Machining laminates with urethane interlayer

[kaizad]

Hi,

I am attempting to machining a laminate of acrylic/polycarb with an interlayer of urethane. I have machined polycarb and acrylic before but never with the interlayer. Since I have been told that machining urethane is totally different from the other plastics, I would like to know if anyone has machined urethane and also appreciate it if anyone can suggest tools and cutting parameters for the same. A high speed router will be used for the application with AIR COOLANT (no liquid coolant) owing to nature of parts and the vacuum ports in the vacuum table.
Please let me know if you need further information.

Thank you.

 

[CMfgE1]

What type of machining and operations are you looking to perform?

Milling, turning, drilling, tapping, etc.?
And what air coolant system are you using?
What kind of router bit? and size



Thanks

Quote: "Its not what you know, its who you know" - anybody trying to find a decent job

 

[ajack1]

Urethane is not very nice stuff to machine as it basically pulls away rather than cuts and also tends to “dull” tooling very quickly.

The most important thing is to use sharp cutting tools (not tungsten or the like) with a rake angle of about 25 degrees and a clearance angle of about 15 degrees. As for cutting speeds if milling or routing use a cutting speed of about 100m/min air-cooling should be fine.

Good luck, I think you might need it.

 

[griffengm]

Sounds like it might be better done with water jet.

Griffy

 

[RobWard]

Well, some urethane machines very nicely. What shore hardness is it?

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