds due to friction heating or something?? Slipping more at low speeds, maybe because of higher torque or something??
It was definitely a problem.
I bet I end up with reduced e-step calibration once its reassembled. 400 should be the magic number according to the maths. But I have been running a bit higher and having to change it with extrusion temp etc. I bet its been slipping at all speeds but slipping less at high speeds.
This could explain my extra length after retract, high temp issues, low speed problems and a bunch of other problems I have had....
Looks like I'm not going crazy after all. I was starting to wonder.Just waiting on that ABS goop to dry really good before I re-assemble.
While I am waiting I thought I would snap some pics of the filament I removed from the extruder. For feedback, Also moderators please feel free to use any of my pics on the Wiki if they can be of benefit to others.
Ignore what may appear to be a stripped bit at the far end from the plug. That's where I removed the hobbed bolt with the filament in place. Hence a bit of grease discolouration. Its was not stripping the filament as far as I can tell.
Wondering if my grip is about right. There is a flat spot on one side, from the bearing that clamps the filament to the hobbed bolt. It was very hard to photograph clearly. Not sure how visible it will be on a small monitor. Its visible on my 40" but maybe only because I already knew it was there. Try zooming in if you cant see it.
Opposite to the flat spot there is clear hobbing imprint. That looks good to me.
At 90 deg from the flat and hob marks there is some white discoloured bulging where the filament was deformed buy high clamping pressure between the hobbed bolt and bearing. Is this a sign of too much pressure?
If you can't fix it with tape and tie wire. Its broken. You need a new one.
[www.youtube.com]
[plus.google.com]
Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
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Re: Speed vs Tempreture and a tale of frustration. September 14, 2016 12:52AM |
If I said 0.4 layers that was a typo. Haven't tried that since I was running the home made 1mm nozzle. I am mostly printing 0.1995 layers (0.2 not divisible by layer height) Have tried 0.25 with some success and 0.1 with great results.
Hot throat jams are very likely. Was having a lot of problems there when I first replaced to old style plastic hotend after it broke. Thats a good enough explanation to satisfy me.
And yep. Its half pulled apart now. fixing as much mechanical and electrical stuff as I can over the next few days. With the hope I can print a few parts to fix the rest as much as the cheap hardware will allow. Been having heatbed problems the whole time too. So re-wiring that while its pulled apart. Hoping verry much the mystery will be solved.
At some point I have to just call this one a fail and make a better printer though. If I fix everything that's wrong with this one, The only original parts left will be the Arduino, 5 motors and a heatbed.
I'm not pulling anyones leg. Feel free to have a laugh though. I know I will be once its all sorted. Already am a littleD
I must say though. I am amazed I got this far with the crappy parts. I think the total spend on this printer is around $270 AU. With enough left over rods etc for 2 more.
Its in the top 5 most amazing projects I have got working for next to nothing. Only reason its not top of the list is I did buy parts. Usually I don't. Have a look at my youtube... There is another printer half made with all recycled parts from hard rubbish collection. I have a spaceship engine I made from a tin can and a paperclip. Tesla Coils would on toilet paper rolls. Battery’s made from pencils, paper towel and foil.. Its just how I am. No money to spare but love building stuff.
If you can't fix it with tape and tie wire. Its broken. You need a new one.
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[plus.google.com]
Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
Quote
the_digital_dentist
Why does it extrude fast better than slow?
Maybe when filament is moving through the extruder fast the heat can't creep up the throat and cause it to jam...
With all the mechanical problems I think anything could happen. Once the mechanical stuff is sorted out you can try again and maybe all the mysteries will have disappeared.
Hot throat jams are very likely. Was having a lot of problems there when I first replaced to old style plastic hotend after it broke. Thats a good enough explanation to satisfy me.
And yep. Its half pulled apart now. fixing as much mechanical and electrical stuff as I can over the next few days. With the hope I can print a few parts to fix the rest as much as the cheap hardware will allow. Been having heatbed problems the whole time too. So re-wiring that while its pulled apart. Hoping verry much the mystery will be solved.
At some point I have to just call this one a fail and make a better printer though. If I fix everything that's wrong with this one, The only original parts left will be the Arduino, 5 motors and a heatbed.
I'm not pulling anyones leg. Feel free to have a laugh though. I know I will be once its all sorted. Already am a little
DI must say though. I am amazed I got this far with the crappy parts. I think the total spend on this printer is around $270 AU. With enough left over rods etc for 2 more.
