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Hi
I am attempting to thickness sand some Camatillo which is very oily. It is gumming up the sandpaper in one pass. I am using a 16 gallon vacuum as dust removal and it has worked fine for the last three years on everything from rosewood to ebony so I don't know if that is the problem but it could be. Any thoughts appreciated.
Bob

Sounds like you have some experience....

Having said that, you could try taking lighter passes (ie: remove less material) of course. Any way to increase the air flow in your shroud is a good idea, if you can add a air line which can blow some air in there that can help cool the sandpaper down. Of course is will stir up the dust more but if you have good dust collection that should be ok.

The other thing to do is go to a courser grit, say 50 grit to remove the majority of the material, than go to 80 grit to sneek up on your final thickness, than final sand (drum sander or hand sander) with 100.

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Thanks, Coarser grit is probably my best bet. I am trying use 120 and think the space between the sanding grit particles may be too fine for this wood. I'll give a try and report back.
Bob

Ya, I would say that's your problem. 120 for material removal is to fine I think. I never have anything finer than 100 on my sander which I try to use only on softwoods, and when sanding hardwood, I usually use 80 grit and just sand with the orbital with 100 after that to get any sanding scratches out.

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Rod is right!
Use 60 or 50 grit !
The resins will still load the paper -but you can still thin the wood with them!
then go to 100 grit -then finish with a palm sander with a finer grit!

Speed is important-to slow -you load the paper-to fast and the resins get soft from the friction!!!!
So practice on scrap pieces!
Mike

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Mike Collins

Run full speed, take light passes, angle the material if possible, lots of vac. The resin seems to gum up worst when your drum gets warmer. Anything you can do to keep the heat down will help.

Rich

Thanks guys, contacted LMI, where I got the wood, and they suggested wiping the wood with acetone. This seemed to help if I wiped after each pass. Guess I'll have to get some coarser stuff.

Don't miss Rich's comment on angling the wood as well, that makes a big difference with oily wood.

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David White, Toronto

"All my favourite singers can't sing."

When roughing wood to get close to my final thickness dimensnions, I go to my 24 inch Timesaver with 80 grit paper and make a few passes to get it to about .100" for sides and .150" for backs.

I then go to my smaller Performax 16/32 that i do all of the finish sanding on. I make light passes and use 120 grit paper on this machine.

With really oily woods, i make a few (2-3) passes and change the belt. I recently sanded a tough set of Cocobolo that forced me to make a single pass an then move the sides over and make another single pass before the belt was competely packed.

It took a total of six belts for me to gt the back and sides down to their final dimensions. This isn;t the norm, but this is an extreme case.

Take light passes and watch your feed rate. Change the belts as soon as they're packed to avoid heating the wood up and burning it.

Regards,
Kevin Gallagher/Omega Guitars

Saw this the other day don't know if it helps?

http://www.anzlf.com/viewtopic.php?t=831

Also whats peoples opinions of the hand built thickness sanders where the work is fed through by hand, as I'm thinking of building one and posibbly using velcro backed abrasive as I know a cheap supplier of it.

Thanks

John

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I learn more from my mistakes than my successes

OK, I'll go off-piste here.

For all oily woods (including many rosewoods) I've gone entirely to the thickness planer. I planed down a 2x6 for sides and a 2x10 for backs, stuck 100-grit paper to them, and use them as sleds in the planer. I can easily sneak up on the thickness, all the way down to 0.08", and I've never turned anything into toothpicks (yet..).

But I keep my knives sharp and rollers clean, and take care to make sure my in/out-feed tables are nice & level.

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The member formerly known as erikbojerik....

And what about curly figured wood Eric?

Running through the planner can work and running it at a slight angle will also help, but one certainly needs to be careful when using a stationary power planner for thicknessing thin stock. The backing board helps a lot I'm sure.

John, I use a homemade drum sander but I don't use the hook and loop paper, although I've heard of some who do with good success.

The key to material removal with any thickness sander is lite passes with the proper abrasive on the sander. These are generally not ment for material removal rather for final sanding.

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I was having similar problems and called klingspore to talk about it. they suggested THIS SANDPAPER to solve the problem and I absolutely LOVE it. I doesnt load up near as bad as the red sandpaper does and outlasts the other stuff at least 5 to 1. I bought a roll of 60 grit for the rough thickness sanding and it is truely a dream to work with.

Be prepared to get off of your wallet when you buy a roll of it. It isnt cheap but will pay for its self in the long run.

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Reguards,

Ken H

That's good looking stuff Ken and compared to what I pay for sand paper rolls like that up here in canad ($125 same size roll) that's darn cheap.

I think it's time to start buying south of the boarder.

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"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

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+1 on the Klingspor blue sanding belts.I use them @80 grit on a radius sander and they last at least 4 times as long as the red resin belts.They are well worth the money.
The best part is they help to maintain a true surface as they dont load up as easily.
Angle your parts to spread the heat and resin out over a larger area.That will help you get a more consistent measurement across your part.
There is another thing to do that will remove resin from belts .Try oven cleaner ,rinse and let dry ,try sanding again.
Try reversing your abrasive to expose the other side of the grit.Some abrasives get dull on the leading edge, reversing your belt extends the life by at least 20-30% in my experience.

Best of luck, Brett

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How long is that in luthyears?

I use a belt sander but here is a valuable tip . Finer grits will creat more heat. The coarser the better. If I am doing an oil or resinous wood I will start with 36 to get a flat surface , 60 to clean up the marks from the 36 and get to within .025 of final. Then 80 to within .005 then 100 finish and take tiny cuts as the finer grit may burn or pull oil.
Koa can be a stinker for that. Hog can darken at spots. Feel the wood as you work. If the wood feels very warm your are taking too much or have too fine a grit. Never take more than .010 on 60 and 80 grit. above 80 .002 .
john hall

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John Hall
blues creek guitars
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