Migbot Prusa i3 Unofficial Support Thread

What country is the fusebox guy in? I put in to be a beta user, not sure what requirements are. Also not sure what the kit would include.

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gotswrv
What country is the fusebox guy in? I put in to be a beta user, not sure what requirements are. Also not sure what the kit would include.

No idea, but the Fusebox is a self-build, self source jobbie, don't think AlexY or Culain are planning on production.. me on the other hand, possibly.

Sorry if this has been asked before but I couldn't find anything while searching.
Is there a replacement upgrade stepper motor available for these machines? Looking for something that's better but preferably plug and play.
Can anyone recommend anything?

Ax, on the fusebox site it shows beta kit and assembled(starting at $320). I put my name and email in the page and hit send.
Anyway, I'd like to support him, but it also depends on what a guy gets for the $$.

That fusebox looks neat, i like the cage setup to it tho, but im not a big fan on how the bed is set up as the z axis. I know other name brand printers are this way, i would really have to question the rigidity of the table thats a lot to support with 8mm rods. I have to much a machinist look on things i think lol


I started an open beam build with the one here [www.thingiverse.com]

I change it up some tho. i made it wider 300mmx200mm

Edited 2 time(s). Last edit at 02/11/2016 09:33AM by Wes78.

I'm really surprised that no-one has built a DIY 3D printer where the table is totally stationary like my CNC router. (or if they have, I just haven't seen it).

Jeff

I think the Z would be much better with some 12 or 15mm rods spaced a bit further apart.

The reason that the axis are not all stacked is all about how much weight you have to move and cost. In a router cnc you have a different set of goals and constraints. However in most mills the bed and spindle are not as a gantry. Gantrys are best suited to light duty, loose tolerance, large flat pattern parts.

The more I look at the fuse the more I'd like to tweak. Maybe I should try a couple things on the migbot then do my own design.

Quote
IBaz
Sorry if this has been asked before but I couldn't find anything while searching.
Is there a replacement upgrade stepper motor available for these machines? Looking for something that's better but preferably plug and play.
Can anyone recommend anything?

Something along the lines of this: [e3d-online.com] or this [www.aliexpress.com] would do

I'm courious..
Better how? Stronger, lighter, less current draw, etc.
What attributes would a better stepper have? What kind of performance improvements could be expected?

Never occurred to me that these steppers could be a bottleneck. If swapping them can help I'm in!

Quote
gotswrv
I'm courious..
Better how? Stronger, lighter, less current draw, etc.
What attributes would a better stepper have? What kind of performance improvements could be expected?

Never occurred to me that these steppers could be a bottleneck. If swapping them can help I'm in!

Holding torque is the key here, rapid stops and movements require a decent amount of torque to stop and not skip. Frankly the Busheng's on the Migbots I have are perfectly fine, they're somewhere in the region of 35 N-cm. One of mine has a 40N-cm on the extruder as one of the plug wires came loose and I didn't have a spare cable to replace it so I spliced it the 40 in as it's hard wired. Unless you're planning on putting a heavy carriage on somewhere, it's not really worth the upgrade..

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Ax

Quote
gotswrv
I'm courious..
Better how? Stronger, lighter, less current draw, etc.
What attributes would a better stepper have? What kind of performance improvements could be expected?

Never occurred to me that these steppers could be a bottleneck. If swapping them can help I'm in!

Holding torque is the key here, rapid stops and movements require a decent amount of torque to stop and not skip. Frankly the Busheng's on the Migbots I have are perfectly fine, they're somewhere in the region of 35 N-cm. One of mine has a 40N-cm on the extruder as one of the plug wires came loose and I didn't have a spare cable to replace it so I spliced it the 40 in as it's hard wired. Unless you're planning on putting a heavy carriage on somewhere, it's not really worth the upgrade..

Exactly, more torque. My Y-axis stepper is skipping like crazy no matter what I do. It started off fine and ran for months without problem but now just seems to be getting progressively worse. I have adjusted and tweaked everything but with every print now I have trouble. Assuming that the OEM steppers are pretty light on (I don't know what their specs are) there must be a simple upgrade available. What sort of spec should I be looking for?

Edited 1 time(s). Last edit at 02/11/2016 07:40PM by IBaz.

