Issues with cutting foam

[Festus]

I am cutting a 60 durometer EVA foam. It needs ball work done to it. The problem I have is the finish is not "clean". Very hairy still. I am going 100 ipm at 20,000rpm with a .010 step over. any and all advice is appreciated!

[Mike@Lustre]

with coolant or with out ??

[Festus]

no coolant

[duckdogers]

feed rate maybe to fast?Foam might push away from cutter  before it gets a chance to cut.What kind of cutter are you using it will need to be sharp

[Festus]

1/4" ballnose

[duckdogers]

sorry that's the only thing I can think of foam isn't the easiest to cut at the best of times

[JMahon]

How much runout?

[Festus]

sorry that's the only thing I can think of foam isn't the easiest to cut at the best of times

 

I should clarify I suppose! I can get it to cut okay...just not fast enough! I am looking for any tooling/ application advice. I thought about dipping it into liquid hydrogen to freeze it?

[Guest MTB Technical Services]

Diamond-coated carbide positive geometry tooling with a cryogenic air blast (Nitrogen).

Because of the co-polymer, you might actually be better of using a carbide burr instead of an edmill.

 

You can try flash freezing the material with liquid nitrogen but depending on the nature of the foam you may damage it.

[Mick]

Is this foam for investment casting?

 

As fast RPM as possible, and like MTB says, diamond coated positive super sharp geometry.

 

I cut a ton of that stuff when making big wax investment masters for 1metre diameter impellers for water jets on a Deckel DMU125P.

[Festus]

Is this foam for investment casting?

 

As fast RPM as possible, and like MTB says, diamond coated positive super sharp geometry.

 

I cut a ton of that stuff when making big wax investment masters for 1metre diameter impellers for water jets on a Deckel DMU125P.

 

Thanks guys...I passed the request on to my tooling guy. It is not a casting.

[Jayson Kramer]

Is this a glass filled foam. is this the foam shape used in aircraft's ? it looks like the foam I am thinking after paint.

[Festus]

no glass in it...I'm not sure of the exact composite of the foam? its a customer supplied part.

[Jayson Kramer]

I do a lot of foam cutting like this for my customer. I use 2flt high spiral carbide end mill with a high sher on them. I run them from 100 to 300 ipm at about 10,000 rpm.

[Festus]

I do a lot of foam cutting like this for my customer. I use 2flt high spiral carbide end mill with a high sher on them. I run them from 100 to 300 ipm at about 10,000 rpm.

 

this is a soft foam. Not Renboard type stuff?  that pic looks like pretty hard stuff?

[MrFish]

Know of a local company that cuts insole foam all day with great finish and feed rates but they run a 100k spindle rpm on a high speed router !