Problem : Lost same steps in x/y
Hallo @ all
I have a problem with my MK2 printer. He always loses the same steps in the X and Y. If I print a block with 50x50mm then he prints 49.8x49.8 if i print 110x110mm he make 109.6x109.6mm . It is the same for every print. Even if I move x or y with hand, I have the same error. I use the firmware 3.0.8 and i have the printer reset to factory settings, re-calibrated and check the parts of the printer but it does not help. I always have the same problem. Every 10mm I have 0.04mm less. The print is perfect but too small.
I have test the same STL on my MK1 and it´s work.
At Z I have no problems here agree the measures.
I have unfortunately no idea what that could be, I hope you can help me.
Re: Problem : Lost same steps in x/y
Kai
That is pretty good; I don't think you should be complaining!
There are a couple of things you could do; try printing perimeters first, slow down the print and if all else fails, change the steps/mm - there are plenty of posts detailing how to do this.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Problem : Lost same steps in x/y
Hallo Peter
Thanks for the quick help. (change the steps/mm)
But i am sorry, every 10mm 0,04mm less is for me not good.
My Mk1 print a 180mm x180mm block with 179.8mm x 179.8mm that is ok.
My Mk2 print with 179.1 x 179.1
I see at the Mk1 that Prusa can make it better.
But now i try the M92. At the first moment it look realy great with the hand step now 100mm = 99.95mm 😀
Yes and now is the print perfect.
Thank so much
Re: Problem : Lost same steps in x/y
The problem is that GT2 belts (especially Chinese ones) don't usually have accurate tooth pitch. Should be 2mm/tooth, but when I measured new belt, 100 teeth was 199.5mm not 200mm. Firmware relies on this value. When this happen, firmware configuration must be adjusted accordingly, that's why there is M92 command. 😉
I've created this calibration object recently http://www.thingiverse.com/thing:1818250
It usually takes only one test print to adjust steps/mm to correct values.
Re: Problem : Lost same steps in x/y
[quote="david.t2"100 teeth was 199.5mm not 200mm.[/quote]
David
That is to allow for stretching and tight belts. Kai may have slightly over tightened and caused the difference.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Problem : Lost same steps in x/y
Kai may have slightly over tightened and caused the difference.
I don't think so. His prints come out smaller than intended, it means belts have teeth closer to each other than 2mm. Exactly what I measured.
BTW you need really extreme force to stretch GT2 belt. I tried to make it stretched to 2mm per tooth (200mm per 100 teeth) on Y axis. The force was so strong it made 8mm threaded rods on Y frame bended together. Unusable.
Re: Problem : Lost same steps in x/y
His prints come out smaller than intended, it means belts have teeth closer to each other than 2mm.
David
You may want to review that.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Problem : Lost same steps in x/y
Allright, once again.
The firmware relies on the fact, that tooth pitch of GT2 belt is 2mm per tooth.
So if you want to make 100mm move, the pulley must pass 50 teeth.
If GT2 tooth pitch is smaller (less than 2mm per tooth, teeth closer to each other), it makes shorter move = printed objects come out smaller.
Re: Problem : Lost same steps in x/y
Is there a better quality belt upgrade?
Re: Problem : Lost same steps in x/y
I guess supplying and making stuff at home and not relying on China for parts, may be good for the West. When will we ever learn? Bottom dollar is often not top quality. Lets make things at home again. Bring home manufacturing and quality products and parts.
Nigel
Life is keeping interested and excited by knowledge and new things.
Re: Problem : Lost same steps in x/y
You hardly convince somebody to use belt for $30 when there is belt for $2 and the only visible difference is numeric constant used in software. It's sad but it's reality.