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IBaz

Quote
Ax

Quote
gotswrv
I'm courious..
Better how? Stronger, lighter, less current draw, etc.
What attributes would a better stepper have? What kind of performance improvements could be expected?

Never occurred to me that these steppers could be a bottleneck. If swapping them can help I'm in!

Holding torque is the key here, rapid stops and movements require a decent amount of torque to stop and not skip. Frankly the Busheng's on the Migbots I have are perfectly fine, they're somewhere in the region of 35 N-cm. One of mine has a 40N-cm on the extruder as one of the plug wires came loose and I didn't have a spare cable to replace it so I spliced it the 40 in as it's hard wired. Unless you're planning on putting a heavy carriage on somewhere, it's not really worth the upgrade..

Exactly, more torque. My Y-axis stepper is skipping like crazy no matter what I do. It started off fine and ran for months without problem but now just seems to be getting progressively worse. I have adjusted and tweaked everything but with every print now I have trouble. Assuming that the OEM steppers are pretty light on (I don't know what their specs are) there must be a simple upgrade available. What sort of spec should I be looking for?

My memory is terrible and I'm pre-first Coffee, you running an Aluminium carriage that's heavier than the 5mm Acrylic one? If not, it may actually be the stepper driver on the board. There's a way to test.. in pins.h or in pins_RAMPS_13.h if using my Marlin firmware 1.1 look for the following:

    #define Y_STEP_PIN         60
    #define Y_DIR_PIN          61
    #define Y_ENABLE_PIN       56

and

    #define E1_STEP_PIN        36
    #define E1_DIR_PIN         34
    #define E1_ENABLE_PIN      30

In Marlin 1.0's pins.h, you're looking for the Arduino Mega pin assignment section as it's all lumped into one file. Swap the pin numbers around, reflash and plug the Y stepper motor into the E1 port on the board, Print, check for skips and if no skips, it's the Stepper driver..

Edited 1 time(s). Last edit at 02/12/2016 02:41AM by Ax.

Thanks Ax but referring to my last problem I can't talk to the board to change firmware. My new board actually arrived just today (MKS Base V1.4) so am yet to give it a go so it may even fix this problem also.
I have the large bed with a Trespa carriage. Slightly lighter than the Acrylic but super stiff. This also has four bearings so eliminates the slight yaw I was getting with only three bearings. With printed bearing mounts and 6mm cork insulation under the heat bed it works out around the same weight as the original when I had no trouble.
With the height detection I have hard mounted the aluminum build plate to the carriage and eliminated bounce from the springs. I theorize now that the entire carriage is stiff and has no flex, this puts more strain on the stepper motor as the entire force of the Y axis movement is against it where as before this would be absorbed by the flexing in the acrylic frame, yaw of the carriage and bounce in the springs. Not sure but it seems to be more harsh in direction changes than before.
A stronger stepper motor can't be a bad thing anyway

I was looking at either this:
38mm Stepper Motor
Which claims 43.2N-cm

Or this one:
40mm Stepper Motor
Which claims 50N-cm

I don't quite understand all the spec jargon so don't know if these are OK, or are just going to fry something else.

2 questions for you

1. What is your acceleration set at?

2. Have you tried to up the drive current?

Quote
IBaz
Thanks Ax but referring to my last problem I can't talk to the board to change firmware. My new board actually arrived just today (MKS Base V1.4) so am yet to give it a go so it may even fix this problem also.
I have the large bed with a Trespa carriage. Slightly lighter than the Acrylic but super stiff. This also has four bearings so eliminates the slight yaw I was getting with only three bearings. With printed bearing mounts and 6mm cork insulation under the heat bed it works out around the same weight as the original when I had no trouble.
With the height detection I have hard mounted the aluminum build plate to the carriage and eliminated bounce from the springs. I theorize now that the entire carriage is stiff and has no flex, this puts more strain on the stepper motor as the entire force of the Y axis movement is against it where as before this would be absorbed by the flexing in the acrylic frame, yaw of the carriage and bounce in the springs. Not sure but it seems to be more harsh in direction changes than before.
A stronger stepper motor can't be a bad thing anyway

I was looking at either this:
38mm Stepper Motor
Which claims 43.2N-cm

Or this one:
40mm Stepper Motor
Which claims 50N-cm

I don't quite understand all the spec jargon so don't know if these are OK, or are just going to fry something else.