Its in the top 5 most amazing projects I have got working for next to nothing. Only reason its not top of the list is I did buy parts. Usually I don't. Have a look at my youtube... There is another printer half made with all recycled parts from hard rubbish collection. I have a spaceship engine I made from a tin can and a paperclip. Tesla Coils would on toilet paper rolls. Battery’s made from pencils, paper towel and foil.. Its just how I am. No money to spare but love building stuff.
If you can't fix it with tape and tie wire. Its broken. You need a new one.
[www.youtube.com]
[plus.google.com]
Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
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Re: Speed vs Tempreture and a tale of frustration. September 14, 2016 01:55AM |
Yeah but for $199 you could clear out all the junk from the corner of your room and have a tiny minimal printer sitting there...plug for someone else's printer,
you could have a better metal extruder for a few dollars more..
Surely the point of using a 1mm nozzle would be to have much higher layer heights & print quicker(even at a slow speed)?
your going to kill someone eventually
Edited 1 time(s). Last edit at 09/14/2016 01:56AM by MechaBits.
you could have a better metal extruder for a few dollars more..
Surely the point of using a 1mm nozzle would be to have much higher layer heights & print quicker(even at a slow speed)?
your going to kill someone eventually
Edited 1 time(s). Last edit at 09/14/2016 01:56AM by MechaBits.
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Re: Speed vs Tempreture and a tale of frustration. September 14, 2016 07:12PM |
Good to know about the filament squishing. That further confirms what I found after fixing the gear and a bunch of other stuff. I can't get the clamp loose enough not to strip without deforming...
So I'm assuming Hob marks and maybe a little flat is ok, but no squished out sides? Meh. Moving to duel drive asap anyway.
While printing bigger less detailed parts fast would be nice, and I did like the 1mm nozzle a lot. It was 1mm because I made it from a TIG collet and 5% silver solder and the silver solder broke my 0.4 0.45 0.5 0.55 0.6 and 0.7mm drill bits. Ended up using a 0.8mm bit. Can't measure the hole, but trial and error with slicing setting suggests 1mm, even though it air extrudes at 0.84ish.
If I had $200 I'd buy that printer. It looks very well thought out. I've always liked the single sided boom arm. Thats how I was planning the human torso sized printer. Because you can add a bigger bed and get longer print area without too much hassle. Now stop trying to distract me. I'm bad enough on my own lol.
I do have this one if I can get fuel money to go retrieve it from my partners house.. [www.cocooncreate.com.au] Got it at Aldi for $500 and am pretty impressed. No way I could make it that cheap. Dubious it can print ABS well, but its got all ally extruder. Maybe... I wonder if I can mill my 3mm filament down to 1.75? hehehe
Stop distracting me dammit!
After spending 12 hours or so sorting out as much stuff as I could. Including that broken gear and some serious improvements to the bed and wiring. There are now 0 clip leads in the circuit, and the bed wiring has half an ohm less resistance due to shorter wires, and the bed mosfet has some heatsink clamps on it because with the reduced resistance it now hits 104c when I turn the bed on, but then drops to 50-60c at PWM after less than a minute, rather than taking 3 min at 80c then staying at 80c. Going to make further changes with the RAMP's and mosfets soon. Because......
I'll just upload a photo.. easier than explaining. Lets just say the $20 Ramps boards on ebay should be avoided...
Also I think 3 ATX suply wires are required. One was getting hot.
The Positive side of the 11A connector (claimed 11A, tested a bit under that I think) is now an open circuit, so I bypassed that and the fuse (saving 0.1 ohms on the fuse which clearly wasn't working as expected plus another 0.05ohms on the board traces) and temporarily wired the bed connection direct to the ATX and added extra Neg supply directly to the solder pins under the bad connector.
Its pretty rough and I need to remove all the green connectors and just solder onto the board.
But it works for now, as long as I keep the extinguisher handy and don't leave it untended.
Once the green connectors are gone I will have room to properly heatsink the MOSFET with this blurry heatsink.
(its not the poor lighting or my hand shaking from too much coffee and too little sleep. The heatsink is actually blurry like bigfoot)
I gave it another try.
At first I could extrude wonderfully. From 300mm/m to 5mm/m. at 120-130c It was awesome. So I loaded up a print annnd....
Blocked. Poxy %$@$*$ *&%^^*&% $( mother *((*%**^*(*) bloody *^*&$#^$^%#^%U%$
Disassembled drilled out blockage from hotend reassembled. Air extruded great, clicked print, got a crappy calibration steps out (need to tweak temp, speed, flow rate etc to suit the lack of slipping gear).
and blocked again.
