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Do any of you have some tips or tricks for drum sanding Cocobolo so that you don't wind up with this?

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

Personally I use a hand plane to bring the wood down to a rough thickness than a couple of passes trough the drum sander. It saves me time and sandpaper

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This was 120 grit & my feed was pretty slow.

Thanks for the quick replies!

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

I had issues drum sanding Madagascar Rosewood, using 80 grit at slow rate... it worked, but still clogged. I bought some 60 grit, and going to try that for Rosewoods.

Glenn

I don't have anything to add, except another +1 for lighter passes and higher feed rate. I think 60 grit is a little too aggressive, particularly with new paper.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

I use 36 grit on any oily wood that is prone to gum up paper, even EIR. Taking the belt off and cleaning with oven cleaner is not a viable option for me. I take the wood down to about .5mm-.7mm over with 36 grit and then a few passes with a sharp #80 cabinet scraper takes the coarse scratches out and takes the wood to final thickness.

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Stay with the happy people.
--Reynolds Large

I have a cheaper roll of 60 and 80 grit for these oily/waxy woods. When it loads up I soak it in a bucket of Simple Green for a few days then spray it off with a hose and it's usually like new again.

I have to agree with that speculation, based on my rather limited experience. I've only thicknessed a dozen or so B&S sets.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

Final light passes on the 38in woodmaster with 80 grit , The bulk with coarse 60 grit green abrasive from red hill abrasives on 16-32 coarse enough that with light passes does not load up saves time and my back from planing. Oven cleaner is best used on BS blades , as when tried on the 38in woodmaster it left a large ugly stain on the rubber drive belt, plus it takes a lot of brushing with a brass brush to get the oily rosewoods and bloodwood from the sanding roll .Takes way too long.High angle plane (LN 62 with 40 deg blade)and scraper when I/m energetic. and then a vy light pass through on the woodmaster

Nothing finer than 80 grit, and as has been said, very, very light passes and at the fastest feed rate possible. Going too slow leaves the abrasive in contact with the wood too long, heating it up.

Also, if you have the width, run the back through completely sideways. You'll be amazed both at how quickly it cuts, and how little heat/gumming you'll get. This goes for all woods, even spruce. If you can't run it sideways, run it through at the most acute angle possible.

Yo grumpy, thanks for the angled tip.Think I saw the same advice on robbie o/briens youtube vids on sanding wood on a larger drum sander excellent idea. I use the 60 grit as my stock is usually way oversized the target finished thickness. i.e. I will often be starting with my back plates at 5mm and perhaps an uneven cut off the BS, those get sanded to abt 3.75mm, and then down to 3mm to get the big 60grit sanding scratches sanded out on the 80 grit woodmaster. Then a quick swipe with a very sharp low angle smoother and then 180-220 -320 for final sanding

Ok, I'm going to hijack my own thread a little.

I have 120 grit on my machine because of the deep scratches I get with 80 grit. Yes, Cocobolo and other very hard woods scrape beautifully, but what about medium woods like Walnut and Maple, how do you get the scratches out? Random orbit sanding is pure drudgery IMO.

Thanks for the replies.
Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

I think a sharp scraper and the resulting surface finish is worth any extra effort.

Ryobi WDS 1600 (16-32 clone)
60 grit paper, highest feed rate, angled stock.
I never use anything but 60 grit on my sander. I don't mind scraping after that.

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John

Coarse paper, light touch and fast feed. It will still load but you'll get throught it ok.

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Joe Beaver
Maker of Sawdust

I use to keep 120 on the drum sander thinking that was the way to go. I switched to 80 and wondered why I didn't switch earlier. On gummy wood I like to take light passes and pause between passes to prevent it from getting to hot. I let it cool off....

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Guitars, guitars and more guitars.

I have this issue with ebony and rosewoods quite a but. In addition to the other recommendations I run the boards through at a 45 degree angle while thicknessing, especially because don't have an oscillating sander and it helps keep the heat down.

I sand everything at 80 grit, then bend sides, brace tops and backs, put bodies together .. getting rid of the thickness sander marks occurs as I flatten the sides prior to routing binding ledges, using a scraper, or scrape binding level on tops and backs again using a scraper, then some ROS.

On my Gen Int'l sander I use the 4.5 wide 80 grit Klingspor stearated velcro backed paper from Stockroom Supply here in Canada (however it isn't attached with Velcro .. I tape one end, the other goes into the spring clip) .. I can sand a lot of cocobolo without it ever clogging up .. best paper I have ever used ... none of the cloth backed outperform this stuff, at least I haven't seen any yet.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

I've used only 80 grit on my drum sander, and use the random obital with 120 and 220 to remove scratches. Coco was a pain on the few pieces I've tried (mostly bindings and head plates) and I'll consider going to 60 grit when I get ready to do Coco back and sides. Haven't tried oven cleaner, sound promising.

My first b&s set of cocobolo needed quite a bit of reducing, and I've always had the same problem with loading up my sander belts. So...I used my trusty Wagner Safe-t-Planer on my drill press and brought it down close to final thickness quickly, and then ran it through my drum sander a couple of times and finalized it with a scraper to achieve the final smoothing. Stunning results and combined with a Carpathian Spruce top it made the best sounding guitar I've ever done.

I did wear long sleeves and rubber gloves to keep cocobolo dust off my skin, but had no bad reaction. I like this wood so much I bought three more sets recently.

I have two belt sanders; one with 80 grit and the other with 150. Stuff like Cocobolo practically begs for the 80. Don't forget heavy protection with that stuff. It "sneaks up on you".

Like the other guys said, light passes, fast feed rate, coarse paper. If your still loading the paper, try lightly wetting the surface of the wood with mineral spirits before each pass.

And no, it won't start a fire in your sander as one fella asked me once. If you are generating sparks or enough heat to ignite mineral spirits, you've got a lot of other problems with your equipment.