1 Topic by michaelosully268

  • michaelosully268
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  • Registered: 2015-03-15
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Topic: Printrboard stepper current adjustment

Hi
I have gotten back to printing after figuring out how to get the Printrboard Rev f to work with the solidoodle firmware.
I am now able to print again but I have noticed that the prints are coming out in a wavy pattern. I had this problem before when I was using the standard solidoodle Rev E board and all I had to to was adjust the motor current using the dials on the board but with the Rev F version of the Printrboard they have gotten rid of them.

On the printrbot website they have this tutorial to set the current for the motors.
https://printrbot.dozuki.com/Guide/Adju … 53?lang=en
I tried this tutorial which uses the commands
M907, M909 and M910. Hoever these commands dont seem to anything when I try them on the solidoodle.
Is their another way to modify the extruder motor current?

2 Reply by grob (edited by grob 2015-12-23 01:36:24)

  • grob
  • grob
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Re: Printrboard stepper current adjustment

The solidoodle firmware is based on Marlin.

Problem is that Marlin isn't yet set up to work with the printrboard rev F digipots at all: the digipots use i2c, the chip is a MCP4728, which is a 12-bit version of the 8-bit MCP4451. While the 4451 is supported in Marlin, so you could probably get these to work with a bit of configuration, unfortunately the 4728 would require some pretty detailed work to get going as the communication is different.

I'd recommend checking in at the marlin github, maybe raising an issue, seeing if any of the boffins over there can make it happen... I'd offer, but have no way to test as I go! There are likely a few others who would like to run Marlin on the rev F printrboard.

Otherwise, maybe see if you can configure Printrbot's real firmware for the rev F board (it's a special version, different from the older boards, probably for this reason) to work with the solidoodle - there's really nothing special about the solidoodle, it works just like any other printer, so this might actually be the easiest option.

Sorry, not a trivial problem! smile

SD3. Mk2b + glass, heated enclosure, GT2 belts, direct drive y shaft, linear bearings, bowden-feed E3D v5 w/ 0.9° stepper
Smoothieboard via Octoprint on RPi

3 Reply by michaelosully268

  • michaelosully268
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Re: Printrboard stepper current adjustment

I wouldn't know a lot in terms of modifying the printrbot firmware.
Im thinking would it be possible to adjust the current using some sort of circuit between the board and the motor.
With the Rev E board you adjust it by using just a simple potentiometer. If you could attatch that between the motor and board. Would that work?