When we do foam there usually is nothing in the way of the x or y axis.
Except the limit switches.
We do need something fast as a lot of material is removed.
Especially on something large like a 3D contoured bell housing pattern.
Many many tool paths are involved to get the smooth surface finish necessary.

Paul, I will kick in here, when doing machinable wax to make two 
stroke patterns we used approximately 20-30 inches max for
finishing. Foam will require a slightly higher  rate while 
cutting. 300 ipm is a fairly typical RAPID travel. Most machines now
list a rapid traverse of 300-600 ipm. I must admit that watching 
the cutter approach the part at 600 ipm is scary even when you
have been running the part for a while. (production) 400 ipm 
is typical to many. Bill Jepson

 
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