Nevetslleksah
Plastic
- Joined
- Jun 30, 2011
- Location
- Troy, MI USA
I have the opportunity to quote a small job which consists of (5) rectangular blocks of Black Polyurethane, 80 Shore D. The blocks are approx 2 x 2.5 x 3" with flat bottom pockets that have .50" radius. The pockets are 1.12 to 1.50" deep depending on the detail drawing. The tolerances are all plus/minus .010". Each block will also have two 3/8-16 tapped blind holes 3/4" deep. I have never machined polyurethane before. I would be using a manual Bridgeport mill with max spindle speed of 4200 rpm. Customer is supplying the material, so if I scrap any, it will be coming out of my pocket. And the customer doesn't usually supply any extra material for "practice". Any tips for cutting speeds, feeds, tooling be that high speed steel or carbide? Is liquid coolant necessary? I usually use a compressed air cooling gun for cooling. Am I going to be able to clamp this material in my milling vise? Since the radii in the pocket corners is 0.50", I would plan on using a 1" diameter end mill. I usually mill mild steel, brass, aluminum, and hard plastics. Appreciate any timely advice, as the quote is due in three days.