My build
Re: My build
It depends a little on the ambient lightning and the type of boards you are using, but in general, no. The diffuser was supplied with one set of spacers which is what I use, and I suspect it is good enough in most cases. You also got another set of spacers, but you don't have to use them.
Re: My build
You actually need the extra spacers, otherwise the diffuser will touch the skew bolts and press them up.
Re: My build
Strange.
After homing moving to zero pcb works nice:
Moving most back left and back to zero pcb:
Moving 20cm to the right and back to zero pcb:
Moving back to most back left to zero pcb:
After homing moving to zero pcb works nice:
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Re: My build
Exactly the same symptoms as the problem I was having.
Check out my post about cable ties being used on the belt attachment points, it may look okay visibly,
but unless you happened to get lucky, it’s hiding from view underneath where you can’t see it if you followed
the standard build instructions. It shows up as a kind of variable backlash and is quite large.
Once you have that solved, anything remaining is backlash, and you want backlash compensation enabled.
With the caveat, that if like mine it doesn’t give you the precision you need, you may need to use more than the 0.4mm
backlash that’s in Liteplacer, in which case:
1. If you wish to stay with Liteplacer, I have a compiled binary you can have which allows you to change the amount of
Backlash Compensation, it’s a drop in replacement for your .exe
OR
2. Switch to OpenPNP which enables you to specify the amount by default
Check out my post about cable ties being used on the belt attachment points, it may look okay visibly,
but unless you happened to get lucky, it’s hiding from view underneath where you can’t see it if you followed
the standard build instructions. It shows up as a kind of variable backlash and is quite large.
Once you have that solved, anything remaining is backlash, and you want backlash compensation enabled.
With the caveat, that if like mine it doesn’t give you the precision you need, you may need to use more than the 0.4mm
backlash that’s in Liteplacer, in which case:
1. If you wish to stay with Liteplacer, I have a compiled binary you can have which allows you to change the amount of
Backlash Compensation, it’s a drop in replacement for your .exe
OR
2. Switch to OpenPNP which enables you to specify the amount by default
Re: My build
I have been playing around. It is allways a offset of 0.1mm, if you make a move to the opposite direction it is gone. Try your solution later this day.
Re: My build
Tried the mod on the X axis, no luck. The strange thing is that the fault occurs only after a positive movement on the X or Y axis. But it always stays at 0.1mm, only a negative move corrects this.
Re: My build
So if you've made the zip tie mods here, with the small zip ties:
https://liteplacer.com/phpBB/viewtopic. ... 9&start=40
and it made no difference, then the first thing I'd suggest to remove one attachment, and simulate the new attachment method
around something small/flat so you can inspect and play around pulling and pushing on it to see if there's any tooth shift at all.
Seems crazy to look at it again, but I'd looked at mine many times and couldn't see the issue until I removed it, it can be tight on one side of
the assembly and loose on the other. There's still a possibility your cable ties are less flexible than mine, in which case you'll need an alternative
attachment method.
That's the most likely cause.
Failing that, check the belt tension, it should be fairly loose, by loose I mean as tight as you can tension the stepper with 2 fingers outstretched on the diagonals. Too tight and the backlash increases, also too loose and it increases. It's a surprising amount of looseness.
Also check at the attachment point on X, that the groove in a tooth is sitting on the corner, so it locks the belt to the plate.
You should have backlash compensation on (I'm using 1.4mm and have a custom binary, I found 0.4mm wasn't enough). I've also replaced my belt for a slight improvement over the stock belt (probably around 0.02mm)
I'm down to 0.02mm backlash in X and Y with backlash compensation on.
https://liteplacer.com/phpBB/viewtopic. ... 9&start=40
and it made no difference, then the first thing I'd suggest to remove one attachment, and simulate the new attachment method
around something small/flat so you can inspect and play around pulling and pushing on it to see if there's any tooth shift at all.
Seems crazy to look at it again, but I'd looked at mine many times and couldn't see the issue until I removed it, it can be tight on one side of
the assembly and loose on the other. There's still a possibility your cable ties are less flexible than mine, in which case you'll need an alternative
attachment method.
That's the most likely cause.
Failing that, check the belt tension, it should be fairly loose, by loose I mean as tight as you can tension the stepper with 2 fingers outstretched on the diagonals. Too tight and the backlash increases, also too loose and it increases. It's a surprising amount of looseness.
Also check at the attachment point on X, that the groove in a tooth is sitting on the corner, so it locks the belt to the plate.
You should have backlash compensation on (I'm using 1.4mm and have a custom binary, I found 0.4mm wasn't enough). I've also replaced my belt for a slight improvement over the stock belt (probably around 0.02mm)
I'm down to 0.02mm backlash in X and Y with backlash compensation on.
Re: My build
Did some testing with the aim pcb file. Probe down is always spot on! Even moving to the right back of the machine en back to the aim. Sometimes the camera cross is not spot on, but the probing is! I think there is some issue with the actual picture on the screen.
Maybe Yuha can shed some light on this?
Maybe Yuha can shed some light on this?
Re: My build
I have allways a small shift to the right. Resistor is picked from tape and the ic as loose part. Changing the nozzle distance does not compensate it ( only the part is picked up at a different point), what am I doing wrong?
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Re: My build
Same result with a real pcb:
Please help!
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Please help!