Yeah, I was pre- coffee and had just woken up. Get the board in upload my firmware if you can connect to to board, Try a print. I guarantee there will be no real need to upgrade the motor, the acceleration is low, but with a ally carriage it can be pushed to around 2000. I have pretty much the exact same set-up on my 3 and I'm still using the stock motors and getting damn good quality prints. Personally, don't spend money if you don't have to and this is really a case that you don't have to.

Since I change my acceleration rate to 1600 and up the drive voltage to 1 volt I haven't had any skip steps pushing the drive to 1 volt I recommend a heat sink anf active cooling on the drive

Edited 1 time(s). Last edit at 02/12/2016 12:49PM by Wes78.

Quote
Wes78
2 questions for you

1. What is your acceleration set at?

2. Have you tried to up the drive current?

Wes,

1. Acceleration is still factory. I have not changed anything in the firmware at all.

2. Don't know how to do this and have no idea how to check what it is set at now.


All good Ax, I was going to try your firmware but as I have never been down this path before have been a bit hesitant to change anything for fear of making things worse or damaging something. I have to do something now as I need to get this new board up and running.

Out of curiosity though would either of the Stepper Motors I listed be ok for this machine? Just like to know if my thinking is right, cheers.

Edited 1 time(s). Last edit at 02/12/2016 04:27PM by IBaz.

Greets all,

Long time (well since I got my Electron 3d i3 in September '15) reader, first time poster here. I'd like to thank everyone that's been so helpful in this thread. Kept me from dropkicking it a few times

I recently ran into an issue where the extruder motor would just rotate back and forth instead of extruding. Hooked the motor up to the X driver and it worked great. Hooked my X axis up to the E0 driver, and it exhibited the same issue as the extruder. I figured no prob, re-configure the pins to use E1 (thanks for the tips there too). E1 worked great for about 5 mins and now it's exhibiting the same behavior.

The drivers on this MKS 1.3 are 4982s. I've tried re-flashing several times (both before and after my changes to pins.h).

Am I totally screwed or do you guys have some ideas what I should try?

Thanks,
jbN

Quote
IBaz

Quote
Wes78
2 questions for you

1. What is your acceleration set at?

2. Have you tried to up the drive current?

Wes,

1. Acceleration is still factory. I have not changed anything in the firmware at all.

2. Don't know how to do this and have no idea how to check what it is set at now.

no problem I'll help, look for this bit with in your firmware . you can chang what diffarnt in yours and give that a try

//// MOVEMENT SETTINGS
#define NUM_AXIS 4 // The axis order in all axis related arrays is X, Y, Z, E
#define HOMING_FEEDRATE {50*60, 50*60, 4*60, 0} // set the homing speeds (mm/min)

// default settings

#define DEFAULT_AXIS_STEPS_PER_UNIT {80,80,401.6860355283,100.4383343295} // default steps per unit for ultimaker //78.7402, 78.7402,1070,865.88
#define DEFAULT_MAX_FEEDRATE {200, 200, 10, 25} // (mm/sec)
#define DEFAULT_MAX_ACCELERATION {1590,1590,100,10000} // X, Y, Z, E maximum start speed for accelerated moves. E default values are good for skeinforge 40+, for older versions raise them a lot.


#define DEFAULT_ACCELERATION 1590 // X, Y, Z and E max acceleration in mm/s^2 for printing moves
#define DEFAULT_RETRACT_ACCELERATION 1590 // X, Y, Z and E max acceleration in mm/s^2 for retracts





to tune the drive watch this video here [www.youtube.com]

Good luck!


Edit dont change the step_per_unit, keep what you have as mine may be different

Edited 1 time(s). Last edit at 02/12/2016 04:37PM by Wes78.

Quote
jazzbassNick
Greets all,

Long time (well since I got my Electron 3d i3 in September '15) reader, first time poster here. I'd like to thank everyone that's been so helpful in this thread. Kept me from dropkicking it a few times

I recently ran into an issue where the extruder motor would just rotate back and forth instead of extruding. Hooked the motor up to the X driver and it worked great. Hooked my X axis up to the E0 driver, and it exhibited the same issue as the extruder. I figured no prob, re-configure the pins to use E1 (thanks for the tips there too). E1 worked great for about 5 mins and now it's exhibiting the same behavior.

