Migbot Prusa i3 Unofficial Support Thread

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gotswrv
Does anyone know where to get a quality heating element for the extruder? Ohh, I'm in the US.

Having a lot of issues getting it tuned in. Autotune returns wildly different values from day to day. When everything looks good I cannot make it through a print without a thermal fault. Seems like spending a few extra dollars on the element might be worth the hassle saved.

[reprapchampion.com]

@Wes78, Thanks for that!
but that place is dangerous... Ended up deciding to swap out everything to 24v.

Quote
Taisiya
hello,

Yes, I saw this depository, but shouldn't there be an images instructions?

Did you receive a separate instructions sent with the Kit?

May I ask if you could email me photos/ scans of you instructions and wiring pics please?

my email is mag8891@gmail.com

many thanks.

pics here
[github.com]

one of the links in the email I got after the fact
[www.instructables.com]

real prusa
[manual.prusa3d.com]

My folder of pics that I found is about 1GB zipped, so I'm not really sure how to share that with you.
Guess I could reduce the file sizes and put it in dropbox or something. Let me know if teh above links are not enough.

Hi guys,

I'm new here, I didn't find anything via search so better ask. I have a Migbot i3 printer setup (acrylic type frame) that I'm very very pleased with. The only problem that I have with it is that it's a bit decalibrated as default. I've calculated that the propper settings for steps/mm must be:
X: 80.16 (80 default)
Y: 80.24 (80 default)
Z: 399.0 (398.2 default)

Actually, after working the numbers out, this is not a problem. The fact that it resets to defaults every time I take the power out is what bugs me. Any way I can modify the current firmware on it(download it somehow, maybe connect it to the PC?) then reupload it only with the motor steps/mm changed?

Thanks in advance,
B

Edited 1 time(s). Last edit at 02/26/2016 12:58AM by Boggy22.

Boggy, you don't want to be changing those steps really. Keep them as default and use the Extrusion multiplier in your Slicer. By changing the steps you're amplifying any inaccuracies on large prints. What may be 0.1 or 0.2mm could end up being 2mm on a large print.

The base firmware is Crap from the base github repo, grab my 1.1 version from here and upload it, there are several people here that will vouch that my configs work a hell of a lot better.

Thank you, I might give it a try. Which one should I upload? I have the 220x220x180 bed, no auto-leveling. Is that the large bed?

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Boggy22
Thank you, I might give it a try. Which one should I upload? I have the 220x220x180 bed, no auto-leveling. Is that the large bed?

That's the standard. The Large is 220x260.

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gotswrv
@Wes78, Thanks for that!
but that place is dangerous... Ended up deciding to swap out everything to 24v.

Fill me in please, dangerous how? I haven't had a problem one with them or there stuff

Quote
Wes78

Quote
gotswrv
@Wes78, Thanks for that!
but that place is dangerous... Ended up deciding to swap out everything to 24v.

Fill me in please, dangerous how? I haven't had a problem one with them or there stuff

Think he means dangerous to his wallet..

Quote
Ax

Quote
Wes78

Quote
gotswrv
@Wes78, Thanks for that!
but that place is dangerous... Ended up deciding to swap out everything to 24v.

Fill me in please, dangerous how? I haven't had a problem one with them or there stuff

Think he means dangerous to his wallet..

Exactly!
Went there to spend $5 left $50 lighter...

Good share!

Quote
gotswrv

Quote
Ax

Quote
Wes78

Quote
gotswrv
@Wes78, Thanks for that!
but that place is dangerous... Ended up deciding to swap out everything to 24v.

Fill me in please, dangerous how? I haven't had a problem one with them or there stuff

Think he means dangerous to his wallet..

Exactly!
Went there to spend $5 left $50 lighter...

Good share!

OHH hahahaha yeah man i feel ya there !!

