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engraving problem backlash

Posted: Thu May 09, 2019
by Dominik Kop
i have a problem with the backlash setting
I set it for one object and it's OK
but as there are several objects, the side ones are OK, but the ones between do not have an even line
Where is the problem ?

Re: engraving problem backlash

Posted: Thu May 09, 2019
by Jeffrey Aley
How are you adjusting the backlash? I mean, what are you changing in the software to adjust the backlash?

I am asking this because there are two places to adjust it. But someone (I think it was Pete Cyr) pointed out that one of them isn't really for backlash - it's to compensate for the delay in the high voltage power supply.

Backlash is shown on the "User" tab when you select "Other" (this is for RD Works 8.01.24). For my 500x300 machine, I set Backlash X(mm) to 0.200 and Backlash Y(mm) to 0.275. This affects both cutting and rastering.

The other one (power-supply delay) is set on the Config -> System Setting window. This has the reverse interval and offset repay (offset compensation). The reverse interval tells the power supply to fire a little bit early so that the signal is actually at the right voltage at the right time. The offset compensation is there to shift the whole raster in one direction or the other so that it aligns with your vector cuts, etc.

Regards,

-Jeff

Re: engraving problem backlash

Posted: Thu May 09, 2019
by Dominik Kop
you're right
I set in config-> general setting-> scanning
can you explain more to me about reverse interval and offset repay?
How should it be set up?

Re: engraving problem backlash

Posted: Thu May 09, 2019
by Dominik Kop
as it is described here

http://www.thunderlaser.com/troubleshoo ... swing.html

it works and I can set one object to make lines equal.
But as there are several side-by-side photos you see in the picture above in the first post as it comes out

Re: engraving problem backlash

Posted: Thu May 09, 2019
by Dominik Kop
if I understand it right now, I have to set a good backlash first
user->other ....
and then later
Config -> System Setting window.
because the setting scanning interrupt does not make sense if the backlash is not set?

Re: engraving problem backlash

Posted: Thu May 09, 2019
by Jeffrey Aley
Dominik Kop wrote: Thu May 09, 2019 if I understand it right now, I have to set a good backlash first
user->other ....
and then later
Config -> System Setting window.
because the setting scanning interrupt does not make sense if the backlash is not set?
Correct. I find it best to calibrate the backlash using vector cuts. Then, once that is done, you can use the Config -> System Setting to calibrate the raster (as you are doing in the pictures you sent).

To calibrate the backlash, I followed the instructions here: http://atklaser.co.uk/2016/11/21/battle ... -backlash/ .
I actually used a magnifying glass to ensure very high precision.

The other pattern I used was an array of very closely spaced squares (each square ~15mm), spacing only 1mm apart. I could see very clearly that some squares weren't in the right places until the backlash was corrected.

Re: engraving problem backlash

Posted: Thu May 09, 2019
by Pete Cyr
viewtopic.php?f=105&t=3528#p20418

Read the link above - download the pdf and review the info in the pdf

Cut a 100x100mm square an measure to determine the accuracy of you gantry movement - if the measurement is off much you will also experience the issue you describe with the center engravings.

Re: engraving problem backlash

Posted: Fri May 10, 2019
by Dominik Kop
I have a problem
I'm trying to set a backlash
User "tab when you select" Other "
press read o enter the value of 0.10 press write
no effect, I press read again and pops up 0.00
as if I did not load my change

Re: engraving problem backlash

Posted: Fri May 10, 2019
by Dominik Kop
OK, I was able to set it
backlash x 0.10
scanning reverse - 0.039
below photo settings
what do you think are OK?

Re: engraving problem backlash

Posted: Fri May 10, 2019
by Jeffrey Aley
Looks very good!