Noob, yet to print anything with my Prusa i3 Help needed

Morning All,

I am very new to the amazing world of 3D printing, I have been lurking around these boards for quite a while leeching information.

For Christmas I was lucky enough to receive my first Prusa i3 kit (Which I picked and an now regretting). I went with this kit due to its flexibility and open nature and the fact that so many parts/upgrades can be acquired easily.

The build was fine, First lesson learnt was that an acrylic frame wasn't a good choice, so will be swapping to a ply/mdf in the near future, but its all holding together fine.

Firmware choice was repetier 0.83 along with the host and I am using slic3r to convert the models.

I have a roll of 1.75mm PLA and 1.75mm ABS and have tried printing both, but am having no luck, I have collaborated everything following guides and prints have improved in regards to the first 2 layers, but 3/4 layer on and I am getting prints like attached.

I hot-end is a paper width away from the printed, temps I have tired for PLA (Which I am using) 190-220 with the bed around 40-60.

I have found my best results with a wipe down of action and then a decent spray of hairspray.

One issue I think I do have, is that when messing with laying down the first layer, I have some how managed to block my hotend, which is causing a lack of flow/ extruder motor to jump. But due to in-experience, I may be wrong.

Any help would be appreciated,

Edited 3 time(s). Last edit at 01/07/2015 07:38AM by slim2k.

Looks like your first layer is WAY too high.

Did you calibrate the travel distance of you z axis? If you move it 1mm does it actually go for 1mm?

As I said, first layer is a lot better now, I will post an image, but the remaining layers are the problem, all detail is lost and I cannot achieve a basic collaboration cube.



No, I have not measured Z axis travel, I will check its consistent, any tips on doing it efficiently.

Edited 1 time(s). Last edit at 01/07/2015 09:20AM by slim2k.

Using a host software like pronterface you can jog your z-axis bij 10mm. If you do this you can measure with a caliper how far you have actually travelled. For good precision do a travel of 100mm. You will have to adjust your firmware steps/mm to compensate for the difference found.

Right, I just measured with calipers and a 100mm command travelled 74.95mm.

Would this be the issue?

Another issue is the extruder motor is clicking and jumping,

Edited 1 time(s). Last edit at 01/07/2015 01:20PM by slim2k.

Quote
slim2k
Right, I just measured with calipers and a 100mm command travelled 74.95mm.

Would this be the issue?

Another issue is the extruder motor is clicking and jumping,

Yes, that would be an issue.

How did you calibrate the printer? Specifically how did you determine the steps/mm to set in the firmware? The steps are what the machine uses to know how far to travel. If you issue a command to move X distance and it doesn't move that much it means your steps may not be set correctly.

The extruder clicking and jumping could be a motor current issue. You didn't say what electronics you have but if you have stepper drivers with trimpots (like Pololu style with RAMPS) try increasing the current to the motor. There is a detailed explanation on how to measure and set the current but most of us use the train and error method by turning the pot up a bit at a time until the issue is fixed.

Make sure you have heatsinks on the drivers if you are going to increase the current and if that is not enough also add a fan to your electronics. I have also used the trial and error approach and had to turn the trimpot 1/8 clockwise. You should also check that your motors don't get too hot, mine still only get lukewarm, but most motors can handle up to about 100C. I have also increased the current to the Z motors, since two motors share one driver it is needed to be able to increase your Z speed, if you feel the need for that. Mine handled 2mm/s just fine with standard settings, now I am running at 3mm/s with m5 threaded rod.

I followed the guild on the RepRap wiki for collaboration.

The kit that was bought for me has RAMPS 1.4 and sumkey stepper motors. Documentation is lacking with the printer, so I am not sure if I can change the current, but will check and upload a photo if I need too.

I really appreciate your help guys.

Most likely you have a A4988 chipset (you can check this on the chip)
Here is the page on the wiki how to adjust the current Pololu stepper driver calibration

Here is some more information from the forum

I will check when I get home from work and upload a photo of my mega.

I am a Software developers by trade and enjoy hacking around, but this 3d printing takes it to the next level.

Hot end is currently in a acetone bath, as following a guide on youTube, the flow was curling slightly.

I am going to read up on the stepper calculations for the Z axis motors. The repetier calculations are dependent on other variables if I remember correctly, which made me cautious about making any changes.

What are your guys views on repetier, I noticed that many use Marlin, is that better or just choice? I went with repetier as it was supplied on the disk with my printer.

Cheers

Jon

Evening,

Sorry for the delay in replying work has been taking over.

I cleaned/unblocked my hot end. Upgraded the firmware to 0.92 and thought that I had sorted my extruder stepper issue.

