machining HDPE to high finish
 

Anyone here have experience machining HDPE?

I need some tips on how to get a (very) nice finish. The piece is a mould
for a complex profile to be made in a sugar paste, and if the surface isn't
nearly a high polish, it sticks too badly to remove the moulded item.

Rakes? Speeds? Secondary finishing methods?

There are several different tapers on the tip, and they must be maintained
to a few thou accuracy, so heat polishing isn't an option unless it can be
done in a manner that doesn't distort the shape.

Thanks,

LLoyd

machining HDPE to high finish
 

Lloyd E. Sponenburgh wrote:
Anyone here have experience machining HDPE?

I need some tips on how to get a (very) nice finish. The piece is a mould
for a complex profile to be made in a sugar paste, and if the surface isn't
nearly a high polish, it sticks too badly to remove the moulded item.

Rakes? Speeds? Secondary finishing methods?

There are several different tapers on the tip, and they must be maintained
to a few thou accuracy, so heat polishing isn't an option unless it can be
done in a manner that doesn't distort the shape.

Thanks,

LLoyd




HDPE isn't the best material for a mold for those reasons. Try Delrin.
It cuts to a fine finish and can be buffed.

machining HDPE to high finish
 

"Polymer Man" wrote

HDPE isn't the best material for a mold for those reasons. Try Delrin.
It cuts to a fine finish and can be buffed.


Agreed. Acetyls like Delrin are definitely the way to go. Just keep your
tools sharp and polished and the surface comes out wonderfully. Surface
energy of acetyls is only slightly higher than UHMW so almost nothing will
stick to it.
--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

machining HDPE to high finish
 

"Polymer Man" wrote in message
oups.com...

Lloyd E. Sponenburgh wrote:
Anyone here have experience machining HDPE?

I need some tips on how to get a (very) nice finish. The piece is a
mould
for a complex profile to be made in a sugar paste, and if the surface
isn't
nearly a high polish, it sticks too badly to remove the moulded item.

Rakes? Speeds? Secondary finishing methods?

There are several different tapers on the tip, and they must be
maintained
to a few thou accuracy, so heat polishing isn't an option unless it can
be
done in a manner that doesn't distort the shape.

Thanks,

LLoyd




HDPE isn't the best material for a mold for those reasons. Try Delrin.
It cuts to a fine finish and can be buffed.


Is delrin food safe? When I was doing plastics for a living 15 years ago,
we used Celcon(sp?) for food contact acetal.

Just a thought or two.

Mike