Max Length not Matching Actual

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camais
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Max Length not Matching Actual

Post by camais »

Hi, I've been going through calibrating my rostock max using the 4 scripts and a piece of paper. However, when bringing the end effector down at the center to adjust the x/y/z max length values, I find that the only value that gets it to just grip the paper if its all the way up to 491. Actual length is around 370mm. I have tried increasing the tension in the belts in case it was skipping without me noticing, but that didn't help.

Any help is much appreciated!
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lordbinky
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Re: Max Length not Matching Actual

Post by lordbinky »

Sounds like your steps per mm aren't correct in your firmware.
camais
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Re: Max Length not Matching Actual

Post by camais »

That's what I thought, but I am using repetier firmware. After reading through this forum, I got the impression that all I need to do is set the correct belt pitch and number of teeth on pulley. Since I am using stock parts I popped in 15 teeth and 2mm pitch into the configuration.h file and uploaded it.
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kbob
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Re: Max Length not Matching Actual

Post by kbob »

Current Rostock MAX kits ship with 20 tooth pulleys and RAMBo v1.1, which has 16x microsteps. It sounds like you have an older kit with 15 tooth pulleys. You might also have RAMBo v1.0, which has 8x microsteps.
  • 20 tooth, 16x => 80 steps/mm
  • 20 tooth, 8x => 40 steps/mm
  • 15 tooth, 16x => 106.67 steps/mm
  • 15 tooth, 8x =>53.33 steps/mm
(Hope my math is right...)
camais
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Re: Max Length not Matching Actual

Post by camais »

Yeah, so I tried both combinations of 20 tooth and 15 tooth, but if i run the G0 Z0 F3500 command, it stops about 95mm from the build plate instead of 10mm.

edit: Forgot to note that my Rambo is version 1.1b so I left it at 1/16 stepping
Polygonhell
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Re: Max Length not Matching Actual

Post by Polygonhell »

camais wrote:Yeah, so I tried both combinations of 20 tooth and 15 tooth, but if i run the G0 Z0 F3500 command, it stops about 95mm from the build plate instead of 10mm
If you ever set the steps per wrong you need to verify it's correct in both configuration.h and the EEPROM settings or disable the EEPROM when changing configuration.h
camais
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Re: Max Length not Matching Actual

Post by camais »

Yep, the EEPROM is what did it.
Thanks for the quick response!
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