The drivers on this MKS 1.3 are 4982s. I've tried re-flashing several times (both before and after my changes to pins.h).

Am I totally screwed or do you guys have some ideas what I should try?

Thanks,
jbN

I cant say for sure what the deal is with out checking out the motor,

But to me it sounds like you have an issue with that motor, and burned up the drive, when you switched to the other (E1) sounds like it got it too, but that what it sounds like to me. i may be wrong

On a good note a new control board isn't that expensive, i had just got a mks gen v1.4 (listed as a v1.3) its set up so you can change out the stepper drives, ( and can do 1/32 stepping if you feel Skippy) was 50$ free shipping from amazon

Quote
Wes78
I cant say for sure what the deal is with out checking out the motor,

But to me it sounds like you have an issue with that motor, and burned up the drive, when you switched to the other (E1) sounds like it got it too, but that what it sounds like to me. i may be wrong

On a good note a new control board isn't that expensive, i had just got a mks gen v1.4 (listed as a v1.3) its set up so you can change out the stepper drives, ( and can do 1/32 stepping if you feel Skippy) was 50$ free shipping from amazon

Thanks Wes. I hadn't considered the motor was the creating the issue. What would you do to "check out" the motor? I've read a couple of debates about opening them up.
You get the Hictop?

I would just ohm it out with a voltmeter.
You'll have to look up the motor info.

If it had gotten hot there's a chance that it is starting to get an internal short. Chances are taking apart you may never see anything

Motors are dirt cheep... if it was me I'd probably get one and see if it changes. If it don't then you'll always have a back up motor.

I have the electron

Edited 2 time(s). Last edit at 02/12/2016 05:06PM by Wes78.

Thanks for that.
I meant which board did you order? Heehee
Ohms start around 1.6 on both phases but fluctuate more than the +/- 10%.

Looks like the driver is OK on the board E1 moved my X as it should.

Gonna try a new motor and see how that fares.
Thanks again!

The +/- 10% definitely bothers me.

Good luck I hope it works out for you.


This is the one I got. [www.ebay.com]

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IBaz

Quote
Wes78
2 questions for you

1. What is your acceleration set at?

2. Have you tried to up the drive current?

Wes,

1. Acceleration is still factory. I have not changed anything in the firmware at all.

2. Don't know how to do this and have no idea how to check what it is set at now.


All good Ax, I was going to try your firmware but as I have never been down this path before have been a bit hesitant to change anything for fear of making things worse or damaging something. I have to do something now as I need to get this new board up and running.

Out of curiosity though would either of the Stepper Motors I listed be ok for this machine? Just like to know if my thinking is right, cheers.

Basically my configs, all you need to do is PID tune and Calibrate the Steps/mm on the extruder and you should be away. If you're not sure, give me a shout. Personally I'd go for 40N-cm+ to make sure, which both are, and tbh they'd both work.

Well, I was having trouble getting the bed up to ABS temps and thought I had fuse troubles. It could warm up for PLA an about 15-20 minutes, but was unable to reach 100C. Testing didn't show anything other than software being upset about poor control over temp. Put an insulation pad on top and bottom of the bed and it heated right up. So in my pea brain this means I'm not getting enough wattage for the PID to work without tripping the software safety's. Kinda got a wild hair and wired the bed to 24v.
At 24v I encountered a slight smell and was able to heat from 12C to 216C in about 3-1/2 minutes. The temp would hunt a little over and undershooting, this coupled with the smell prompted me to lower the volts to about 19.. I added an insulation pad under the bed (some kind of ceramic cushion mat used in space heaters) Now it takes about 5 minutes to come up to temp and I've not noticed it ever wavering from commanded. No scary smells either.
I did not rewire the board, it is still setup for 12v. Not sure how unsafe this is, or if it should be attempted by others.
A side effect seems to be I need to retune the extruder as it is fluctuating enough to trip the thermal runaway alarm. Guess the 12V side has a lot more to work with now. Should be an improvement in fan performance, stepper holding power, etc.

I'm not suggesting you do this, it is quite likely that what I've done might cause a future failure. Burn down the house, cost me the printer, whatever..


