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Jeff Higgins Jeff Higgins is online now
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Join Date: Mar 2004
Location: Higgs Field
Posts: 22,810
Quote:
Originally Posted by milt View Post
I want to cast a solid object the size of a tennis ball that has some weight to it. I will need to machine the raw casting. I can't find any links to either the process or the supplies. Preferably the end product would polish and be black.

It needs to have a decent Rockwell similar to light to medium weight metals. If that's too vague, I have seen some similar products done in brass and AL for the difference in weight vs. mass.

Not much done in composite. Maybe there's a reason?
Sounds like a pool ball. Ask Paul.

There are a good number of castable resins out there with all sorts of properties. As a general rule of thumb, the harder they get the more brittle they get. The harder they get, the better they will finish.

Any introduction of another material - to make it a "composite" will both increase strength and mess with the surface finish. We use milled glass fiber, powdered metals, and other materials, depending on what we are after. Surface finish is never high on our list with these added materials. The problems arise when you machine them, and keep exposing the "dry" centers of whatever material that may be; it finishes different than the surrounding resin.

Another option to casting your own blank is to simply buy a solid material with the properties you are looking for. If you are going to finish machine anyway, buy a chunk of "plastic" and whittle away. You would be astounded at just what is available today.

So, whatcha up to?
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Jeff
'72 911T 3.0 MFI
'93 Ducati 900 Super Sport
"God invented whiskey so the Irish wouldn't rule the world"
Old 05-06-2011, 01:09 PM
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