I have cast a lead bulb for my sail boat and I need to mill the mating surfaces smooth.

I was planning on using a jig and a router on a speed controller to slow the router down.

What speed should I try to get the router down to?

Thanks

Sam

Lead, as in what you shoot out of a shotgun? You will need coolant so it don't stick to your cutter, and even that may not work. I would use as low of RPM as you can get, and watch the cutter as i think it will load up right away and break, like when you cut aluminium without coolant. Pure lead? maybe just put it into a vise and sqush it into the shape you want. Maybe if you take your wifes iron, you can iron a smooth spot. Try that when she is not at home or wear ear plugs for safty. Normally you don't machine lead.
Good Luck,
Buck Case,
Spring Lake cnc llc

Have you tried using a wood plane? Lead is soft enough to cut with a sharp knife; it just might be possible to plane it smooth.