A lot of people when starting off with the Shapeoko use a cheap dremel tool for the spindle. I originally tried a cheap dremel bought from a local store, but I found that the run-out (Run-out or runout is an inaccuracy of rotating mechanical systems) was terrible. Probably about 1mm of run-out. You could clearly see the run-out when you put a tool in it and turned it on. So I checked around online for a decent motor. Came upon a cheap Skil dremel for about 30 euros from a Irish website. I thought perhaps a known brand would be of better quality then a generic Chinese clone. The Skil 1415 dremel turned out pretty good. Visibly decent run-out. Haven’t any precise way of measuring the run-out. But it seemed good, which is all i can say. One downer with most dremel’s is that they are freakin loud and I live in a small apartment block which makes this a major issue. Do not want the neighbors complaining. Maybe some sort of D.I.Y quiet brush-less spindle. That’s for another time.