A question on milling spokes on a flywheel.

[starr256]

This is probably one of those questions that is only answered via experience. In any case, I will see what advice I get here. When cutting wood, you want to support both pieces. Got it. With vertical metal bandsaw, this is true. But with a horizontal saw, the smaller piece is not supported. OK, no problem. I am milling out the spokes of a 6" flywheel. The flywheel is cast iron and the webbing is 0.300 thick. I am just milling the outlines of the spokes, not removing all of the material. There is no support for the material between spokes. I have the top arc and one spoke done. Looking at it now, I am wondering if I should provide sort of support for the to be cut out? I am making repeated plugs cuts of 0.020" on each leg, completing each leg. The chunk to be removed is still pretty hefty. Something tells me it will chatter and be a problem as I get closer to cutting through. If this were a wood piece, I would just remove all the material, layer at a time. Thoughts from the experienced ones, please.

 

[Flyinfool]

Sometimes with a part like that I will cut most of the way thru and then on the final break thru pass I will leave several tabs connected to hold the dropout. It is easy to then knock it out and dress up the tabs. A chunk that heavy can move and bind the cutter, breaking it, or be grabbed by the cutter and turned into a missile.

 

[Mitch Alsup]

Milling out the spokes of a flywheel sounds like a job for the rotary table and some spacers to keep the RT from seeing the sharp end of an end mill.
But you only do this after the FW had been run true diametrically on the lathe, so you have machined surfaces to clamp onto on the RT.

I think I would machine a MT2 center so it fit the center of FW to minimize setup while mounting FW to RT.