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View Full Version : Looking for spindle recommendation for carving foams



creaturemaker
03-26-2012, 06:42 PM
I am looking for recommendations for a spindle purchase. We are predominantly interested in milling urethane and eva foams.

It was suggested that urethane foams can be milled at approximately 8000 rpm and eva foam can be milled at 24000 rpm. Any suggestions?

This is for a 5 axis machine if it matters.

awerby
03-27-2012, 04:47 PM
Rigid urethane foams are no problem to mill - spindle speeds vary according to the size of the tool, but at least with the lighter types it doesn't really matter too much. The main problem with them is the horrible clinging dust particles that stick to everything. This is less of an issue with the higher-density urethane foams meant for milling, like Renshape, which make shavings rather than powder.

But EVA foam is a different matter. It's flexible (at least the kind I know about is) and I doubt it would be easy -or even possible - to cut it cleanly. But maybe someone here has had some success with it - one never knows...

Andrew Werby
ComputerSculpture.com — Home Page for Discount Hardware & Software (http://www.computersculpture.com)

creaturemaker
03-27-2012, 11:03 PM
Andrew, I feel like we run in the same circles. I have researched eva foam millling and people have successfully milled it at 24000 rpm for custom wheelchair cushions. I think the flexibility you mentioned is handled by the very fast rpm and slow feed rate.

I am looking for spindles that can handle those issues that are reasonable in price. Do you have any recommendations?

Lino

neilw20
03-27-2012, 11:12 PM
Ever thought of freezing the foam so it is a solid.
Not sure how low temp needs to be, but liquid nitrogen is not expensive.

creaturemaker
03-28-2012, 02:29 PM
Impractical for large blocks

awerby
03-28-2012, 04:08 PM
[QUOTE=creaturemaker;1090684]Andrew, I feel like we run in the same circles. I have researched eva foam millling and people have successfully milled it at 24000 rpm for custom wheelchair cushions. I think the flexibility you mentioned is handled by the very fast rpm and slow feed rate.

[I suppose that's possible; extremely sharp tools would probably help too.]

I am looking for spindles that can handle those issues that are reasonable in price. Do you have any recommendations?

[I've had pretty good luck with Perske's 3-phase spindles, used with a Hitachi VFD. They aren't cheap, but they do a good job and they're fairly quiet, compared with the hand routers most hobbyists start out with. Here's a link:
CRP Perske (http://www.crpperske.com/) Another good brand is Colombo; I've got one of those as well, and I've been happy with it (plus it takes inexpensive ER collets): Columbo Spindles (http://store.blurrycustoms.com/SearchResults.asp?Cat=82) . If those are out of your price range, your best bet probably is one of those Chinese air or water-cooled spindles I've been hearing about here (but haven't actually tried.) People generally seem pleased with them, if not with the cheap VFDs they are usually sold with.]

Andrew Werby
ComputerSculpture.com — Home Page for Discount Hardware & Software (http://www.computersculpture.com)

KOC62
03-28-2012, 04:15 PM
I would use a Super-PID and router.
Many routers can do 25,000 to 30,000 RPM.

The Super-PID can control the router speed from 5,000 to 30,000 RPM. This of course assumes that the router can do 30,000 RPM since the Super-PID can't make a router go faster than its native maximum RPM.