Problem with complex prints...

I've been trying to print some more complex items today and I seem to be having problems I can't figure out and I'm uncertain what the cause(s) might be.

The 1st layer seems to be spot on as you can see by this single layer print I did, I would consider this a successful print.




Then I tried something more complex and again the first layer looks good but then its utter failure. Anyone have ideas on what I should start looking into for a fix? The model suggested printing at .1 layer thickness but my machine wouldn't even lay material down at that thickness so I ran it at .3. I'm running a coreXY with an E3D hot end .4mm nozzle.









I just let the print finish even though early on I could tell it was going to be total trash...

Thanks for any input.

ampapa,

Edited 2 time(s). Last edit at 12/30/2017 04:22PM by ampapa.

2 more of the lifted print...

I think you have a zero where it shouldnt be, .01 or .03 are too low, .1 is really fine, start out at .28 and work your way down when needed.(though this depends on your Z screw & nozzle size)

Edited 1 time(s). Last edit at 12/30/2017 03:47PM by MechaBits.

Thanks, you're correct.. edited.

How Fast are you trying to go? Material? Part Cooling?

Even with PLA, I always use a brim on blue tape. That keeps the corners down.
I just started to use BuildTak on a cold bed. WOW, what a difference...

Thanks for the input .

I'll try adding a brim for sure.

I'm printing PLA and here are the settings in Slic3r.



Can over/under extrusion also be a part of the problem I have a 1 in the extrusion multiplier?

ampapa,

I'd take first layer down to 20mm/s and max speed 40mm s(maybe constant speed all over & use speed multiplier) till you get something good and go from there.
and that colour looks sick maybe filament is bad too? what make? & temp

Edited 1 time(s). Last edit at 12/31/2017 12:03PM by MechaBits.

Thanks I'll give those settings a shot and see what happens.

The material is form Hatchbox - PLA... recently opened.

1st layer is printed at 205 and other 195.

ampapa,

I don't know, if this is still an issue, but Slic3r had a bug in the gap-fill. Those traces were massively overextruded.
That's why I set gap fill speed to "0" to disable it completely.

o_lamp, what part of the model is the trace so I can identify what over extrusion looks like?

Quote
o_lamp
That's why I set gap fill speed to "0" to disable it completely.

I'll also try to turn this setting off.

Should I be using Cura or another slicer program possibly Slic3r is not best suited for us beginners?

ampapa,

Edited 2 time(s). Last edit at 01/01/2018 07:48AM by ampapa.

Matter Control for Ease of use.

I've been working on trying to get a better print and I think I've come across the actual problem, over extrusion. I was using the stacked Cube as suggested by Triffids guide and then adjusting as the print was going in the DuetWifi interface.

This picture is with the following in my config.g file (M92 X100 Y100 Z1600 E145.52) I think this picture is definitely over extruding, am I correct?


The second picture is with an 15% reduction (M92 X100 Y100 Z1600 E116.416)


I may have gone a little too far on the E-steps, but that leads me to question how accurate my initial settings/calculations were... The difference between my original setting and the adjusted 15% settings seems to indicate I calculated the E steps incorrectly.

My machine uses a Bowden extruder and a DuetWifi without any big/small gear on the extruder and only a hobbed gear, pretty standard stuff here.

Quote
Triffids Guide
e_steps_per_mm = (motor_steps_per_rev * driver_microstep) / (hob_effective_diameter * pi)

I come up with e_steps_per_mm = (200*16) / (7.19*3.14159) = 3,200/22.5880321 = 141.66 which puts me in the ballpark of my original calculation and then running 100mm of filament and calcualting the difference is where I had my original setting.

So, does the hob_effective_diameter mean the measurement at the smallest part of the hobbed gear? I assume yes.

What am I missing here..

ampapa,

Edited 1 time(s). Last edit at 01/02/2018 11:53AM by ampapa.

The effective hob diameter is hard to measure because the teeth bite in to the filament by an unknown amount. Rather than calculate the extruder steps/mm, it is better to measure it. Even after measuring it, you may need to make an adjustment to the extrusion factor of up to about 5% to get the best results from a particular filament. You can make this adjustment in the web interface or on PanelDue while the print is running.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Thanks dc42. I'll make a better attempt at adjusting the extruder.

Am I correct in the assumption of over extrusion above?

ampapa,

Yes, your first photo before the 15% reduction shows over extrusion.

