Hardwood fuzzies

[chuckster]

After cutting mostly mdf, acrylic, polycarbonate, and plywood for the past 3 years, I recently acquired a job to cut several species of natural wood. It seems Red Oak tends to leave lots of fuzzy surrface after the cut. I have been using both the 1/4" downcut spiral as well as a single edge straight bit, several passes at 1.7-2 ips. Ash, maple, and cherry don't seem to be a big issue. Any ideas?

[harryball]

Make sure you have the right bit for the job, i.e. you are not using a bit with geometry meant for plastic or soft wood on hard wood. Onsrud catalogs (available online) are a good source for info.

Try cutting in climb cut not conventional (or vice versa if you are running climb)

Try cutting large by .005 or so then run a clean up pass. I run climb cuts on my cedar bat house sides with a final conventional clean up pass which gives me clean results.

/RB

[knight_toolworks]

I cut lots of solid woods but not red oak. I use a downcut and get very clean cuts. so if the bit is sharp it may just be the wood. doing a climb cut may work but I have not tried it. I jsut cut poplar with a downcut and it was nice and clean with a regular cut but fuzzy with a climb cut.

[Gary Campbell]

Chuck...
When I get fuzzy cuts in hardwood, I switch to a single O flute conventional cut and slow down a little to keep the chipload up. The clean up pass works well also.
Gary

[mzettl]

Like Steve, I cut a lot of hardwoods, both American and foreign. Certainly there are some species that just tend to fuzz up, and sometimes two boards of the same species will act differently. One factor is the grain direction. If the rotation of the cutter is such that it wants to "pick up" the grain, the cut will be fuzzy. It's the same as when you run a board through a jointer or planer, or even plane a board with a hand plane. Run the board in one direction, the cut will be smooth, flip it end for end and it will feel fuzzy.

For this problem, it doesn't matter whether you climb cut or conventional cut, because it's the direction of cutter rotation relative to the grain direction that is the cause. I gave up a long time ago trying to solve this problem with the ShopBot. You can minimize it by taking a very light "finish pass," and that will lessen the amount of cleanup you have to do.

-Matt

[chuckster]

Thanks everyone for the excellent advice and ideas!