*^$#(@)%$
Dissembled again, drilled out etc etc
rinsed and repeated a few times with heat variations, more cursing, oily filament, anything I could think of. Broke the threaded tube that connects heatblock to hotend, fixed that badly due to lack of parts and lathe etc. So now the rod dosen't screw all the way into the hotend shaft. There is a 5-6mm long cavity halfway down... Which is not likely to improve things...
If I don't extrude for 10-20 secs or so the hotend shaft gets jammed up.
Its becoming very clear what the problem is.
Too much friction etc between extruder and nozzle combined with poor cooling of hotend shaft. Also likely the hotend shaft is drilled out too big inside now from all the blockages getting bored out. Its about 3.5mm most of the way through.
I need a better hotend.... Thats why I couldn't print slow before. And a better heat block, that’s why I was printing hot.
Also in the process of breaking and fixing (if you can call it fixing) the hotend. I tapped a new thread through the old heatblock from the last hotend. It has the thermistor in between heater and nozzle, rather than the crappy design I was using.
I am more confident than before that I was never extruding filament at 280c. It was more a problem of thermistor location in the heatblock. The thermistor was getting a lot more heat than the nozzle.
I can also confirm without doubt. That without an enclosure a fan does indeed help reduce curling of fine corners with ABS. Its a tricky thing to get the aim and airflow right though. But printing without my soda can airflow guide, and with the big fan pointed well above the heatblock. Made for lots of corner curling all the way up the steps. Which hasn't happened since I put the fan on weeks ago but was a big problem before fan. Printing any of the gears pictured a few posts above would not have been possible without the fan.
So having a look at what stuff I could get, should I manage to scrape up some cash. Because I think its time to fix my problems by throwing fistfulls of cash at them.
I won't be getting another one of these for $13
[www.ebay.com.au]
The top contenders are:
[www.ebay.com.au]
Or this one from an almost local supplier about 2 hours drive away. They are probably quicker on postage and I like the thermistor location a lot more.
[www.bilby3d.com.au]
Both are more than I can afford, but I think it needs to be done. Any suggestions on which is better quality? I'm inclined to go with the local store as they are less likely to falsely advertise and more likely to offer some support and warranty. But the E3D is what everyone here has been recommending. Provided that's what they actually send out, which are 50/50 odds. I've been burned a lot on ebay this year...
I'm also tempted to drill a 3mm hole down some galvanised steel M6 I have left over from the z screws. To replace the broken heat break barrel thingy. As well as trying to drill a 6mm hole into the top of the hotend so I can fit PTFE in there, but the outer diameter is only 7mm and its not going to be very strong if I do... Assuming I drill it without busting out the side or just ripping it to shreds if the bit bites a bit hard, which is 50/50 odds with so little meat to spare. I'm good with hand tools, but not that good. What about cutting the PTFE down the side so it will fit in a 5mm-ish hole? I think that could work, more than any other repair I can think of... It would mainly be something to do while waiting for parts and to satisfy my curiosity. Probably time better spent on the RAMPS board and other improvements. Make a decent frame for eg....
Edited 1 time(s). Last edit at 09/14/2016 07:20PM by Mongrel_Shark.
If you can't fix it with tape and tie wire. Its broken. You need a new one.
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So I'm assuming Hob marks and maybe a little flat is ok, but no squished out sides? Meh. Moving to duel drive asap anyway.
While printing bigger less detailed parts fast would be nice, and I did like the 1mm nozzle a lot. It was 1mm because I made it from a TIG collet and 5% silver solder and the silver solder broke my 0.4 0.45 0.5 0.55 0.6 and 0.7mm drill bits. Ended up using a 0.8mm bit. Can't measure the hole, but trial and error with slicing setting suggests 1mm, even though it air extrudes at 0.84ish.
If I had $200 I'd buy that printer. It looks very well thought out. I've always liked the single sided boom arm. Thats how I was planning the human torso sized printer. Because you can add a bigger bed and get longer print area without too much hassle. Now stop trying to distract me. I'm bad enough on my own lol.
I do have this one if I can get fuel money to go retrieve it from my partners house.. [www.cocooncreate.com.au] Got it at Aldi for $500 and am pretty impressed. No way I could make it that cheap. Dubious it can print ABS well, but its got all ally extruder. Maybe... I wonder if I can mill my 3mm filament down to 1.75? hehehe
Stop distracting me dammit!