Edited 1 time(s). Last edit at 01/02/2018 06:49PM by dc42.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Thanks for confirming.

A follow up question... assuming that my steps were correct on my extruder as originally calculated

Quote
ampapa
e_steps_per_mm = (200*16) / (7.19*3.14159) = 3,200/22.5880321 = 141.66

What would control over extrusion in Slic3r, the extrusion multiplier, other settings?

The extrusion multiplier seems to be required...


ampapa,

The filament diameter and extrusion multiplier in the slicer control it. But I find it easier to adjust the extrusion multiplier on the printer instead, it means I don't have to re-slice when I want to change it.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I feel like I'm getting real close but still missing something obvious.

This print last night gave me problems either at the layers below/above the letters or vice versa, possibly dues to speed or jerk or???



ampapa,

I'm sure the nozzle bumped into something and caused skipped steps. You often see corners of a print raising, especially when you print too hot or have z-lift during retraction. It takes a while to dial that in, and you have to do it again with a new spool...

I recently did that with a new Bowden hotend. I used the epic troll ( or was it the ultimate troll? ) from thingiverse. Anyway, it is still not perfect. I have to improve my part cooling too.

Those look good...

It seems like I actually hear something when it gets to the corner but I'm still new to the game.

Here is a video clip I took, right around the 8 and 10 second mark you can hear a click I think.
Print click

What I find so odd is that the only place it creates a problem is when it prints the height of the letters.. why at only those layers?

I realize diagnosing over a forum is pretty difficult but I'm so close I can taste it..

ampapa,

Edited 1 time(s). Last edit at 01/05/2018 04:14PM by ampapa.

Everytime the nozzle of a Delta moves across a gap in the part, like at the start/end of the letters in the cube, your print is in danger.
When you have some play in the mechanic parts, the nozzle will drop a bit and bumps in the part. Sometimes it's so bad, it kicks the part from the printbed, sometimes it skips steps or just makes some scratching noise and moves on.
When your xyz-steppers are on, can you rotate the effector by hand? Do you feel any wiggle or hear the rod ends rattle? That's a bad sign.

I've just made my first prints with magnetic rods ( from Haydn Huntley ). It's a big difference compared to Traxxas rod ends.

Cube looks good in video, but maybe the lines in the stills are from belt & pulleys, any slack or movement?

This is being printed on a CoreXY machine... so I can't compare.

Thanks,

Quote
ampapa
I feel like I'm getting real close but still missing something obvious.

This print last night gave me problems either at the layers below/above the letters or vice versa, possibly dues to speed or jerk or???
[attachment 101181 IMG_2161.JPG]
[attachment 101182 IMG_2162.JPG]

ampapa,

Check your belt tension. Thats likely backlash as its showing up after a direction change.
Core X/Y have long belts so tension is a big issue with them.
You may find you need higher quality belts.

Edited 1 time(s). Last edit at 01/06/2018 10:35AM by JustSumGuy.

As I continue to print more objects I'm finding that a lot of the issues I'm dealing with are related to stringing and surfaces not being flat to build upon.

It seems as though the nozzle is dragging across the print causing bumps and ridges, leaving the layer not flat to print the next layer.


Is that a function of the printer or the printing of the filament?

Edited 1 time(s). Last edit at 01/07/2018 07:15AM by ampapa.

The problems I see in that picture is at the turningpoints. The printhead seems to tilt or the belts have backlash. Your printer has v-slot wheels? Maybe check them again for any wiggle.

IMHO.
I suspect this is a shrinkage issue.
What temperature are you using. The stringing on the earlier parts is also temperature related. I don't use PLA but always try to use the lowest temperature I can.
For the issue on the cube:- What infill are you using and is the cube "solid" or has a void inside.
We do see this afect where there are horizontal holes through a part and it seems related to those parts being printed with several "islands". You don't have that on this cube but i wonder if the internal structure is still contributing to the issue.

Temps are 195 first layer and 183 for the remaining layers.

The cube was printed with a 25% infill.

Ampapa,

I've been making some progress when printing items but I'm still noticing that I am getting artifacts when the print head moves, some straight lines and then some blobs.


What controls these types of items in the software is it mostly controlled by lift Z, length of retraction,retract on layer change, etc.?

I'm printing with:
PLA
185
Bowden Extruder
Slic3r

ampapa,