3D printing, more lessons learned the hard way

Posted in Hobbies, Journey

The first set of controller boards were replaced gratis. I can’t quite remember why anymore, it is even possible that the failure wasn’t due to my error – yes, I think I’ll stick with that.

This third set just got fried because, even though I thought I was being meticulous about having the power off before removing and changing drivers and connections I managed to have the power on and goof up. I pulled the board right way but something’s still wrong. Then I was also trying to work with some bad drivers and that can cause weird, really weird problems.

It wasn’t clear I fried the controller boards (still isn’t actually) because when I screwed up putting in the driver I had my finger on it, felt it getting hot and flicked it out in a tiny fraction of a second.

I started with almost nothing connected and found that the controller  was recognized on USB. But it turned out that none of the steppers would do anything but hum. I carefully tried all three (really carefully) and tried more than one driver board, eventually having several wired in. The controller was functional but the steppers weren’t going so that was that for the time being.

There were several choices:

  • Try over with the same and fresh drivers ($30) – seemed like good money after bad. I’d have all the same risks and it would be easy to have the same failures.
  • Try a smoothieboard solution (around $50) – seemed ok, but none of the ones I could find on Amazon had many reviews, and NewEgg wasn’t much help either. Plus, blowing one driver would render the board useless since they are soldered in place in the ones I found.
  • Try a duet board – too expensive at > $120
  • Try a MKS board which has the arduino and RAMPs integrated and has the drivers arranged better (looks like it would be harder to screw up).

I decided to try the MKS board ($37) with stepstick drivers ($14). The drivers are supposed to be somewhat protected against problem conditions and the board should be easier to deal with as a single board solution. The drivers also have more current capacity.

The  connectors for the cables also won’t allow the cables to go on wrong (backward yes, which is still a problem). Actually they won’t allow backward if I can put the right kind of mating connector to fit the cables. I’m just not sure if I can accomplish that, and it is only worthwhile for the endstops.

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