It's designed for very fine wore like you find in a speaker coil... if you wind heavier than 18 gauge I think it will fail. 18 may even be to much for it...
Any tips for hand winding the wire? Not sure how to "straighten" it as it unwinds. As it has a natural 'bend' in it from being wound on the reel of course.
Wasting a lot of space, and pushing it around or trying to flatten it, the wire is too strong for that.
Suppose I could always just try to wind the next layer tightly over the one before it to squish it down as much as possible.