Hi again guys. I did find a while ago that the cause for my filament being stuck was the un-chamfered throat in the extruder. I "dremeled" a nice cone shape at the top where the filament comes in and it went smoothly afterwards. After having a clogged nozzle I decided to dip the hot end in acetone because the aluminum block was dirty too. Stupid thing, because I think the teflon lining inside the throat was damaged in the process. Even after changing the nozzle, I have problems with filament feeding through. I want to order new ones, but I don't know exactly what the length is(I don't want to unscrew it again before a replacement because I'm going to screw up the thread in the aluminum block).

Do you have any idea if they're M6x26 or M6x30mm? These are the main sizes I found on the internet.

Also, some people are NOT using teflon liners inside for ABS printing... They do polish the inside of the throat properly, but I'm having doubts about doing this myself. Any tips for smoother feeding?

Thanks!

Edited 1 time(s). Last edit at 02/29/2016 12:48PM by Boggy22.

Quote
Boggy22
Hi again guys. I did find a while ago that the cause for my filament being stuck was the un-chamfered throat in the extruder. I "dremeled" a nice cone shape at the top where the filament comes in and it went smoothly afterwards. After having a clogged nozzle I decided to dip the hot end in acetone because the aluminum block was dirty too. Stupid thing, because I think the teflon lining inside the throat was damaged in the process. Even after changing the nozzle, I have problems with filament feeding through. I want to order new ones, but I don't know exactly what the length is(I don't want to unscrew it again before a replacement because I'm going to screw up the thread in the aluminum block).

Do you have any idea if they're M6x26 or M6x30mm? These are the main sizes I found on the internet.

Also, some people are NOT using teflon liners inside for ABS printing... They do polish the inside of the throat properly, but I'm having doubts about doing this myself. Any tips for smoother feeding?

Thanks!

Length doesn't matter, you're better off picking up a lined one over a all metal mainly due to the MK8 being prone to heat creep so you're gonna have more blockages. Tbh, you're better off swapping the whole thing out for a E3D Lite6 or E3D v6. You'll find the print quality improves drastically. There's mounts you can print on Thingiverse, like mine.

Edited 1 time(s). Last edit at 02/29/2016 01:11PM by Ax.

I second AX,

the V6 lite is like 38 bucks dont get a knock-off for 20$ get the real deal
I have gotten the lite and the full V6 here and LOVE them

If you get a lined one or the V6lite just dont go over 240-245cMAX as that will damage the liner

Fast shipping.
[www.filastruder.com]

Edited 1 time(s). Last edit at 02/29/2016 01:33PM by Wes78.

Do you guy keep the feeder on the X carriage or remote feed with the v6?

Also wanting to know if a G10 frame is really an upgrade?
Tired of the frame coming loose and loosing shape.

Quote
gotswrv
Do you guy keep the feeder on the X carriage or remote feed with the v6?

Also wanting to know if a G10 frame is really an upgrade?
Tired of the frame coming loose and loosing shape.

Well I know you've seen what I do with mine as you've collected it. If the G10 frame is metal, it's a definite upgrade..

So, I tested my top mounting E3D mount last night. Works well, but once again Ax derps, it was meant to work with the stock sensor mount, but that's actually too long (!). So I've modified the stock sensor again to allow for a lot of travel. With this E3D mount you can actually get the full 180 Z travel, in fact you gain another 5-7 mm. No more bastard snapping of Sensor mounts for me. This one is going on the other 3. Oh, yeah, I now have a 4th Migbot..

[www.dropbox.com]

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gotswrv
[www.dropbox.com]

You, sir, are awesome. Adding that to the wiki page.. as soon as I can work out what link is making it think it's spam..

Ahhhh the Fun!!!

SO been doing some upgrades.. (At work so no pics)

SO was printing in ABS.. I had gone through two spools of PLA getting some designs sorted.
Smelled burning plastic.. thought it was the ABS... No it was the connector to the heat bed on my motherboard.

A couple hours later I cleaned up and rebuilt the connectors, re-soldered it, and it was much happier.. but I decoded to stop using the factory board to power the heatbed.

