UM2 Y axis losing steps

[Kirbs 0]

@phantom I just did that, but those pulleys don't seem to be the problem as I find out from the marker test. How can I do this process on the stepper pulley? I pushed them all apart and some definitely had some space to move. Hopeful this will fix it?

39 minutes ago, phantom said:

Loosen the pulleys, push the rods in from the back or the side, depending on which axis your working on,push the pulley to the the side it is sitting at with your other hand while tighten the screw. 

Push as per the arrow in the picture:

 

 

Edited March 31, 2018 by Kirbs

[Kirbs 0]

1 hour ago, Kirbs said:

@phantom I just did that, but those pulleys don't seem to be the problem as I find out from the marker test. How can I do this process on the stepper pulley? I pushed them all apart and some definitely had some space to move. Hopeful this will fix it?

 

After trying to print something I ended up getting layer shifting in the second layer? Ask the pulleys are tight and not moving at all. Perhaps it's not a problem with the pulleys?

 

Update: I don't know if this is a different problem but it's new, now it's not even printing the beginning layers right. It managed to print around 50 layers before issue before I pushed the pulleys, now it can hardly do three and it starts popping.

@phantom

Edited March 31, 2018 by Kirbs

[gr5 2,173]

I would mark the actual stepper.  It's more work but we need to figure this out.  High friction can also caused missed steps.  Overheating of the stepper driver can cause missed steps.  Is the room that the printer in very hot?  Like 30C?  If not I still think it's most likely your stepper pulley is slipping.  Completely take the stepper out.  The Y stepper.  Tighten the set screw well while it's out but also mark the shaft and the pulley and maybe take a photo of that for reference for yourself to see if it slips.  Put it all back together.  If it slips again, take that motor out again and see if it slipped.

[Kirbs 0]

20 minutes ago, gr5 said:

I would mark the actual stepper.  It's more work but we need to figure this out.  High friction can also caused missed steps.  Overheating of the stepper driver can cause missed steps.  Is the room that the printer in very hot?  Like 30C?  If not I still think it's most likely your stepper pulley is slipping.  Completely take the stepper out.  The Y stepper.  Tighten the set screw well while it's out but also mark the shaft and the pulley and maybe take a photo of that for reference for yourself to see if it slips.  Put it all back together.  If it slips again, take that motor out again and see if it slipped.

I will do this immediately, the room the printer is confined in is about the size of a dog cage, but I doubt it gets too hot as I leave the door open.

 

Update:

The screw inside the stepper seemed pretty warped, I wasn't able to tighten or loosen it, but I'm pretty positive it's tight because I cranked it yesterday, am running a test print now I guess we'll see

 

 

Many thanks

Edited March 31, 2018 by Kirbs

[Kirbs 0]

Another print failed it was going well until a small skip. The stepper shows no signs of skipping. All the marker lines up. Maybe it isn't the pulleys?

It was on the y axis again, the skipping.

 

What could be causing this if it isn't my pulleys?

Or have I marked my stepper wrong @gr5 @phantom?

Update

So I was thinking about it and maybe it is getting to hot. The first skip is a couple hours after I shut the door and went to bed, this it had no chance to cool down, and i don't think it'd be to hard for the build plate to bring the room up to 30º.

Could it be an issue with the end stops getting triggered unexpectedly?

Edited April 1, 2018 by Kirbs
Update

[phantom 17]

Maybe try the same print while the printer is in a bigger room so you can rule out if it's the high temps

[Torgeir 242]

Hi Kirbs,

 

Just another possible issue here, did you check the stepper motor current? To lo current can create missed step if there is some friction involved.

Have a look at the firmware setting on the printer setup menu, think it is under speed settings..

If my memory serve well, the current setting should be around ~1250 mA for those kind stepper motors.

 

Just a thought.

 

Good luck.

