Re: Migbot Prusa i3 Unofficial Support Thread March 08, 2016 09:44PM |
Registered: 8 years ago Posts: 23 |
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gotswrv
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.
Re: Migbot Prusa i3 Unofficial Support Thread March 09, 2016 07:30AM |
Registered: 9 years ago Posts: 269 |
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uberjay
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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
Re: Migbot Prusa i3 Unofficial Support Thread March 09, 2016 07:43AM |
Registered: 8 years ago Posts: 23 |
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Ax
Not a problem, I would change the wire out on both the bed and from the PSU ASAP, they are both under gauge, them getting warm is a fire hazard as they are resisting the flow of current. The bed can be 16 AWG as it's not pulling as much current as the board.
Re: Migbot Prusa i3 Unofficial Support Thread March 09, 2016 07:58AM |
Registered: 9 years ago Posts: 269 |
Re: Migbot Prusa i3 Unofficial Support Thread March 09, 2016 08:33AM |
Registered: 8 years ago Posts: 23 |
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Ax
No, just the power wires.. the thermistor wires do not carry much current at all. As for buying a $300 printer, the old adage apples. You get what you pay for.
Re: Migbot Prusa i3 Unofficial Support Thread March 09, 2016 10:45AM |
Registered: 9 years ago Posts: 103 |
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spinracing
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.
Re: Migbot Prusa i3 Unofficial Support Thread March 09, 2016 11:11AM |
Registered: 9 years ago Posts: 31 |
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uberjay
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Ax
No, just the power wires.. the thermistor wires do not carry much current at all. As for buying a $300 printer, the old adage apples. You get what you pay for.
Thanks... again on the wires/confirmation.
Yeah, I get the cheap printer thing. But I don't agree with vendors that sell it as a package that should work and, well, it doesn't. Also, it hits hard here as that $300 printer that I got was actually $410 after the options I got. For me that equates to over $600 Canadian Dollars. So, not exactly chump change for me anyway. But, yes, if I look at the market of 3D printers I do value the price ... just not the expectation this vendor set that what I would get would be (at least) functional.
Anyway... as I mentioned before, I am very grateful for you and your help. You are very gracious with your time helping all of us who are lost and needy ;-).
Cheers,
J
Re: Migbot Prusa i3 Unofficial Support Thread March 09, 2016 01:31PM |
Registered: 8 years ago Posts: 23 |
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Canadian Geek
Hey J, you must have some 14 AGW wire lying around for one of your RC planes. I forgot to tell you that I changed those wires on mine and a lot of problems went away. I used some silicone coated 14AGW due to the flexibility. A bit more expensive but you saw how I have the wire in the chain guide so it flexes better.
Jeff
p.s. Ax, Thanks for helping J. I was beginning to run out of ideas so I told him he should post here. Forgot about the wire. One of the first things I did months ago so forgot all about it. Yeah, the original wires used to get warm. Cheap Chinese setups. Save a buck without thought to safety.
Re: Migbot Prusa i3 Unofficial Support Thread March 09, 2016 01:49PM |
Registered: 9 years ago Posts: 11 |
Re: Migbot Prusa i3 Unofficial Support Thread March 09, 2016 01:54PM |
Registered: 9 years ago Posts: 103 |
I will print you a replacment part if you like and mail it to you. i live in Oklahoma, wouldnt be a problem.Quote
spinracing
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Wes78
Do you live in the us?
Yep, Florida.
Kicking myself for not printing extra parts.... resisting doing a Ax and buying another! (Dont have a business need yet.. so cant justify to the wife)
Re: Migbot Prusa i3 Unofficial Support Thread March 10, 2016 06:27AM |
Registered: 9 years ago Posts: 269 |
Re: Migbot Prusa i3 Unofficial Support Thread March 10, 2016 07:09AM |
Registered: 8 years ago Posts: 23 |
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Ax
As a note, when I finally sort my Mostly Printed CNC out, I'll be modelling out the frame for cutting in Aluminium plate, I will be offering these frames as a replacement for the Acrylic as well as a full Prusa i3 kit, the MetalMig. The MetalMig will be a Migbot, but my style with a metal frame, an E3D Lite6 Hot End and should hopefully just work out of the box.
Re: Migbot Prusa i3 Unofficial Support Thread March 10, 2016 09:50AM |
Registered: 8 years ago Posts: 23 |
Re: Migbot Prusa i3 Unofficial Support Thread March 10, 2016 09:52AM |
Registered: 9 years ago Posts: 269 |
Re: Migbot Prusa i3 Unofficial Support Thread March 10, 2016 10:02AM |
Registered: 8 years ago Posts: 23 |
Re: Migbot Prusa i3 Unofficial Support Thread March 10, 2016 10:13AM |
Registered: 9 years ago Posts: 11 |
Re: Migbot Prusa i3 Unofficial Support Thread March 13, 2016 03:54PM |
Registered: 8 years ago Posts: 23 |
Re: Migbot Prusa i3 Unofficial Support Thread March 13, 2016 05:04PM |
Registered: 8 years ago Posts: 23 |
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uberjay
Well, I'm back to a Thermal Runaway again.
