question on deep cutting

[ddrumguy]

could anyone share their thoughts on speeds/feeds and bit stickout when cutting deep cuts.

I have a hypothetical situation where i am trying to understand how one would cut a reverse mold (in foam) possibly 3" deep.

which bit and feeds/speeds would be used? especially taking into account bit stickout.

same question and probably more specifically - what about using a long ballnose to do the cleanup at this kind of depth (feeds/speeds, stickout)


anyone care to chime in on this one? :D

[coryatjohn]

I have a specialty end mill from Amana for doing foam. It's got a max RPM of only 6,000 so it requires a spindle to work. These end mills cut very cleanly and make a minimum of mess. For finish, I use an extra long ball nose. It seems that for foam, 1/2" end mills work best. If you're using a super dense foam, smaller end mills would probably work without tearout.

My take on foam is big end mills, low RPM's, faster speeds (6-8 IPS) yield a good quality cut.

Foam cutting generates a lot of static electricity so be aware of that.

[ddrumguy]

I have a specialty end mill from Amana for doing foam. It's got a max RPM of only 6,000 so it requires a spindle to work. These end mills cut very cleanly and make a minimum of mess. For finish, I use an extra long ball nose. It seems that for foam, 1/2" end mills work best. If you're using a super dense foam, smaller end mills would probably work without tearout.

My take on foam is big end mills, low RPM's, faster speeds (6-8 IPS) yield a good quality cut.

Foam cutting generates a lot of static electricity so be aware of that.

Thanks much for the response! care to share what number that endmill is?

[coryatjohn]

Amana Tool HSS1214 Foam Cutting Square End 1/2 D x 6 CH x 1/2 SHK x 8 Inch Long Extended Reach CNC High Speed Steel (HSS) TiN Coated 4-Flute Spiral Up-Cut Router Bit

This one.

[ddrumguy]

Amana Tool HSS1214 Foam Cutting Square End 1/2 D x 6 CH x 1/2 SHK x 8 Inch Long Extended Reach CNC High Speed Steel (HSS) TiN Coated 4-Flute Spiral Up-Cut Router Bit

This one.

Awesome ! Thanks!