Machining HDPE

[Biopyro]

Does anyone have any experience machining HDPE rod?

I plan to use it to make a new piston, but don't want it if it's going to melt when I put tools to it or cause similar problems

[john bunsenburner]

HDPE shoudl keep its shape up until temperatures of 100°C(212°F). I persume that if you are using a lath, all you have to do it to turn slowly and to keep friction down, otherwise oyu should be fine.

[Gippeto]

Did you try google?

http://www.plasticsmachining.com/magazi ... -HDPE.html

Skimming through, it seems as though it should be pretty easy to work with.

[Biopyro]

Yeah I did, but it didn't mean a lot to me unfortunately. Basically - go slow and keep the tool angle fairly shallow? What does it mean by using rounded tipped tools?

[psycix]

What does it mean by using rounded tipped tools?

That your tool has a round tip? I guess that something with a really sharp point creates too much heat at that single point.

I think that you should be fine doing it do slowly and taking your time. Dont take off to much material in one go.
The slower you go, the more time for stuff to cool down.

If your HDPE rod is cheap for you, you can always experiment or just try things.

[Gippeto]

Probably not too critical. 550m/min (~1788fpm) seems awful fast, but I'm no expert.

I would have suggested 500 to 1000 fpm. (Oh well...:dontknow: )

A round nose bit is simply not sharply pointed. There is a round nose turning bit in this assortment.

http://www.finelinehair.com/home/lathe_ ... shapes.jpg

Perhaps Nova will chime in?