Ordered a switching power supply, and one of the relays... which turned int TWO relays.. one 25 and one 100. Plus heat sinks for them both and heat sink compound.
Then ordered a new silicone heater for the heat bed. (since it sticks under the aluminum)

Then before installing all that.. ordered a set of longer 8mm rails, and a leadscrew to compliment them.. along with associated sliders etc. SO I can lengthen my y axis to appx 16" of print area. (STILL waiting for the rails to arrive from china.. I think they got lost in NY)

Go to print parts for the leadscrew conversion.. BLAMMO spaghetti. My y axis stops working and spits out its belt.
Needless to say.. I am going to have to repair the belt holder, and make it functional until I can get the leadscrew parts. But hope to have pics sooner rather than later.

Hi folks,

I'm in the midst of getting my i3 to work. It's all assembled, Ax's Marlin 1.1 firmware loaded, large size bed all setup and leveled, setup using autolevel (using Ax's large bed & auto level configuration.h). I did the auto PID tuning as well on the extruder.

Here's my problem.... if I print PLA at 205 degrees it prints fine, but if I print at 210 I get Thermal Runaway issues. Usually by around 94% of this particular print; however, I just got one at 28% through the print.

I have not touched the thermal runaway settings in the firmware/config.

I have checked the thermistor's set screw (backed it off and then gently snugged it up).
After that I measured the resistance of the bed thermistor and hot end's thermistor and they were identical.

I've searched through this awesome thread and found most of the answers to all the other hurdles I've hit up to this point. But I'm stumped on this one - maybe I missed it in this thread, but if someone could point me in the right direction I could stop beating my head against the wall. ;-)

Here's my setup:
- this printer with the MK8 Pro extruder + large bed + auto leveling platform
https://www.3dprintersonlinestore.com/electron-3d-prusa-i3-kit
- configuration.h file attached
- printing PLA (eSun and the stock white that came with the printer)
- stock aluminum bed with tape and glue (for now, have glass, etc. planned for later)
- printing temps of 205 and 210 with bed at 50
- layer fan to 50% after first layer (I believe- just defaulted) and 80% at max (tried dropping this from default of 100% in case it was cooling the hot end)
- using Repetier Host to generate gcode then printing via SDCard (actually printing via USB does the same thing)
- firmware: Ax's Marlin 1.1 using the large bed, auto level configuration.h (adjusted for auto PID tune, etc.)

Thanks in advance for any / all assistance.
Jason.

Quote
uberjay
Hi folks,

I'm in the midst of getting my i3 to work. It's all assembled, Ax's Marlin 1.1 firmware loaded, large size bed all setup and leveled, setup using autolevel (using Ax's large bed & auto level configuration.h). I did the auto PID tuning as well on the extruder.

Here's my problem.... if I print PLA at 205 degrees it prints fine, but if I print at 210 I get Thermal Runaway issues. Usually by around 94% of this particular print; however, I just got one at 28% through the print.

I have not touched the thermal runaway settings in the firmware/config.

I have checked the thermistor's set screw (backed it off and then gently snugged it up).
After that I measured the resistance of the bed thermistor and hot end's thermistor and they were identical.

I've searched through this awesome thread and found most of the answers to all the other hurdles I've hit up to this point. But I'm stumped on this one - maybe I missed it in this thread, but if someone could point me in the right direction I could stop beating my head against the wall. ;-)

Here's my setup:
- this printer with the MK8 Pro extruder + large bed + auto leveling platform
https://www.3dprintersonlinestore.com/electron-3d-prusa-i3-kit
- configuration.h file attached
- printing PLA (eSun and the stock white that came with the printer)
- stock aluminum bed with tape and glue (for now, have glass, etc. planned for later)
- printing temps of 205 and 210 with bed at 50
- layer fan to 50% after first layer (I believe- just defaulted) and 80% at max (tried dropping this from default of 100% in case it was cooling the hot end)
- using Repetier Host to generate gcode then printing via SDCard (actually printing via USB does the same thing)
- firmware: Ax's Marlin 1.1 using the large bed, auto level configuration.h (adjusted for auto PID tune, etc.)

