Machining Polyurithane

"jroncallo roncallo @snet.net>"

"jroncallo roncallo @snet.net>"

These people give good advice that works:

Grinding works well even on things like sponge rubbers.

But it leaves one hullova mess!

DOC

According to Harold and Susan Vordos :

Gentelmen

Thank you for all the help. From most of the posts here it kind of pointed me in the right direction. Get some tool with a high rake in there. I made a tool out of a piece of 1/2" tubing. I ground down 90 % of the cross section from one side and sharpend it to effectively make a boaring bar with a very high rake angle. I did forget to mension that the bore was not required to be precise, so eyeball round was fine.

I also liked the idea of frezzing but anything below houshold frezer temperature was unavailable (Except for the last 5 LB of Freon 12 I have)

I use a diamond ground insert (RB), too, which would be sharp enough, but sharp isn't enough for this material. If you haven't attempted to machine it, it's hard to understand. It machines much like rubber. It requires considerably more positive rake than is available from insert tooling, plus a broad, deep chip breaker (if desired), thus my comment. I have no doubt that a successful tool could be ground in carbide if one cared to spend the time.

Harold

According to Harold and Susan Vordos :

O.K. I'll take your word on that.

Enjoy, DoN.