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Machine steps are 8 times larger than they should be

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20 Apr 2023 18:55 #269503 by felucho
Hello:
This is my first post and my first experience with LINUXCNC.  I designed and built the machine myself.
In my first test with AXIS things seemed to work but the physical steps are 8 times larger than they should be.
I am using 5mm per revolution lead screws. Motors (1.8 deg/step) directly coupled to lead screws. MD430 motor drives set at 16 microsteps.

Then I changed in stepconfig to 2 microsteps (without changing the MD430) and the steps have the right size but runs rougher.
I am attaching the hal and ini files with these 2 microsteps settings (that I believe should be 16)

I would appreciate any help in trying to understand where my mistakes are.
Thank you
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20 Apr 2023 20:11 #269505 by tommylight
Your config is set for 1/2 microstepping, so if the dimensions are OK, check the drives, they are not set at 16 microstepping for sure.

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20 Apr 2023 21:24 #269519 by felucho
Thank you for your reply.
I set the drives by the documentation I got with the MD430 drives. For 16 microsteps I set S3=0 and S4 =1.

I now reversed them S3=1 and S4=0 and put back the microstepping to 16 in stepconfig and it works!!!
Lessons learned : Do not trust the documentation.
I am wondering what I have setup in the other switches...

I am now ready to move to the following steps. I am sure I will come back with more questions.
Thanks a lot for your help.
The following user(s) said Thank You: tommylight

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02 May 2023 11:09 #270473 by Geosec

felucho post=269519 userid=34852Thank you for your reply.
I set the drives by the documentation I got with the MD430 drives. For 16 microsteps I set S3=0 and S4 =1.

I now reversed them S3=1 and S4=0 and put back the microstepping to 16 in stepconfig and it works!!!
Lessons learned : Do not trust the documentation.
I am wondering what I have setup in the other switches...

I am now ready to move to the following steps. I am sure I will come back with more questions.
Thanks a lot for your help.

Your documentation does seem suspicious. Looking at MD430 stepper driver documentation SW3 and SW4 seem to be for adjusting the current (Amps). SW7 & SW8 would be for 1600 microstepping.
Of course this is just based on the generic MD430 model number.

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02 May 2023 17:46 #270496 by felucho

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Thank you for your response. I am attaching a page from my docs. The switches are labeled SW1 thru SW3 and S1 thru S6.
This is probably a clone where they changed the switch functions. I reversed S3 and S4.
Can you point me to the docs you are using?
Thanks again 
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02 May 2023 19:42 #270503 by Geosec
Your driver is no doubt different so what I was looking at wouldn't matter.

Different MD430 Doc

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26 Dec 2023 03:40 #289062 by tommylight

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