[Deltic_Engine]

Hi,
We're prototyping some 2" deep foam inserts (6# Polyethylene Bun Foam).
We have a 7,000 rpm Haas VF2 and have experimented with various cutters
including router bits and Burrs.

The Burrs work best (best speed and edge quality) however we cannot
find a source for an extra-long shank burr needed for this 2" foam.

Production deep-foam cutting is done with gantry mills but we've never seen
what cutters they are using or sources. There really does not seem to be
much on the web beyond a 2" shank unless it is custom-made.

Because of the geometry we can't use anything larger than 1/4" dia.

Http://www.GizzMoVest.com

[alan_3301]

check this website out, Foam Cutting Tools | Foam Router Bits | FROGTools

click orange box on the right "download product details pdf"

nothing with a 1/4 shank, but you can get a 1/4 ball mill with a 3/8 shank that has a 4" cutting length

[dblox]

I used to cut lots of PE foam with regular uncoated carbide bits.
Long series Garr endmills worked very well for me, however for a full 2 inch depth you will need to take two passes in Z for finishing.

They have 1/4" endmills up to 6" long with a 1-1/2" flute.

For the particular parts I was making (75mm depth of pocket) I used a 20mm tool to rough it out and a 12mm tool for finishing. Worked like a charm.

Here are some video's of PE foam jobs I wish I still had:

[ame=http://www.youtube.com/watch?v=XcdIgTB9qSE]Milling Polyethylene Foam - Roughing - YouTube[/ame]
[ame=http://www.youtube.com/watch?v=KMqaD1Bd1Bs]Milling Polyethylene Foam - Finish - YouTube[/ame]
[ame=http://www.youtube.com/watch?v=nYVPXUiux-Y]Routing polyethylene foam with Dolphin CAM - YouTube[/ame]