What I did was grab up a 24v 20a supply I had laying around. Unhook the positive bed lead from the control board (the board only controls the negative side). Wire a fuse into the positive off the 24v supply into the positive wire of the bed (I chose a 15a fuse). Again, the positive from the 24v to the bed will no longer be attached to the board (wire nut it all by itself). The negative lead from the 24 supply goes to the negative of the 12v supply. I suggest using an adjustable 24v supply with the voltage set as low as it will go (mine is 19v)
Tune the PIDs


[www.infraredheaters.com]
[www.ebay.com]
[www.ebay.com]

Just a follow-up to my motor issue:
Extruder is hooked up, just not attached in the carriage, sitting sideways with a piece of filament in it. If I apply a little tension to the filament (either pushing from above or pulling from below, just a little), the shaft rotates and advances the filament. Without me applying any tension, the shaft just rotates back and forth.

Hoping to swing by Deezmaker's shop and that they have a motor I can buy, otherwise I'll have to wait for Amazon.

Just thought I'd add this latest observation in case it jogs any ideas for anyone.
Cheers,
N

Edited 1 time(s). Last edit at 02/14/2016 04:29PM by jazzbassNick.

I have a developing issue that I hope you can help me with.

I have been beautifully for a while now. Now all of a sudden the rafts won't separate from the prints, (yes I use rafts on PLA prints so I don;t get blue tape mess on the bottom of the items).

I print off the SD card using the same files. Printed an item couple days ago, wonderful. Printed the same item today, and the raft wont separate. Any suggestions as to what is going on?


Thanks in advance.

Quote
veaceonee
I have a developing issue that I hope you can help me with.

I have been beautifully for a while now. Now all of a sudden the rafts won't separate from the prints, (yes I use rafts on PLA prints so I don;t get blue tape mess on the bottom of the items).

I print off the SD card using the same files. Printed an item couple days ago, wonderful. Printed the same item today, and the raft wont separate. Any suggestions as to what is going on?


Thanks in advance.

That's more than likely a filament issue over a printer issue. Check the filament diameter would be the first step..

Quote
gotswrv
Well, I was having trouble getting the bed up to ABS temps and thought I had fuse troubles. It could warm up for PLA an about 15-20 minutes, but was unable to reach 100C. Testing didn't show anything other than software being upset about poor control over temp. Put an insulation pad on top and bottom of the bed and it heated right up. So in my pea brain this means I'm not getting enough wattage for the PID to work without tripping the software safety's. Kinda got a wild hair and wired the bed to 24v.
At 24v I encountered a slight smell and was able to heat from 12C to 216C in about 3-1/2 minutes. The temp would hunt a little over and undershooting, this coupled with the smell prompted me to lower the volts to about 19.. I added an insulation pad under the bed (some kind of ceramic cushion mat used in space heaters) Now it takes about 5 minutes to come up to temp and I've not noticed it ever wavering from commanded. No scary smells either.
I did not rewire the board, it is still setup for 12v. Not sure how unsafe this is, or if it should be attempted by others.
A side effect seems to be I need to retune the extruder as it is fluctuating enough to trip the thermal runaway alarm. Guess the 12V side has a lot more to work with now. Should be an improvement in fan performance, stepper holding power, etc.

I'm not suggesting you do this, it is quite likely that what I've done might cause a future failure. Burn down the house, cost me the printer, whatever..


What I did was grab up a 24v 20a supply I had laying around. Unhook the positive bed lead from the control board (the board only controls the negative side). Wire a fuse into the positive off the 24v supply into the positive wire of the bed (I chose a 15a fuse). Again, the positive from the 24v to the bed will no longer be attached to the board (wire nut it all by itself). The negative lead from the 24 supply goes to the negative of the 12v supply. I suggest using an adjustable 24v supply with the voltage set as low as it will go (mine is 19v)
Tune the PIDs


[www.infraredheaters.com]
[www.ebay.com]
[www.ebay.com]

The way I'm reading this says you have no separation of the 2 supplies. THIS IS BAD You either need a MOSFET or SSR to separate the power from the board which switches at 12v, btw, so you're giving the MK2B heat pad over 24v and putting stress on the motherboard, unless you want an electronics fire on your hands put it back to how it was and get a SSR or correct MOSFET to isolate the board. You'll then be able to use a 24v supply to power the bed.