After spending 12 hours or so sorting out as much stuff as I could. Including that broken gear and some serious improvements to the bed and wiring. There are now 0 clip leads in the circuit, and the bed wiring has half an ohm less resistance due to shorter wires, and the bed mosfet has some heatsink clamps on it because with the reduced resistance it now hits 104c when I turn the bed on, but then drops to 50-60c at PWM after less than a minute, rather than taking 3 min at 80c then staying at 80c. Going to make further changes with the RAMP's and mosfets soon. Because......
I'll just upload a photo.. easier than explaining. Lets just say the $20 Ramps boards on ebay should be avoided...
The Positive side of the 11A connector (claimed 11A, tested a bit under that I think) is now an open circuit, so I bypassed that and the fuse (saving 0.1 ohms on the fuse which clearly wasn't working as expected plus another 0.05ohms on the board traces) and temporarily wired the bed connection direct to the ATX and added extra Neg supply directly to the solder pins under the bad connector.
Its pretty rough and I need to remove all the green connectors and just solder onto the board.
But it works for now, as long as I keep the extinguisher handy and don't leave it untended.
Once the green connectors are gone I will have room to properly heatsink the MOSFET with this blurry heatsink.
like bigfoot)I gave it another try.
At first I could extrude wonderfully. From 300mm/m to 5mm/m. at 120-130c It was awesome. So I loaded up a print annnd....
Blocked. Poxy %$@$*$ *&%^^*&% $( mother *((*%**^*(*) bloody *^*&$#^$^%#^%U%$
Disassembled drilled out blockage from hotend reassembled. Air extruded great, clicked print, got a crappy calibration steps out (need to tweak temp, speed, flow rate etc to suit the lack of slipping gear).
and blocked again.
*^$#(@)%$
Dissembled again, drilled out etc etc
rinsed and repeated a few times with heat variations, more cursing, oily filament, anything I could think of. Broke the threaded tube that connects heatblock to hotend, fixed that badly due to lack of parts and lathe etc. So now the rod dosen't screw all the way into the hotend shaft. There is a 5-6mm long cavity halfway down... Which is not likely to improve things...
If I don't extrude for 10-20 secs or so the hotend shaft gets jammed up.
Its becoming very clear what the problem is.
Too much friction etc between extruder and nozzle combined with poor cooling of hotend shaft. Also likely the hotend shaft is drilled out too big inside now from all the blockages getting bored out. Its about 3.5mm most of the way through.
I need a better hotend.... Thats why I couldn't print slow before. And a better heat block, that’s why I was printing hot.
Also in the process of breaking and fixing (if you can call it fixing) the hotend. I tapped a new thread through the old heatblock from the last hotend. It has the thermistor in between heater and nozzle, rather than the crappy design I was using.
I am more confident than before that I was never extruding filament at 280c. It was more a problem of thermistor location in the heatblock. The thermistor was getting a lot more heat than the nozzle.
I can also confirm without doubt. That without an enclosure a fan does indeed help reduce curling of fine corners with ABS. Its a tricky thing to get the aim and airflow right though. But printing without my soda can airflow guide, and with the big fan pointed well above the heatblock. Made for lots of corner curling all the way up the steps. Which hasn't happened since I put the fan on weeks ago but was a big problem before fan. Printing any of the gears pictured a few posts above would not have been possible without the fan.
So having a look at what stuff I could get, should I manage to scrape up some cash. Because I think its time to fix my problems by throwing fistfulls of cash at them.
I won't be getting another one of these for $13
[www.ebay.com.au]
The top contenders are:
[www.ebay.com.au]
Or this one from an almost local supplier about 2 hours drive away. They are probably quicker on postage and I like the thermistor location a lot more.
[www.bilby3d.com.au]
Both are more than I can afford, but I think it needs to be done. Any suggestions on which is better quality? I'm inclined to go with the local store as they are less likely to falsely advertise and more likely to offer some support and warranty. But the E3D is what everyone here has been recommending. Provided that's what they actually send out, which are 50/50 odds. I've been burned a lot on ebay this year...
