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AndrewKuker
09-04-2013, 01:41 PM
looks so cool- savage woods (http://savagewoods.com/product-category/inventory/exotic-wood/cocobolo/)

hawaii 50
09-04-2013, 01:53 PM
Wow Nice Andrew...

Moore Bettah Ukuleles
09-04-2013, 01:56 PM
I've bought from Savage in the past. They are a good company. It seems that most of what they have to offer is flat sawn so use care when choosing.

Dan Uke
09-04-2013, 03:10 PM
Besides the description saying it's quartersawn, how can you tell if it's flatsawn?

Moore Bettah Ukuleles
09-04-2013, 03:16 PM
Besides the description saying it's quartersawn, how can you tell if it's flatsawn?

By looking at the grain pattern.

Dan Uke
09-04-2013, 05:36 PM
By looking at the grain pattern.

I'm glad I can read grain patterns...back to the internet to do more research ;)

Chris_H
09-04-2013, 06:00 PM
the first uke body I built was from a single piece of really nice flatsawn Cocobolo veneer that I had cut 3-4 years previous, very well dried. I finished it this spring, and about a month ago noticed that a small crack had developed near the heel, running into the back about 1.5" I am guessing this is because it was flatsawn.

I will think real hard before I use a flatsawn back again, especially with a wood like Cocobolo.

Allen
09-06-2013, 09:12 PM
There are other issues besides flat or quarter sawn with Cocobolo too that people should be aware of.

It's one of those woods that people can be very sensitive to. Either initially, or after some exposure to it. I'm one where it does affect me. Difficulty in breathing etc.

As well, it can be a complete pain in the bum to get a glue to take. There can be some really stubborn oils and or resins that seem to have an anti-adhesion factor. So be warned. It's not for the in-experienced builder to start off with.

Masonguitars
09-07-2013, 07:43 AM
I am in the middle of building a Cocobolo tenor with curly western red cedar top--my first using Cocobolo. No problem so far with allergies (at least no more than with any wood), but it clogs my drum sander, and the dust and oil stains everything it comes in contact with. I've seen the warning about gluing before, so I am doing a fresh, light scrape of any Cocobolo surface right before gluing. Also shellacking the top and any other wood that might get stained by the coco dust. In spite of all this, it is soooo gorgeous.

Moore Bettah Ukuleles
09-07-2013, 07:54 AM
Glue joints have to be thoroughly scrubbed with acetone until no more color (oils & resins) appear on the rag. This has to be done within a minute of gluing otherwise the oils will migrate back to the surface. Then hope for the best.

Chris_H
09-07-2013, 10:14 AM
After soaking the ends of some boards in a pail of acetone for only a few minutes, maybe 24 ends of 1" x 3" mitres then letting the acetone evaporate, a 1mm+ layer of black tar resin was left.. amazingly resinous wood. When drilling it, often the resin will bubble up out of the wood.

I am not so quick on gluing after cleaning with acetone, but I clean it thoroughly first, more than just a quick wipe. I wipe with a wet rag until massive amounts of color is no longer coming onto the rag. Sometimes I will dip mitres to be glued, then let them dry thoroughly.

For milling, and especially sanding, really every process needs proper dust collection. Sanding with an orbital with no dust collection will fill every nearby nook and cranny with toxic dust. Get someone who is highly allergic to Cocobolo near there, and you could have a bad situation.

Still, I love Cocobolo. It is worth the effort. I love that wood.

Also, it requires a lot of patience in allowing moisture to stabilize after milling when using it. In a 2" thick board, the interior will probably hold most of it's sap moisture for a long, long time with air drying. A kiln can only go so far in drying Cocobolo without causing lot's of checking. Better be patient with that wood, with any wood really.

With drum or belt sanders, 100, maybe 120 is about as high a grit as you can go. My old wide belt sander used 48" belts. 100 grit was top with Cocobolo, and just barely too deep a cut, or too many successive passes with Cocobolo would clog the belt. My new widebelt uses 60" long belts. I can sand Cocobolo to 120 grit, and with 0.008 passes, clogging is not as much a problem anymore. With 100 grit, the 60" belts just don't really clog.

BlackBearUkes
09-07-2013, 03:21 PM
I like the stuff for binding and trim. I used most of the heavy stock I had left for some nice croquet mallet heads, hard tough stuff.

Chuck Dubman
09-12-2013, 07:24 PM
The irritant is similar to urushiol, the oil that gives poison ivy its bite. If you're sensitive to one, you'll be sensitive to the other.

JedSmith
09-23-2013, 03:11 AM
The irritant is similar to urushiol, the oil that gives poison ivy its bite. If you're sensitive to one, you'll be sensitive to the other.

Its quite common for people to be sensitive to it. A relative experienced hives and the associated itching and red blotching from contact with cocobolo. They were itching many days after initial contact, and the red spots on their skin lasted many weeks till it faded. Its one of the most toxic woods in this regard. Very oily.

Tarhead
09-23-2013, 10:56 AM
If you are not confident in your glue this stuff is an alternative for Cocobolo:
http://www.smithandcompany.org/TropicalHardwoodEpoxy/

They warn against using a solvent pre and post glueup. Evidently it uses the natural resins as a binder.

Chris_H
09-23-2013, 01:39 PM
this just arrived at my shop this morning. It is now surfaced, shellacked, some of it sliced into veneers. One of the boards cut into veneers would make some very pretty uke sets, I will probably keep at least a couple. This is really nice Cocobolo. All boards are over 6' long. The board with the spider-webbing is pretty close on dead QS.

http://farm3.staticflickr.com/2885/9906023385_e9c488e963_o.jpg (http://www.flickr.com/photos/51504257@N02/9906023385/)

http://farm4.staticflickr.com/3675/9906069666_13d40d92cb_o.jpg (http://www.flickr.com/photos/51504257@N02/9906069666/)

http://farm6.staticflickr.com/5498/9906068476_a3911b5a17_o.jpg (http://www.flickr.com/photos/51504257@N02/9906068476/)

coolkayaker1
09-23-2013, 03:41 PM
Cocobolo. There is no wood name more fun to say than cocobolo.

Except maybe bubinga.

AndrewKuker
09-24-2013, 07:22 AM
Cocobolo. There is no wood name more fun to say than cocobolo.

Except maybe bubinga.

Ha! So true. Cocobolo can be fun in that wooly bully sort of way.... but Bubinga! now that's some real kicks. Not inherently, but with the right technique...
Hey, if you and Cathy have a girl you should name her Bubinga!
Destined for fame, garans ball barans. Gotta sell the wife on that one. right?

coolkayaker1
09-27-2013, 04:39 PM
Ha! So true. Cocobolo can be fun in that wooly bully sort of way.... but Bubinga! now that's some real kicks. Not inherently, but with the right technique...
Hey, if you and Cathy have a girl you should name her Bubinga!
Destined for fame, garans ball barans. Gotta sell the wife on that one. right?

You're right, Andrew. I'll mention it to Cathy. Bubinga! Could call her "Boob" for short.