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matt_r
06-23-2005, 11:48 AM
Greetings,
I am looking at a job to cut some parts out of 3/4" pine. The outline detal requires that I use an 1/8" bit. In my trial runs, I have achieved decent surface finish, but not great. The bit I am using is a constant 1/8", both cutter and shank- it is actually a metal working endmill. I am using a sleeve in a 1/4" collet. I am cutting the pieces at .03 larger than the outline, then going back with a full depth pass on the outline. I have tried both conventionl and climbing milling.

Any thoughts on a achieving a better surface finish?

Thanks,
Matt

paco
06-23-2005, 12:02 PM
I Matt!

I prefer to use straight edges carbide tipped router bit (2 flutes) for tender material like pine... easily available and cheap.

matt_r
06-23-2005, 01:09 PM
Paco,
I would like to try a bit like that, but I can't find one with a long enough cutter. Most are only .5 inches total cutter depth, and I need at least .750 deep to get through the pine. Do you buy from somewhere online?

Thanks,
Matt

paco
06-23-2005, 01:48 PM
Matt,

OKayy... I see... actually I limited myself to 9/16" CEL with "standard" router bits... let me see... got one; from Hartlauer Bits (http://www.hartlauer-bits.com), 61-140h (1/8" CED, 13/16" CEL, 1/4"Shk, 2" OAL, Solid Carb., 1 flutes, 28.00$usd). Be carefull with that lenght not to snap it (that's actually a foam bit); slow to med RPM and NOT TO FAST the feed... You might want to give a try first with a shorter one (more available and cheaper) to see if it suit your finishing needs.

Brady Watson
06-23-2005, 04:22 PM
I stock XL Long 1/8" dia, 1/8" shank 1" LOC, 3" OAL solid micrograin carbide upcut spirals @ $17ea + $4 shipping. If you order 5 or more I offer a discount, plus free 3-day shipping in the 50 states.

When cutting the outside profile in wood, always use Conventional cut. Be sure to leave .015 allowance on your part while stepping down during the 1st profile pass & only go 90% of the total depth ~ leave a skin. Then profile cut the entire piece SLOWLY to avoid deflection @ full depth with no allowance.

-Brady

bleeth
06-23-2005, 06:38 PM
Matt: Often it finishes nicer if you can work out a roughing toolpath and finish up with an 1/8" ball nose. I like a stepover of .01 max and will sometimes use .006 for very minimal sanding with the 1/8.
I usually rough with 1/4"

Dave