Help! Occasional Incorrect interpretation of Gcodes

HI All, Ok insanity is setting in now... It appears if I create a Gcode file for something simple say the 1mm Square test image, Skeinforge and pronterface show correctly the moves for the print. I can even use Skeinlayer and step through everything looks fine. When I print in this case it does the outer wall 3 times as expected and then starts to fill the base layer using diagonal strokes - all exactly as you would expect. Then for a few of these strokes rather than doing a diagonal stroke it will make a perfect triangle, effectively missing out that diagonal stroke .... grrrr, I suppose it is as if it has separated the command into an X move and Y move <- hmm this may be a key point....

This is driving me mad - tried reloading the firmware (New Huxley reprappro Sprinter on sanguinololu), checked all the axis. Even patched the Sprinter code to bring it in line with Klimet's original code and Increased the serial buffer to 256 rather than 128 (paranoid) - but then this happens even if I use the SD card :-(

Help please!

Ta Rob

That's really weird. Does it reproduce if you use Slic3r to generate the gcode?

Sounds very much like one of your end stops triggered during the move. I got a very similar effect when I enabled PID control of the heater - noise from the heater turning off and on was sometimes enough to trigger the end stop detection so that on a diagonal move the head would move just in x or y and then do the other component - making little triangles all over the place.

CeeThreeEs Wrote:
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> Sounds very much like one of your end stops
> triggered during the move. I got a very similar
> effect when I enabled PID control of the heater -
> noise from the heater turning off and on was
> sometimes enough to trigger the end stop detection
> so that on a diagonal move the head would move
> just in x or y and then do the other component -
> making little triangles all over the place.


CeeThreeEs awesome... that was the pointer I needed, added some debug in to the code and found that my X and Y end stops were triggering!!

Lesson learned don't be too neat and tidy and carefully tape the end stop wires with the motor feeds !!! DOH ! I owe you a beer

Rob