 

Torgeir

[Kirbs 0]

1 hour ago, Torgeir said:

Hi Kirbs,

 

Just another possible issue here, did you check the stepper motor current? To lo current can create missed step if there is some friction involved.

Have a look at the firmware setting on the printer setup menu, think it is under speed settings..

If my memory serve well, the current setting should be around ~1250 mA for those kind stepper motors.

 

Just a thought.

 

Good luck.

 

Torgeir

Sorry how exactly do I check that, do I need to upload custom firmware @Torgeir? 

[Torgeir 242]

Hi Kirbs,

 

Firmware is just the "program" installed into the Arduino board that is controlling your printer.

You just switch on your printer and select from the menu "Maintenance" then go to "advanced menu", then roll down to speed setting and enter.

If you roll down in here you will find speed setting and the various stepper motor current setting (X,Y,Z & EXR1 (+EXTR2 not in use)).

 

Here the current can be adjusted, but do not rice this setting if it is correct -as to high setting here can ruin your main electronic board.

 

Often when stepper motors fail, it is due to high friction internally when the motor is at working temperature, rising current will create more heat in the motor and also increase the temperature on your controlling PCB (the expensive main electronic board).

 

Thanks.

 

Torgeir

 

 

 

 

 

[Kirbs 0]

19 minutes ago, Torgeir said:

Hi Kirbs,

 

Firmware is just the "program" installed into the Arduino board that is controlling your printer.

You just switch on your printer and select from the menu "Maintenance" then go to "advanced menu", then roll down to speed setting and enter.

If you roll down in here you will find speed setting and the various stepper motor current setting (X,Y,Z & EXR1 (+EXTR2 not in use)).

 

Here the current can be adjusted, but do not rice this setting if it is correct -as to high setting here can ruin your main electronic board.

 

Often when stepper motors fail, it is due to high friction internally when the motor is at working temperature, rising current will create more heat in the motor and also increase the temperature on your controlling PCB (the expensive main electronic board).

 

Thanks.

 

Torgeir

 

 

 

 

 

O man I was messing around in Cura trying to find this setting, it was set to 1300 mA, I turned it down so I guess we'll see how it helps

 

Many thanks

[gr5 2,173]

5 hours ago, Kirbs said:

it was set to 1300 mA

Woah!  I thought it was supposed to be around 900 or 1000?  I've never had to mess with this though.

 

You won't damage anything by having the current too high.  The stepper automatically shuts off for a few milliseconds and you get what looks like a slipping pulley.  Sorry - I've been telling you to tighten the pulleys and now it seems maybe your stepper drivers are getting too hot.  You could alternatively remove the bottom cover and add a desk fan nearby and tilt the machine.  But let me go look up what the current should be.

 

Mine are set to 1200ma on both my UM2 and my um2go.  I never touched them.  I think UM recommends lower current in hotter climates - around 1000ma.  If you lower it too much the high acceleration at the lower current will *also* caused missed steps.  1000 to 1200ma should be about right.

[Kirbs 0]

14 minutes ago, gr5 said:

Woah!  I thought it was supposed to be around 900 or 1000?  I've never had to mess with this though.

 

You won't damage anything by having the current too high.  The stepper automatically shuts off for a few milliseconds and you get what looks like a slipping pulley.  Sorry - I've been telling you to tighten the pulleys and now it seems maybe your stepper drivers are getting too hot.  You could alternatively remove the bottom cover and add a desk fan nearby and tilt the machine.  But let me go look up what the current should be.

 

Mine are set to 1200ma on both my UM2 and my um2go.  I never touched them.  I think UM recommends lower current in hotter climates - around 1000ma.  If you lower it too much the high acceleration at the lower current will *also* caused missed steps.  1000 to 1200ma should be about right.

Jeez, i have no clue how it could've gotten so high, must've switched up when I updated my firmware. Fantastic we finally got this sorted though. Thank you so much @gr5 for helping me sort this out, and staying with me through out the process.

 

Many thanks