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This is my first expierence with the thickness sander and I have a question. Is Indian Rosewood normally a "gummy" wood? I am having to replace the paper on the sander three or four times to do one back. The paper is gumming up. I have more than enough vacuum on the machine and I am only taking a little off at a time. The machine will not let you take much, or it will blow the breaker on the motor.

If you turn the wood sideways or even at a slight angle it will gum up the sandpaper less. What grit are you using?

I'm using 180 grit. I'm only sanding half of the back in each pass to try to prevent the paper from loading up. I'm getting a black gummy substance on the paper.
Mike R.

That's the problem. I usually start with 60 grit and finsh the last passes with 100 grit.

Thanks, I just ordered some paper online. I'll wait for it to come before I continue.
Mike R.

I find that when I get to the finer grits if I reduce the depth of cut and increase the feed rate a little the belts clean up easier with the big eraser and last longer.

Tim,
I agree with that. I was trying to take the wood down to demension with the finer grit, and it was loading up. I just bought the machine and it came with 180 and 220. I guess I need to do a little research. I just ordered some heavy grit paper.
Mike R.

Don't throw those gummed belts away. They can be restored to look like new by using Easy Off Oven Cleaner, a trick for which I’m forever grateful. Thank you OFL and whom ever documented this piece of advice.

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Michael Lloyd

“I was born to ignorance, yes, and lesser poverties ...
I was born to privilege that I did not see ... I didn’t know it, but my way was paved” – John Gorka

I use 80 grit on any rosewood and run the belt at full speed.
If I can, I will run the piece cross grain.

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Lance@LuthiersForum.com

For anything particularly oily I usually run it through my thickness planer on a sled - with sharp knives. The first pass or two will tell me if I can expect any tearout - if I get any, then the drum sander is required. I've done this with cocobolo, ebony and ziricote.

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The member formerly known as erikbojerik....

WOw! Thanks for all the advice. Lance, you sand across the grain? What grit paper do you use when you do that, and why? Thanks for the tip on using EasyOff oven cleaner to clean the sandpaper. Never heard of that one, but I will try. I ordered 60 and 100 grit today, but I can use the others again to final sand. The paper is in good shape, just a lot of gummy residue in some places.
Mike R.

Erik,
That is a brave thing to do, running your sets through a planer. I have a planer that is 15 years old and I bought it new. I would never trust the planer enough to try that. Planers have a tendency to grab things and do nasty stuff to them. I have a 15" planer that works great, with sharp blades, but I would not try that. These sets cost to much to take that kind of chance. Maybe you have a much better planer than I do. I have used a sled before, but not on backs and tops. Have you had any problems doing this?
Mike R.

Mine is just a 13" Rigid from Home Depot - I have honestly never had anything kick back at me or turn into splinters, and I use it a fair bit since I am usually starting with lumber in the ruff and resawing my own backs & sides. I have no qualms about taking them down to 0.1" - from there I will go to the thickness sander.

I've never tried it on tops, they tend not to gum up the paper on me.

The only problems come with curly figure which tends to tear out, but I can tell this after the first pass. That and the occasional end snipe (time to check the infeed & outfeed tables).

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The member formerly known as erikbojerik....

Erik,
That is pretty cool. I guess if you don't try, you don't know what the result will be. I have been planning my own wood for many years. With furniture, end snipe isn't an issue. You say you are resawing? That is something I want to get into at some point. I started out buying my sets from some of the suppliers, but I would rather resaw my own. I have a 20" Meber bandsaw which is capable of resawing. How thin do you resaw to? And how much sanding does it take to get rid of the saw marks and down to a workable thickness? I can handle up to a 1" blade on my bandsaw. What kind of blade do you use? It has been my observation that you need to go slow when resawing. That builds up a lot of heat and can cause the wood to cup. Have you had that problem?
Mike R.

On oily woods you need to lubricate. Wipe the wood down before each pass with a light coat of paint thinner. This will keep the paper from clogging up. I've been doing it for many years without a problem.

On Erik's approach with the planer:

If Erik says it's working for him, then by all means he should do it.

But here's a warning to all others: If you run wood through a planer that is less than 3/8" thick, there is a real risk of destroying the wood, and sooner or later it will happen.

As we all have experienced, when wood gets thin, it has more and more of a tendency to cup or warp in some direction, and it also becomes more flexible. This combination is VERY BAD when it comes to a planer.

When you run a 1" thick board through a planer, the knives grab the top, leading edge of the board and try to pull the wood up and back (toward he back of the board). On a 1" thick board, the board has enough stiffness to resist that force, and the bottom of the board remains flat against the planer bed, allowing the knives to cut through the top of the board.

Now suppose the board is only 1/4" thick, and is therefore a little flexible. When the planer knives grab the top, leading, edge and try to pull it up and back, the board is not as stiff as the thicker board. So, the board may give in to these forces and flex upward at the leading edge. Which causes the planer knives to grab at an even lower spot on the board, pulling it up even more, causing it to flex more, and so on, until eventually the board breaks, the front few inches getting chewed up by the planer.

I saw this happen several times recently when I was taking a class at the William Ng School of woodworking. We were making 1/4" panels for a cabinet, and several people tried to get the panels to 1/4" by running it through William's 20" Felder planer (wow, you haven't used a planer until you have used one of those!!!). I don't believe there's a finer planer made today than the Felder. It's incredible. But when the wood got less than 3/8" thick, it became sufficiently flexible that every now and then it would destroy one of the panels. Many panels would be fine, but some would get totally destroyed.

I'm not saying Erik's system isn't working for Erik. I am saying that even a very high-end planer with extremely sharp knives will occasionally destroy a piece of wood that has become thin enough to flex significantly.

I've planed a fair amount of wood to 1/8" in my little Delta 12 1/2" planer. It works most of the time but occasionally I'll get a blowout, usually somewhere in the middle of the board. That's one of the reasons I bought a thickness sander.

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Steve Smith
"Music is what feelings sound like"

I thickness sand my wood also. You can't go finer than 120 grit paper,or you'll get burning,clogging,etc. I like my 18/36" Delta a LOT better than any Performax sander. Those that have heads that rise up and down are not stiff enough,and the heads flex upwards. The Delta has a fixed head,is made of 1/8" thick steel,and you can adjust the cast iron conveyor table until there isn't even .001" difference across the board. It really vacuums itself well,too.

I have noticed that the small "lunchbox" type planers will plane wood smooth that a larger planer would tear. Their high speed rotation probably helps,and the knives DO need to be sharp. I still am not advising running Brazilian rosewood through them,though! Sander is a lot safer.