How To Make Delrin Fly!

Try to use a router to remove excess material. Whee! One of my readers warned me (after I had bought the router) that it would have so much power that I might have trouble keeping the relatively small pieces of plastic from launching themselves across the workshop. No kidding. It hit the far wall of the garage, and buried itself in my raw materials stockpile--it took a while to find it. So I boxed the router and router table back up, and prepared them for return to Home Depot.

The difficulty here is that the end mill that I am using has only a 1" long cutting surface (0.5" diameter), and to trim away a 0.17" by 1.57" area requires at least two passes. There are longer end mills available, and that may be the solution--but I am trying to figure out whether it makes more sense to make two passes, trimming .17" x 1.00" on the first pass, plunge down and take away .17" by .57" on the second pass, or use an end mill with a longer cutting surface, and do it as .085" x 1.57", move in, and do another .085" x 1.57" cut. I suspect that trying to do a .17" x 1.57" cut may overload it.

It is certainly the case that the Sherline works well and accurately for this. I was experimentng with a piece of scrap Delrin. I turned the Z-axis down 10 turns--or .500" inches--and then moved across the face of it. The surface was glassy smooth--and when I measured the cut, it was .500" deep--not .501" or .499".