I'm also tempted to drill a 3mm hole down some galvanised steel M6 I have left over from the z screws. To replace the broken heat break barrel thingy. As well as trying to drill a 6mm hole into the top of the hotend so I can fit PTFE in there, but the outer diameter is only 7mm and its not going to be very strong if I do... Assuming I drill it without busting out the side or just ripping it to shreds if the bit bites a bit hard, which is 50/50 odds with so little meat to spare. I'm good with hand tools, but not that good. What about cutting the PTFE down the side so it will fit in a 5mm-ish hole? I think that could work, more than any other repair I can think of... It would mainly be something to do while waiting for parts and to satisfy my curiosity. Probably time better spent on the RAMPS board and other improvements. Make a decent frame for eg....
Edited 1 time(s). Last edit at 09/14/2016 07:20PM by Mongrel_Shark.
If you can't fix it with tape and tie wire. Its broken. You need a new one.
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Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
|
Re: Speed vs Tempreture and a tale of frustration. September 15, 2016 04:32AM |
After continuing to try to get that barrel to work. I eventually broke it.
So I made this from left over z axis rod. Its the firs time I have been happy we got that M6 for the Z.
Not that I an very optimistic about it working.
There is a short video on how I made it on YouTube. If it get enough views it might pay for a hotend in the next 50 years or so. lol.
Parts are soaking in acetone to make sure I don't break more stuff due to plastic deposits. Gonna go see if I have anything worth selling to get a new hotend.
Mong
If you can't fix it with tape and tie wire. Its broken. You need a new one.
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Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
So I made this from left over z axis rod. Its the firs time I have been happy we got that M6 for the Z.
Not that I an very optimistic about it working.
There is a short video on how I made it on YouTube. If it get enough views it might pay for a hotend in the next 50 years or so. lol.
Parts are soaking in acetone to make sure I don't break more stuff due to plastic deposits. Gonna go see if I have anything worth selling to get a new hotend.
Mong
If you can't fix it with tape and tie wire. Its broken. You need a new one.
[www.youtube.com]
[plus.google.com]
Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
|
Re: Speed vs Tempreture and a tale of frustration. September 17, 2016 01:17AM |
Well the idea is to lower the temp so I can print slower... Its all metal now but too much friction... I've k-probed the top end of the heatsink. Its only 50c max. Teflon (PTFE) will be fine. As long as the fan is on.
I got the handmade barrel working. Looks like a lot of my problems can be summed up as inefficiency in the drive train between extruder motor and nozzle.
Slipping gear and graby barrel etc etc. I made the new barrel 5mm longer, so there is now a bigger gap between heatsink and heatblock. So they are not fighting each other as much. I think that will help. I think there may be some other improvements to be had in that drive train too.
My tools are pretty basic. Used a 70 year old drill press (got it for free) this time, and an old 3mm bit I sharpened by hand on an oil stone. The trick is to spin the work piece not the bit and use the drill like a lathe. It was quicker than I was expecting. Lots of cutting fluid and just going slow to keep the heat down
I've done 5mm hole for NEMA shaft in 8mm rod before with a hand drill, and turned up the home made nozzle in the hand drill. Video of both jobs on YouTube...
6mm rod with 3mm tunnel [www.youtube.com] Although it took a little polishing to get the filament in there. The "3mm" labelled bit was actually 2.48mm, which gave me a 2.78 hole (I hate it when they do that). So rolled up some 800 grit wet & dry into a stick and honed it a bit to closer to 3mm as well as polishing the bore for less friction. Used a little valve grinding paste on a bamboo rod in the cordless drill for the last bit.
8mm rod with 5mm end bore for motor attachment. Using a cordless drill. Got about 20 microns clearance for these so they are a tight fit. [www.youtube.com]
Switched back to the blue filament because it was one less variable. Doing the calibration steps now. Turning down temp and speed as it goes. Got it down to 230c at 50% of what was close to the slowest I could print before and its looking better the lower/slower I get. A lot of what DD thought looked like z wobble in other prints is getting less and less with lower temps. So it was probably ooze of some kind making the slightly wider layers.
Not seeing much improvement from lower speeds, lower temp seems to be making the most difference. But need to test one thing at a time before I'm sure. I'd be surprised if slower wasn't noticeably neater. So far I can't tell the difference between 40mm/s and 80mm/s. Which is a bit disturbing given the nature of the machine.
Probably cant get much cooler without the enclosure. Last time I did it was splitting and warping bad. None of that this print though, not yet anyway.
Heat tower next, then try some other colours again.
If you can't fix it with tape and tie wire. Its broken. You need a new one.
[www.youtube.com]
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Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
I got the handmade barrel working. Looks like a lot of my problems can be summed up as inefficiency in the drive train between extruder motor and nozzle.