Thanks in advance for any / all assistance.
Jason.

Ok, quick question, is it the temperature dropping or increasing with the runaway?

Hey Ax,

The temperature drops. On the Thermal Runaway frozen screen I typically see ~195/0 as the last hot end temp when printing 210.

Thanks,
J

Quote
uberjay
Hey Ax,

The temperature drops. On the Thermal Runaway frozen screen I typically see ~195/0 as the last hot end temp when printing 210.

Thanks,
J

Are you running the stock wire from the PSU to the MKS motherboard?

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Ax
Are you running the stock wire from the PSU to the MKS motherboard?

Yup. I think the resistance I measured (at the plug end) was ~ 125 k.

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uberjay

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Ax
Are you running the stock wire from the PSU to the MKS motherboard?

Yup. I think the resistance I measured (at the plug end) was ~ 125 k.

Change it to 14 AWG, It's under gauge. Had something similar with the 4th Migbot's bed until I changed out the wire. Made a huge difference. I'm betting the wire's warm when the printer is running.

Edited 1 time(s). Last edit at 03/08/2016 04:48PM by Ax.

Quote
spinracing
Ahhhh the Fun!!!

SO been doing some upgrades.. (At work so no pics)

SO was printing in ABS.. I had gone through two spools of PLA getting some designs sorted.
Smelled burning plastic.. thought it was the ABS... No it was the connector to the heat bed on my motherboard.

A couple hours later I cleaned up and rebuilt the connectors, re-soldered it, and it was much happier.. but I decoded to stop using the factory board to power the heatbed.

Ordered a switching power supply, and one of the relays... which turned int TWO relays.. one 25 and one 100. Plus heat sinks for them both and heat sink compound.
Then ordered a new silicone heater for the heat bed. (since it sticks under the aluminum)

Then before installing all that.. ordered a set of longer 8mm rails, and a leadscrew to compliment them.. along with associated sliders etc. SO I can lengthen my y axis to appx 16" of print area. (STILL waiting for the rails to arrive from china.. I think they got lost in NY)

Go to print parts for the leadscrew conversion.. BLAMMO spaghetti. My y axis stops working and spits out its belt.
Needless to say.. I am going to have to repair the belt holder, and make it functional until I can get the leadscrew parts. But hope to have pics sooner rather than later.

I may be in the UK, but if you want a new one printed, let me know.

Uberjay,
Change out the wires as mentioned.

Another thing I've found troublesome is if a fan is is blowing on the hot end. I now have the extruder fan taped up to keep any leakage from getting to the hot end. I couldn't feel the airflow, never would have guessed it was trouble. Ended up accidentally having that fan off once and noticed my temp was rock solid all of the sudden. No more run always ever, had to recalibrate too, so obviously it was a thing.

Can anyone share a slic3r ABS config file with me?

Quote
Ax
Change it to 14 AWG, It's under gauge. Had something similar with the 4th Migbot's bed until I changed out the wire. Made a huge difference. I'm betting the wire's warm when the printer is running.

Thanks... I'll get to that for sure. Did a quick hack to see if I could kludge out the hysteresis calc without letting it dip to low or jump too high:

#define THERMAL_PROTECTION_HYSTERESIS 20 // Degrees Celsius

(default was set to 10)

With the above and a print temp of 210 it was successful. I figure I'm still safe at this print temp - min point should e 190 and max 230 which is (I believe) in the range for PLA and given that my temp variance was a drop not spike.

Anyway.... I plan to:

a) get the larger wire (will take longer to enact for me 'cuz I'm lazy by nature )
b) will also try adjusting the extruder fan's airflow as I've read and is mentioned in another comment / reply here.

Then I just need to dial it in so my print doesn't curl without a brim. .... all in due time though.

Thanks so much for your help Ax....
J