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It's beautiful and I love the smell, but this has to be the most frustrating stuff to work with! AAH! I've joined the back (solidly, which is a small victory with this stuff), and now I'm onto thicknessing, but it's a very slow and painful process. I took off some of the material of the B&S with a Safe-T planer and I'm now onto running the pieces through my drum sander. I only have a 10-20, so I have to make two passes to get the entire back, and I'm having to take off very little bits with each pass. I already had one roll of 60 grit get completely loaded up and the second roll won't be lasting much longer. I still have to take over 1mm off the back and both sides too! Anyone have any secrets, tricks, or any other helpful advice for me? And if anyone could make me aware of any problems down the road I should prepare for, that would be great too.

Also, I'm thinking I should take the back down to about 2mm thickness for an OM. Thoughts?

I have ruined more sanding belts with Coco than any other wood. I hate the smell (if you can smell it, you are putting your lungs at risk), hate the rash, and frankly, I don't see the worth of it no matter how pretty it looks. I have 2 sets left and don't relish using it.
Good luck!

Cocobolo is oily and will load up your belts, no matter what. To make them last longer take light passes with the 10-20 and it shouldn't take that long. Trying to take too much with each pass results in bending the frame, unequal cut and a ruined/burnt belt.
I like to join my backs at .150" max, often much less, because I really do not enjoy standing next to the 10-20 and waiting pass after pass for something to happen.
It depends on the set and on what you're looking for tonally, I've thinned perfectly quartered cocobolo as much as .065" on an OM size guitar.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Sanding belts do not like Coco oils and getting hot. Get some oven cleaner and the belts will clean. I hang the belts outside and spray, let sit for a while and rinse off with the hose. On a real bad belt this needs to be done a couple times. I have done 3 coco sets so far and tossed only the 1st belt which I burned so bad it would not clean, I use 2 60 grit belts to do a set then clean both. I found that using finer grits will load up real quick so I get close to thickness and then smooth out with the finer grit. I am so far without allergy problems but am quite careful of the dust, and wash up will when finished. Don't rub your eyes with coco on your hands, it will irritate them.

I love the sound and look of Cocobolo so I will continue to use it at least until my supply is gone.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

A couple weeks ago, I was thickness sanding some cocobolo and changed by sandpaper on my drum sander 4 times in about 20 minutes before I tried something else. I took my air compressor hose with the blow nozzle on it and held it closely to the built up gunk on the sandpaper and blew the clogs off the paper. It lifted basically all of the gunk off the paper. I finished sanding without changing paper again. Every few passes, I just blew the build-up off. I use klingpor 80 grit paper.

How about a nicely sharpened plane?

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Build log

Spray your abrasive with a light coat of Pam cooking spray (seriously) and sand across the grain.

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Jim Watts
http://jameswattsguitars.com

Cocobolo is the reason I bought a Safety Planer!
A scraper with an aggressive hook works great.

Interesting and facetious comment.
I built my first few guitars with hand tools only, save for a drill press and a laminate trimmer.
Planing the plates was OK, if long and tedious, although I wish I had then the sharpening skills I have now. Having access to a Timesaver later on was an epiphany and greatly enhanced my building experience.
Personally I am not a power tool fanatic, quite the contrary: my mindset is to use them only when the result is better AND faster than with handtools.
However a wide drum sander will greatly save time and guarantee accuracy, it's the most often used power tool in my shop. Cocobolo is easy enough to plane (compare to say, highly flamed sugar maple), but IMHO life is too short.
EDIT: the 60grit blue "planer" rolls for the 10-20 leave a rough surface, but remove stock very fast without clogging. A few passes with 80 or 120grit afterwards clean everything up.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Actually I was serious - when something seems to fail - pick an alternative method. But I confess I have turned into a handtool and jig-minimalism fanatic, save for a hand drill for the tuner and bridge holes. I am not necesarily trying to make myself more special, but as I live in an apartment, big and noisy machinery is not viable.
Planing a set of difficult back and sides can take the best part of a day or so but I find the process and workout enjoyable. Planing African Blackwood is a nightmare however, as I need to take out the blade for resharpening every few minutes.
But what i find most tedious is chiseling out the binding channels. It feels like I spend nearly as much time there as building the entire box

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Build log

Thanks for the replies, everyone. Ya know, I did build my first guitar almost exclusively with hand tools, and while it was very rewarding and a great learning experience, it's not something I'd look forward to doing again. At this point, I'm all for using power tools as long as I can achieve equivalent or better results than I would get with hand tools.

Anyway, I've tried Fred's trick with the oven cleaner on a couple of belts. I haven't been successful in getting all of the gunk off, but it's worked well enough that they are reusable. But on the second go around, they're only good for a few more passes each. I have another set of cocobolo in store, and the set that I'm using seems much more oily than my other set. So maybe this is just an especially difficult set to work with. I've continued to sand with the grain, also, because when I tried to go across the grain, even with with very light passes, the paper loads up and the machine jams almost immediately.

Well, I just thought I'd post my progress while my belts are soaking. Only a couple more passes and the back with be done, then I'm on to the sides!

One more vote for a well sharpened plane. The again I'm one of the few that enjoy the process.....

Oh, we're not that few
Especially if the sides are straight grained, it would probably go quicker and less boring than sending them through the sander over and over and cleaning the belts anyway. Good workout too

Cocobolo is one of my favorite woods. It presents some problems but the end result is worth it too me.
I love the cinnamon smell too but don't recommend smelling it. The key to success in sanding this wood along with a few others like ziricote and bloodwood is a oscillating drum. I spent countless hours fooling with clogged sandpaper with a 22-44 performax. Finally bought a Grizzly wide belt and now a Timesaver. What a difference the oscillation makes. Maybe you can find a cabinet shop in your area that has one?

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Beautiful and unusual tone woods at a reasonable price.
http://www.rctonewoods.com/RCT_Store
The Zootman
1109 Military Rd.
Kenmore, NY 14217
(716) 874-1498

I use a Simple Green soak for about an hour, blast of 90psi air on the burned area and a brass detail brush on the stubborn areas. Really helps extend the live of the abrasive. A buddy of mine uses a pressure washer on his Timesaver belts.

Looks like I'll be trying 36 grit first to start thickness my coco set before 60/80/scraper!

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Love cocobolo !!