Thought I had that licked... per Ax's recommendation I increased the thickness of the wire from the supply to the control board. Still need to do so for the bed, but I was getting some good prints. Now this... on a tiny 10 minute job.
Any ideas? I know... replace the bed wires... is it really that obvious a fix? I'm just curious because it is the hot end that is failing to hold temp.
Thanks,
Jason.
Re: Migbot Prusa i3 Unofficial Support Thread March 13, 2016 06:31PM |
Registered: 9 years ago Posts: 11 |
Re: Migbot Prusa i3 Unofficial Support Thread March 13, 2016 06:34PM |
Registered: 8 years ago Posts: 23 |
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jazzbassNick
I was using this shroud almost immediately since the one that came with it kept falling apart: [www.thingiverse.com]
Re: Migbot Prusa i3 Unofficial Support Thread March 14, 2016 12:01AM |
Registered: 9 years ago Posts: 31 |
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uberjay
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uberjay
Well, I'm back to a Thermal Runaway again.
Thought I had that licked... per Ax's recommendation I increased the thickness of the wire from the supply to the control board. Still need to do so for the bed, but I was getting some good prints. Now this... on a tiny 10 minute job.
Any ideas? I know... replace the bed wires... is it really that obvious a fix? I'm just curious because it is the hot end that is failing to hold temp.
Thanks,
Jason.
Okay... think I might have found a possible culprit. I manually turned down the fan speed to ~ 200 out of 244 (using the marlin 1.1 menus) while the hot end temp was declining and had dropped from 197 down to 183. After changing the fan speed the hot end temp climbed back up ... it's now at 188.
I think I saw somewhere maybe that someone was having issues with the stock fan shroud causing too much air on the hot end. Does anyone have a link to a part I can print to replace with a better nozzle?
Thanks!
J
Re: Migbot Prusa i3 Unofficial Support Thread March 14, 2016 07:04AM |
Registered: 8 years ago Posts: 23 |
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Canadian Geek
This is a modification I made of the same one as mentioned above. I did the modification so I could mount LEDs around the nozzle. Now my old eyes can see what I'm printing: [www.thingiverse.com]
Jeff
p.s. You may want to print it it ABS. I did it in PLA and it has warped a bit since. Nothing too bad but the next time I print it I'll be using ABS.
Re: Migbot Prusa i3 Unofficial Support Thread March 14, 2016 07:47AM |
Registered: 9 years ago Posts: 103 |
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uberjay
Okay... think I might have found a possible culprit. I manually turned down the fan speed to ~ 200 out of 244 (using the marlin 1.1 menus) while the hot end temp was declining and had dropped from 197 down to 183. After changing the fan speed the hot end temp climbed back up ... it's now at 188.
I think I saw somewhere maybe that someone was having issues with the stock fan shroud causing too much air on the hot end. Does anyone have a link to a part I can print to replace with a better nozzle?
Thanks!
J
Re: Migbot Prusa i3 Unofficial Support Thread March 14, 2016 10:13AM |
Registered: 8 years ago Posts: 24 |
Re: Migbot Prusa i3 Unofficial Support Thread March 14, 2016 06:06PM |
Registered: 8 years ago Posts: 23 |
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Wes78
Something isnt right.. as a test i pointed a fan + the cooling fan at my hotend and i dont have any problems with it keeping temperature. changing the fan shroud out may be a way to get by with it but really not the "fix"
I didnt read back to see, so just gonna ask right fast
Out of curiosity... have you done a PID tune on the hotend?
If you have, how many cycles did you run with PID auto tune?
after doing an auto tune, did you input the new numbers and do an auto tune again with the new numbers?
I would recommend doing PID auto tune 8-10 cycles updating with new numbers (kp, ki,kd) each time you auto tune. Auto tune attest 3 times or until you get the Kp,KI,and KD with in 5% of the previously set numbers getting the PID set correctly is VERY important to keep a stable hotend, the hotend "should" be able to over come the fan blowing on it and keep it stable.
there is a possibility that you have a some-what faulty heater cartage,( do you have a way to ohm it?) changing that out would seem like a better idea, maybe try to go up to a 40W one I think the one that comes with it is 30W
and as a last thought, have you made 100% sure you have entered in the FW that right thermometer settings ?
Re: Migbot Prusa i3 Unofficial Support Thread March 15, 2016 10:01AM |
Registered: 9 years ago Posts: 103 |
Re: Migbot Prusa i3 Unofficial Support Thread March 15, 2016 10:48AM |
Registered: 8 years ago Posts: 23 |
Re: Migbot Prusa i3 Unofficial Support Thread March 15, 2016 12:56PM |
Registered: 9 years ago Posts: 20 |
Re: Migbot Prusa i3 Unofficial Support Thread March 15, 2016 01:08PM |
Registered: 9 years ago Posts: 103 |
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CAlleman
Found this on Kickstarter today: [www.kickstarter.com]
Seems like it would be a good upgrade for the Migbot, thoughts?
Re: Migbot Prusa i3 Unofficial Support Thread March 15, 2016 01:34PM |
Registered: 14 years ago Posts: 50 |