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I sanded 1 billet of rosewood with fresh 60 grit, and it's done. What am i doing wrong?

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Hutch

Get the heck off the couch and go build a guitar!!!!

You need light fast passes. Also a sanding lubricant such as maglube helps a lot.

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Jim Watts
http://jameswattsguitars.com

Oh, almost forgot, sand across the grain not with the grain. Go at an angle if you can’t go across the grain. This is really important.

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Jim Watts
http://jameswattsguitars.com

Are you using a belt cleaner like a chunk of rubber?

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"Act your age, not your shoe size" - Prince

Too much heat by too deep of a cut is most likely. As already stated, fast light cuts, like .002 at most. OTOH some rosewood is just so oily that it is what it is and you just have to endure it.

With 60 grit, you may have an exceptionally resinous piece of rosewood. I’ve run across some that gunned up no matter what.

Dust collection and having an abundance of dust collection also serves to cool the drum and will help too. I could thickness sand OK with my 10-20 Performax with a Festool 132CFM dust extractor. When I stepped up to 1,100 CFM dust collection my sanding papers lasted much longer.

I'll add I also found that I did not have to lower the drum with every pass. Multiple passes at the same setting still removed material and did not clog things up as quickly.

Everything said above about how to avoid getting your sandpaper stock loaded up with dust and resin is true. Eventually it is going to be clogged anyway. But, you can fix it!

Yesterday I found that my 80 grit drum sander paper was just totally gummed up with resin. I took the paper strip out of it and soaked it overnight in a bucket of water and detergent. After a good session with a wire brush and then some more rinsing it looked nearly clean again. After a few hours drying on the clothes line it was back in the machine this afternoon and sanding almost good as new.

I just buy 25 yd rolls of sandpaper and cut my own and put new sandpaper on. Costs me about $2 or $3 for a 10-20. Would be a bit more for larger models. My shop time is too limited as it is so I don’t mind the expense.

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Steve Smith
"Music is what feelings sound like"

I use 36 grit to within a few thousandths on oily wood and then clean up with #80 scraper. Nothing can bog the 36 grit down, not even cocobolo. 80 grit for non-resinous woods like spruce and mahogany.

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Stay with the happy people.
--Reynolds Large

As far as technique...I use a handplane to limit the number of passes in the sander. To deal with the deposit I mix a strong solution of Simple Green/Krudkutter and water and soak overnight. Scrub the gradue off with a stiff brush and rinse.

That really helps? I'll give that a try after I clean the belt.

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Hutch

Get the heck off the couch and go build a guitar!!!!

The guys at LMII used to spray silicone on their sanding belts when thickness sanding resinous woods.I have a 12" Delta thickness planer that I use to get the backs down to about 2.75 mm, then I join the pieces and go to the drum sander. For sides I take down to within a few thou. and then finish with a scraper. Saves a lot of time over just thickness sanding.

After cleaning the belt, i proceeded to run the boards at angles and ran the boards without changing the depth a couple of times. This worked fabulously. Thank you.

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_________________
Hutch

Get the heck off the couch and go build a guitar!!!!

I am a bit surprised by the suggestions of some lubricants, especially silicone based. Seems like a bad idea? Thoughts?

For me, the oilier the wood, the lower the grit. I use 30 grit on coco and black woods. Light cuts as well to avoid deep gouges. Only on one side. Then 60-80 grit to get rid of any grit lines using mineral spirits as a lubricant. Wear ear protection, its surprisingly loud! Down side is the high cost of such paper, but that is offset buy the very long life of it.

Finally, a trick I learned here is to spray gummed paper with easy off. Turns oils to "soap" and just rinse away. Make sure you weigh the ends down to avoid it curling up and leave till dry.

It is absolutely a bad idea. It can cause craters and fish eyes in acrylic finishes. Im not sure about ither finishes.

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_________________
Hutch

Get the heck off the couch and go build a guitar!!!!

I know LMI used it for years because of the amount of wood they processed. I always wipe down my wood with naphtha when I get, so It's not a big deal. Personally, I use a creperubber block for my 19-38 SuperMax. I have a Delta 12" thickness planer that I use to start with and then finish up on the drum-sander.

I have the same drum sander and I didn't find the rubber to be much good for this burned on oily wood.

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Hutch

Get the heck off the couch and go build a guitar!!!!

I had the very same problem when I first got my sander. After gunking up 2 or 3 belts (sometimes I'm a slow learner) I found I was trying to take off too much too fast. When I switched to fast, lighter passes, I had far less problems. I check the belt often and use the crepe-rubber when the belt starts getting loaded with sanding dust, before there is burning resin. When I realized how impatient I was, I began using my Delta 12" thickness planer first. The Delta takes down the thickness faster than the SuperMax, but still has its limits. I then finish on the drum-sander. Sometimes I think I need a full sized planer with a 5HP motor, lol.

I use handplanes to get close. Next time, im going to try my electric hand plane. EIR is hard.

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_________________
Hutch

Get the heck off the couch and go build a guitar!!!!

My way of dealing with the problem:

1. As many have said, take very light passes, and set the feed rate at the highest level.
2. Clean it with a rubber stick every so often.
3. Treat sandpaper (even this kind of sandpaper) as a consumable item. Buy enough of it (I buy bulk rolls and cut it myself) so that you always have a new one when you need it.
4. Become adept at switching out the paper, so that doing it is not a big hassle.

Like Steve said above, I would rather buy more sandpaper than spend a lot of my time trying to clean sandpaper. The most expensive thing I put into the instruments I make is my time.

I do have a roll and can make a few more before I run out. Learning to run the boards at an angle and only taking a few thou at a time with some repat passes proves to be saving me paper. I hate throwing it away just because it has one line of gunk so I clean it when that happens. It just takes a minute with a wire brush and some 409 that I had on hand. Maybe now that I'm not gunking up my paper, the rubber eraser will work better. At least, that's my hope going forward.

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Hutch

Get the heck off the couch and go build a guitar!!!!

Has anyone used the screen type like abranet. Not screen but the cubitron I think it's 3m

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Mike McNerney