I bought an egg-bot for my 12 y.o. daughter, and she put it together almost all by herself. I supervised, but had little to actually do, other than occasionally tighten something tighter or loosen something I'd tightened, etc.

The device is awesome, and lots of fun, and working quite well now. Except for one minor detail: the drawings are generally skewed a bit, so that for instance text that should be straight comes out looking italic. Here (hopefully...) is a flickr pic of an example of such a drawing:


Egg 1 by tastewar, on Flickr

What would cause this? It doesn't look like it's slippage (to me) because it seems like the designs properly go around 100%/360 degrees and line up.

First off, it's looks like your egg *is* wobbling (or slipping or precessing) as the egg turns. You've got a stripe that should be an even circle around the egg that doesn't meet up after a full revolution.

The most common cause of this is poor coupling between the egg and the egg motor. When the egg is properly positioned, the rubber cup contacts it all the way around, and (more or less) the egg cannot be rotated with respect to the motor.

For the other issue-- the "italics," the most likely issue is again one of alignment. Check that the widest part of the egg is dead-center in front of the pen-motor shaft. Check that the pen motor position is roughly in the center of the vertical slots. Check that every part of the pen arm is rigidly screwed together, with no play (except for the hinge) and that the pen is secured in place.

I'd also suggest starting much simpler-- maybe with drawing a square or the "hello world" example file.