Slipping gear and graby barrel etc etc. I made the new barrel 5mm longer, so there is now a bigger gap between heatsink and heatblock. So they are not fighting each other as much. I think that will help. I think there may be some other improvements to be had in that drive train too.
My tools are pretty basic. Used a 70 year old drill press (got it for free
) this time, and an old 3mm bit I sharpened by hand on an oil stone. The trick is to spin the work piece not the bit and use the drill like a lathe. It was quicker than I was expecting. Lots of cutting fluid and just going slow to keep the heat downI've done 5mm hole for NEMA shaft in 8mm rod before with a hand drill, and turned up the home made nozzle in the hand drill. Video of both jobs on YouTube...
6mm rod with 3mm tunnel [www.youtube.com] Although it took a little polishing to get the filament in there. The "3mm" labelled bit was actually 2.48mm, which gave me a 2.78 hole (I hate it when they do that). So rolled up some 800 grit wet & dry into a stick and honed it a bit to closer to 3mm as well as polishing the bore for less friction. Used a little valve grinding paste on a bamboo rod in the cordless drill for the last bit.
8mm rod with 5mm end bore for motor attachment. Using a cordless drill. Got about 20 microns clearance for these so they are a tight fit. [www.youtube.com]
Switched back to the blue filament because it was one less variable. Doing the calibration steps now. Turning down temp and speed as it goes. Got it down to 230c at 50% of what was close to the slowest I could print before and its looking better the lower/slower I get. A lot of what DD thought looked like z wobble in other prints is getting less and less with lower temps. So it was probably ooze of some kind making the slightly wider layers.
Not seeing much improvement from lower speeds, lower temp seems to be making the most difference. But need to test one thing at a time before I'm sure. I'd be surprised if slower wasn't noticeably neater. So far I can't tell the difference between 40mm/s and 80mm/s. Which is a bit disturbing given the nature of the machine.
Probably cant get much cooler without the enclosure. Last time I did it was splitting and warping bad. None of that this print though, not yet anyway.
Heat tower next, then try some other colours again.
If you can't fix it with tape and tie wire. Its broken. You need a new one.
[www.youtube.com]
[plus.google.com]
Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
|
Re: Speed vs Tempreture and a tale of frustration. September 17, 2016 03:43AM |
Throat rods cheap M6 we got a 6m length of for $30. Either zinc or gal. Being threaded I wouldn't call it mild, Its had some hardening, but noting like stainless hardness.
The bearings are also cheap... The cheapest ebay has to offer. I spray them all down with sheep oil daily though
[www.supercheapauto.com.au]
Good thought about the sticktion though. Something to keep an eye out for.
I'm pretty happy with this for the top 3 steps
Its also clear I need to look for movement/play on the y axis. Could be the Y belt, Need to check that first as its in the list of stuff that needs attention. but I think its the x axis/boom flexing.
A lot less protruding layers on the x than y anyhow.
If you can't fix it with tape and tie wire. Its broken. You need a new one.
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Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
The bearings are also cheap... The cheapest ebay has to offer. I spray them all down with sheep oil daily though
[www.supercheapauto.com.au]
Good thought about the sticktion though. Something to keep an eye out for.
I'm pretty happy with this for the top 3 steps
Its also clear I need to look for movement/play on the y axis. Could be the Y belt, Need to check that first as its in the list of stuff that needs attention. but I think its the x axis/boom flexing.
A lot less protruding layers on the x than y anyhow.
If you can't fix it with tape and tie wire. Its broken. You need a new one.
[www.youtube.com]
[plus.google.com]
Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
|
Re: Speed vs Tempreture and a tale of frustration. September 17, 2016 03:48AM |
So I tried a heat tower. I call it the heat tower of Babylon.
I stopped it because the bottom broke lol.
I g coded it to 5c below the markings.
Actual temp for the first layer was 180ish
Then 170ish
Then 164ish
Then 257ish
I'll gcode the next one starting at 245 and drop it 4c per layer.
If you can't fix it with tape and tie wire. Its broken. You need a new one.
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Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
I stopped it because the bottom broke lol.
I g coded it to 5c below the markings.
Actual temp for the first layer was 180ish
Then 170ish
Then 164ish
Then 257ish
I'll gcode the next one starting at 245 and drop it 4c per layer.
If you can't fix it with tape and tie wire. Its broken. You need a new one.
[www.youtube.com]
[plus.google.com]
Moderators and RepRap Wiki editors have my full and unconditional permission to use any original photo's I upload for the wiki or any other way they may be of benefit to others.
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