Cutting Rubber

[Creech]

Could someone help me out I'm trying to cut 90 durometer rubber. The geometry is OD of 1.5x .5 long step down to OD 1.375 x .5 long with 2 (.5 dia) x .5 deep flat bottom holes on it. tolerance is +/- .015. All dims in inches. I tried sharp turn tool, sharp endmills, fast, slow. Is grinding feasable? Any help would be appreciated.

 

[nbucska]

I have seen grinding, lubricated with alcohol

<nbucska@pcperipherals DOT com> subj: eng-tips
read FAQ240-1032

 

[aviat]

I got some rubber machined once and the shop froze the rubber before machining, and it worked.

 

[yurseven]

I agree with nbucska using air for coling

 

[strokersix]

If you are trying to do this with 80-90 degree rake angle tools (typical metal gutting geometry) that's your problem. You need a much smaller rake angle such as 15 degrees. You'll find that the smaller rake angle will peel off rubber just like you want it to.

 

[griffengm]

Creech,
Is this a one off or a production job?
If one off, use a high rake angle tools(check definitions in Machinery's Handbook). High rake should peel this like an apple but the higher the rake, the less the edge life.
If high production, you may want to look at having the part cast to net size.

Griffy

 

[strokersix]

Griffengm,

Thank you for correcting my rake angle zero reference!