Woodworkers, I need a cutter/rotary file

T Bredehoft

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I have a machine that uses a sanding roll to shape balsa, density 5 to 12 lbs per ft sq. I want to shape pine, density 25 to 30 lb per ft sq. The sanding rolls wear out 'way too fast.

Is there a 7/8" to 1" diameter steel cutter (two to three inches long) that would have .750 hole through it, or one I could put a .750 hole or sleeve in it? I'm picturing a wood rasp wrapped around a core. Even a perforated sleeve could be made to work.

Edit: correct typo
 
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You might be able to make something using planer knives. For the ultimate (but expensive) solution you might be able to use a spiral cutter.
 
They're out there, but not sure how easy to come by or how expensive. I've used the garden variety small ones from the hardware store and depending on the brand they work ok, if they're sharp and not clogged. Pine likes to clog with the resin, but you already know that. A brush or file card will keep your cutter clear(er).

Capture rotary rasp.JPG

Search for 'rotary rasp' and you'll get hits. I'm not sure what is around in your area that would be tempting.

-frank
 
If I remember right Home Depot sells that type of rotary rasp. I think I have one.... somewhere
 
Make a drum out of aluminum and glue 40 grit sand paper to it.
 
I imagine the pitch from the pine is gumming the sand paper. Try using Crepe Rubber and clean your sanding belts. might get you some extra miles. Its the same rubber they used in shoe soles when I was a kid. Any wood worker supply sells it. Just rub it on a running sanding belt.
Also clear pine should have less pitch or sap pockets, make sure it is well dried.

Cheers
Martin
 
I have a machine that uses a sanding roll to shape balsa, density 5 to 12 lbs per ft sq. I want to shape pine, density 25 to 30 lb per ft sq. The sanding rolls wear out 'way too fast.

Is there a 7/8" to 1" diameter steel cutter (two to three inches long) that would have .750 hole through it, or one I could put a .750 hole or sleeve in it? I'm picturing a wood rasp wrapped around a core. Even a perforated sleeve could be made to work.

Edit: correct typo

Hi,
when you say you want to "shape" pine - does it need to shape a perfect cylindrical shape or be perpendicular ?

The reason I ask is I use these on grinders and they are VERY effective at carving and shaping wood.
https://www.woodcraft.com/products/holey-galahad-see-through-disc-round-fine-green-7-8-arbor

Do a search for "King Arthur's tools" on Woodcraft or other woodworking sites.
They also make cylindrical shaped sander/shapers.

Of course you need to select a "grit" appropriate to your wood and how wet/dry it is, and clean them when they gum up.

There are also cheap alternatives out there that I have not used.
 
"King Arthur's tools"

That looks great, if I could use a hand held angle grinder. But I must have the cutter/sander mounted on the Prop Machine, to rotate the work and achieve a consistent pitch. That Diameter turning over 10,000 would be too scary to think about.
 
According to their web site, those see-through disks are rated up to 14KRPM. In all likelihood they have a large safety margin at their max but it still would be wise to put some sort of shroud around the thing.
 
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