My first few points were good from layer 1-4 and infill perfect as you can see. But then it all goes wrong and now my hot end is blocked again (curling pla as its extruded)

Do all people have these issues, I've attached photos and a video.

I don't see your photos (except in the first post) so I can't identify your hot end, but it sounds like you are saturating the throat with heat, causing the filament to jam inside. I had this problem until I made some changes to keep my heat cool. I insulated the hot end, added a couple washers and made sure that the heat sink was in good contact with the throat and well cooled. I haven't had to take the hot end apart once since then!

There are photos of my hot end in the links below...

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-David

Find me online at:
Thingiverse
Instructables.com
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Check out my FolgerTech Prusa i3 (plexi) at MindRealm.net

Hi Guys,

Sorry for the Huge delay and lack of photos uploaded. I am still no closer. But have only really had time to research setting up my Z stepper in the firmware.

I think from the reading I have done I have 3 issues.

I am over/under extruding, my Z step per mm in the firmware isn't correct. its set to 80 (repetier), my nozel keeps getting blocked. (Filiment curling as it exits the hole)

Finally, not sure if its linked. But what should the feed rates be in Slic3r config as I am not sure if this is correct,

Is the fact, I bought a fairly cheap chines printer the greater issue here, or is this part of the process of open source 3d printing?

Please find photos attached.

This is the actual printer I bought - Prusa i3

Edited 2 time(s). Last edit at 02/02/2015 08:32AM by slim2k.

As I read in the forums, there are some having big problems, which can mostly be solved with proper configuration and calibration. It's just not easy to know, what to
look for.
I would say, that your feedrate isn't correct. I'm not sure if it's too low or too high, but I would think too high.
Could you post your "configuuration.h"?
Just to compare, my steps are:

#define DEFAULT_AXIS_STEPS_PER_UNIT   {80,80,4000,473}  
#define DEFAULT_MAX_FEEDRATE          {500, 500, 1, 25}

(using 1/16 steps, with the 3 jumpers under each stepper-driver set/connected)

Your Z-Rods are standard M5 rods, aren't they?

Edited 2 time(s). Last edit at 02/02/2015 01:28PM by Ano.

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Prusa i3 Rework (from Replikeo.com) & original Prusa i3 MK2 (from shop.prusa3d.com) << the MK2 definitely is worth the higher cost!
Print Troubleshooting Guide // Visual troubleshooting guide

Here is the config.h file from repetier that I have uploaded to the board.

I am not sure about the jumpers, but will confirm tonight when I get home from work.

I am unsure what M* my Z rods are, how can I check.

Edited 1 time(s). Last edit at 02/03/2015 06:40AM by slim2k.

Quote
slim2k
[...]
I am unsure what M* my Z rods are, how can I check.

I'll look into the config this evening.
To meassure the rods, just measure the diameter. A caliper would be best, but any other tool also works.
Should be 5mm (there aren't any 4,75mm [there are but not used in these cases], so if it's about 5, it's right).

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Prusa i3 Rework (from Replikeo.com) & original Prusa i3 MK2 (from shop.prusa3d.com) << the MK2 definitely is worth the higher cost!
Print Troubleshooting Guide // Visual troubleshooting guide

Cheers, measure with calipers tonight and report back along with stepper driver jumper settings.

FYI, the firmware is the standard download from the site, from other research. I think my Z axis is totally out as all 3 axis are set to 80 steps per mm and from my reading last night and this morning. This is correct for belt/pully steppers. But should be around the 2560 from what the calculator is telling me, which is obviously a huge difference to the 80 set for the Z axis in the config file.

I have attached a photo of my board, it isnt a full ramps set up from what I can see. I have checked the suppliers site and its this Board excuse the wiring mess. I am still fiddling at the moment as you know.

EDIT:: I have found the board on here [reprap.org] and more details about it here I think I am OK because the article states - "MKS BASE is a feature rich all-in-one electronics solution for Reprap and other CNC devices.
It features an onboard ATmega2560. Its five motor outputs are powered by A4982 stepper drivers.
The board can use the same firmware as Ramps1.4."

How dose this affect things, Massive lesson learnt not to buy cheap from China!! Have I wasted money?

Edited 4 time(s). Last edit at 02/03/2015 09:04AM by slim2k.

Hi,

As you can see no jumper settings have been set on the board and the diameter of the rods is 8mm.

