Made a rosette cutter while waiting for glue to dry on my soundboards.
I had made a prototype out of rosewood scraps, but cracked a piece when tightening down the blade, so I made a new one out of aluminum. Used some bar stock and steel rods. Just used my drill press, a hack saw, files, and taps and dies.
The blade was a quick HSS one from the reciprocating hack saw blade I’ve been using. Worked ok, but I’ll make a new one from W1 tool steel, a bit thicker, which I can sharpen to a much better edge. I set the diameters with a caliper, either adding or subtracting the radius of the pin (.125”) depending on which side of the blade and cutter I measured to.
Tested out on a thin redwood scrap and it worked fairly well. The outer ring I cut in both directions causing a bit of tear out. The inner ring I just rotated one direction and it was much cleaner. Then just a bit of chisel practice. I think this will work well with a nicer blade with different cutting bevel geometry. Trial and error so far.
If I only had a little milling machine at home….