1 (edited by driggers 2016-01-29 13:19:30)

Topic: Skewed XY-axis (lawsy carriages). Firmware fix?

I wondered about this skew for 2 years and finally figured out why squares don't come out square.  When I installed Lawsy's replacement carriages I ended up with a slight skew (not because of inherent problems with the carriages, but something about how I printed them, or stuck the rods in).  That is, my X and Y axes are not 90 degrees to each other!

Is there a firmware fix for this?  Any suggestions other than printing new carriages, getting new rods, and reinstalling?

(there is also a Z-shift in this print, but that's a problem for another day)

http://i.imgur.com/NHqOVwF.jpg

http://i.imgur.com/j1YsRcs.jpg

SD2 Sanguinololu 1.3a atmega1284p, wood platform, lawsy's carriages, braided fishing line, pallet wood overhead spool mount, carboard/magnet enclosure, glass bed, E3D v6, bed levelling knobs, extended z-stop, 25A DC-DC SSR for bed heater, everything fixed to the SD2 frame, marlin firmware with some adjustments and extra failsafes enabled.  I'll never give up on you, little printer that could(n't)!

2

Re: Skewed XY-axis (lawsy carriages). Firmware fix?

I have learnt that there is a name for the firmware/software fix: orthogonal axis compensation.

Does marlin or repetier have this?

SD2 Sanguinololu 1.3a atmega1284p, wood platform, lawsy's carriages, braided fishing line, pallet wood overhead spool mount, carboard/magnet enclosure, glass bed, E3D v6, bed levelling knobs, extended z-stop, 25A DC-DC SSR for bed heater, everything fixed to the SD2 frame, marlin firmware with some adjustments and extra failsafes enabled.  I'll never give up on you, little printer that could(n't)!

3

Re: Skewed XY-axis (lawsy carriages). Firmware fix?

The general rule of thumb is to fix it at the hardware. Firmware fixes are a last resort effort.

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Re: Skewed XY-axis (lawsy carriages). Firmware fix?

jagowilson wrote:

The general rule of thumb is to fix it at the hardware. Firmware fixes are a last resort effort.

Yeah... actually I've found a whole lot of play in it, so better hold off on advice until I just tighten things up big_smile

SD2 Sanguinololu 1.3a atmega1284p, wood platform, lawsy's carriages, braided fishing line, pallet wood overhead spool mount, carboard/magnet enclosure, glass bed, E3D v6, bed levelling knobs, extended z-stop, 25A DC-DC SSR for bed heater, everything fixed to the SD2 frame, marlin firmware with some adjustments and extra failsafes enabled.  I'll never give up on you, little printer that could(n't)!

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Re: Skewed XY-axis (lawsy carriages). Firmware fix?

I have 2 3d printers and every thing works heating, melting, and the plate heats, but as it get's to the point to start printing it goes to the home corner and stops and starts making a loud noise, if I leave it the noise stops and the head tries to go to the start point but doesn't get there it starts to zig zag and just move around a little at which time I stop it. I have tried every thing I know to get it to work but even my other printer is doing the same thing????? Any help ????? Thanks Ron.