Deep Cutting

[chodges]

This is probably a dumb question, but how do you cut lettering out of material that is 2" thick with a 1/8" spiral bit that has a fluted area that is a lot shorter than 2"?

I need to use a 1/8" diameter bit to get tight corners.

Thanks!

[andyb]

Try the long reach bits at http://www.bitsbits.net. I haven't used them but they may work for you.

Andy B.

[Brady Watson]

1st machine the letters out with a 1/4" bit and keep your stepdown distances to about .125" per pass. Then create a profile for the 1/8" tool and keep your stepdown distance to .0625 to .125" per pass, depending on material density, to minimize bit deflection and walking. You can get a super extra long 1/8" end mill from just about anywhere with a 1" or more length of cut. The OAL should be @ 3" so you should be able to have 2.25" sticking out free & clear. Keep feed rates low...and watch for deflection. Depending on material, you might want to increase your RPM way up to reduce chipload and the possibility of deflection that way as well.

-B