Ok, so I think you should aim for calibration of your motors then first.
- Command (by software) to raise the Z-axis by 100mm and measure how much it really moves. As you said above, it only moves 74.95mm, so adjust your "steps_per_unit" to: "current_value*(100/74,95)"
Don't write the formula, just write in the value ^^
- Do the same thing for x- and y-axis
- Then do the same for the extruder. Unplug your hotend (to not waste filament), then mark the filament with a pen and command 100mm of extrusion. Measure the real extruded filament and adjust the value. Then do it again and
look, if it now extrudes 100mm

It's these lines you will have to change:

#define XAXIS_STEPS_PER_MM 80
#define YAXIS_STEPS_PER_MM 80
#define ZAXIS_STEPS_PER_MM 80    <--- for example: 80*100/74,95 = 107

#define EXT0_STEPS_PER_MM 370

And btw: no, the Chinese board is no problem, it's in fact a RAMPS+Arduino on one board. And a lot of RAMPS are coming from China, too. Some make trouble, but by far not all.

Oh, and for the rods, I meant the threaded rods not the straight ones. Or are the threaded one 8mm? Anyhow, try the above ^^

Edited 6 time(s). Last edit at 02/03/2015 04:15PM by Ano.

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Prusa i3 Rework (from Replikeo.com) & original Prusa i3 MK2 (from shop.prusa3d.com) << the MK2 definitely is worth the higher cost!
Print Troubleshooting Guide // Visual troubleshooting guide

Thank you very much for the detailed reply. I will cook the wife dinner, to try and get some time on my "Toy"

I am glad to hear, that the board is suffice for now. I am happy to spend money on getting some basic prints out. But don't really want to invest any great sums at the moment.

Yes, the 8mm (78.9mm actually) was for the 2 threaded rods that drive the Z axis movement.

I have removed the hot end and its currently in a bath of the wife's acetone to clean it up.

I will report back with my findings.

one issue I do have, is that the NON-threaded rods slide. there are nut's and bolts that a act as a clamp against the acrylic. but you have to be so careful tightening them up, otherwise the acrylic breaks. There, were a number of "O" rings supplied. but clearly redundant as there is no groove for them to fit into.

I'm sorry, but I have no solution for the last problem, as I own a aluminium-singleframe kit. I think it should be sufficient to tight them just enough to hold it. You don't need to apply enough force to break the acrylic.
Perhaps a bit of tape around those holes could help, as it should perhaps prevent breaking, at least a bit.

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Prusa i3 Rework (from Replikeo.com) & original Prusa i3 MK2 (from shop.prusa3d.com) << the MK2 definitely is worth the higher cost!
Print Troubleshooting Guide // Visual troubleshooting guide

I do plan on swapping the frame out to either a wooden like this - eBay Link or an Aluminum frame

Morning,

Huge progress last night, managed to get 3 hours on the printer and re-calibrated the whole thing. Has to revert back to repiter firmware 0.83 as I couldn't get my extruder to work with 0.91 or 0.92.

My steps per mm are 133 for X & Y and 780 for Z extrusion is 300. (I calculated this by moving/extruding 10mm and measuring with calipers) as soon as the changes were made, the printer now is much slower at moving in all directions, is the correct?

Prints are still not there, but I think this is due to my hotend as the filament is curling when it comes out of the hole instead of a straight down flow. Its currently in a bath of acetone and I am looking to swap it out for a J-head. but the wiring is putting me off at the moment.

I have attached photos (excuse quality) of the 0.5mm thin wall calibration cube and the first layers were great. but you will see the belt jumped twice, which caused the layers after to mess up. I tightened the belt up and this is now not an issue.

My main issues on following prints seemed to be lack of flow as if the filament was getting backed up in the hotend. All cooling is on and when it prints, the layers are really good.

The other issue that come apparent, was that the base of items would curl, I tried heating the bed to 50 and then taking it up to 60. I am using PLA and printing at 210.

Thanks for all your help so far, I finally feel like I am making progress.

I am not having any experiance with pla, but you could try to print a very thin first layer. It helps me with getting ABS to stick on the bed.
Set the first layer height to 0,12mm in slic3er.
For the speed: You could adjust the speed in slic3r, if you want to print faster. But to start with, speed should not be a real issue. Get it printing
good enough and then you can think about that =)

What do you mean by curling? If I try to extrude filament without it being on the bed (so in mid air), my filament is not falling straight down at all.
But that's no issue, cause it will not happen while printing. Either there is a heatbed right underneath or the filament is printed in air for bridging,
but then the extruder moves while extruding, which leads to a bridge effect.

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Prusa i3 Rework (from Replikeo.com) & original Prusa i3 MK2 (from shop.prusa3d.com) << the MK2 definitely is worth the higher cost!
Print Troubleshooting Guide // Visual troubleshooting guide

your print looks like it is shifting in the x or y axis, check your belt tension, it should be taught so that you can make it twang like a guitar string, not like a slingshot or bow. if the belt does not have enough tension then it can cause backlash or slipping on the pulley.

the calibration of your x and y axis will need to be done again once oyu tighten your belts