<p>What do you mean by "4 ball casters "`?</p><p>608ZZ ball bearings?</p>

Thanks owen, that should work. Cura ignores very small features by default, so it may be a little tricky. I don't remember the thickness but it was a low quality print. It was probably 0.8 or 1.2 mm.

<quote>The weakest point of this design is the shaft of the side gears. It would be nice if I could set the fill density of only these parts to 100%.</quote> Hi sinan If you want to make an area solid you can put a void or more in you model there. If you put a 0.1mm hole inside your model and you have 1.2mm skins set in Cura you will get a 2.5mm column of solid plastic there (the hole in the middle is so small it will virtually get filled) If you put these holes close enough together they will all join up. You can check in Cura first. You also need to tell users what skin thickness to print at in your instructions.

I just wanted to edit it later, thanks :) This thing makes a relatively slow rotating motion (about 100-300 rpm ) and the orbit radius is 1 cm. If the radius is reduced and a higher rpm motor is used, the same design could be used for vibration generation. Maybe the side gears should be smaller too.

Cool! By the way, right now the design isn't published yet. So only us YM Admins are able to see it. Perhaps you forgot? It's not very clear, but we will make this process more clear a.s.a.p.! By the way, someone should print it and strap this to it: http://www.thingiverse.com/make:3332