The Dremel with the chuck attachment is probably my most used tool. Or I should say was. Mine went belly up today so I thought I'd take a look at the brushes. I rotated the brush holder barrel around and a brush and spring shot out and hit somewhere in my kitchen. No luck finding it. Use care when changing brushes in that Dremel! The bad news is my tool is so old parts are not available I think. The Dremel is great for drilling the holes in the beams when mounting an engine.