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gluing cocobolo
http://w-ww.luthiersforum.com/forum/viewtopic.php?f=10101&t=16598		 Page 1 of 1
Author:  Steve Brown [ Wed Mar 26, 2008 9:37 pm ]
Post subject:  gluing cocobolo
What solvent would you use to get the oil out of this wood to allow a good bond with LMI instrument glue. Last time I used epoxy and I hated it - what a pain!
Author:  Ricardo [ Wed Mar 26, 2008 10:02 pm ]
Post subject:  Re: gluing cocobolo
Steve, I'm not sure I'd bother with the solvent. I'm working on a cocobolo instrument right now. I cleaned the back plates with acetone before joining and I still had a partial joint failure - quickly fixed with CA. The rest of my gluing (using Titebond Original) has gone OK without using any solvent - just make sure the surfaces to be joined are fresh.
Author:  Jeremy Douglas [ Wed Mar 26, 2008 10:12 pm ]
Post subject:  Re: gluing cocobolo
Someone told me to use naptha before gluing but I have done it yet so I can't really comment.
Author:  jmanter [ Wed Mar 26, 2008 10:22 pm ]
Post subject:  Re: gluing cocobolo
If you're using coco for bindings, be sure to scrape them after bending. The oils like to come out of the wood and harden on the surface. just run a scraper over it.
- Justin
Author:  j.Brown [ Thu Mar 27, 2008 12:16 am ]
Post subject:  Re: gluing cocobolo
jmanter wrote:
If you're using coco for bindings, be sure to scrape them after bending. The oils like to come out of the wood and harden on the surface. just run a scraper over it.
- Justin

Ditto. I haven't found that the solvents are necessary. I just completed one with a cocobolo body and one with coco bindings. I used both fish glue and titebond on them after either sanding or scraping and had great success on both.
Author:  LanceK [ Thu Mar 27, 2008 7:32 am ]
Post subject:  Re: gluing cocobolo
For some unknown reason, most of the guitars that I have made over the last three years have been with cocobolo
back and sides, not all but most.
I have used epoxy for all of them with 100% success rate, no joint failure (KNOCK ON WOOD).!! ;)

I don't wipe the joint either, just plane or sand (which ever you prefer) and glue up.

Why don't you like epoxy for (this) joint? Its so simple, and sands off in to a fine powder once cured.

One last comment, for rosewoods, I wont use anything but. IMHO its the most trustworthy.
Author:  Brock Poling [ Thu Mar 27, 2008 7:45 am ]
Post subject:  Re: gluing cocobolo
Epoxy for me too. I don't wipe the joints. Just joint it and glue.
Author:  RaymundH [ Thu Mar 27, 2008 8:05 am ]
Post subject:  Re: gluing cocobolo
In regards to epoxy and oily woods, which brand of expoxy do you find is the most effective?
I'm binding my Koa build with Ziricote and noticed a large amount of oil baked on the outside surface when they came out of the bender. I plan on hitting them with acetone and a quick sand before installation.

Thanks,

Ray
Author:  Laurent Brondel [ Thu Mar 27, 2008 8:33 am ]
Post subject:  Re: gluing cocobolo
IME no solvent is necessary with oily woods. What compromises the bond are the oils coming to the surface and oxydizing, and/or a poorly fitted joint. A freshly planed/scraped/sanded surface will be fine with Titebond, epoxy, HHG etc. 2 parts hardware store epoxy works fine.
Author:  LanceK [ Thu Mar 27, 2008 8:53 am ]
Post subject:  Re: gluing cocobolo
Laurent
On two different backs I had brace ends pop using LMI white glue.
It was from two different batches also because the guitars were at least 16 months or so apart.
Since that second "pop" I have used epoxy for my back braces on cocobolo/rosewoods as well. I think there is more to it than just a poorly fitted joint.
Not arguing, just telling of my experiences.
Author:  CraigL [ Thu Mar 27, 2008 9:04 am ]
Post subject:  Re: gluing cocobolo
I have used Smith's All Wood Epoxy without problem; I have used it to join backs and attach a fingerboard, all in cocobolo. I didn't find it difficult to use or particulary painful in any way. Even though you have the hassle of mixing it and it smells a bit, I wouldn't risk using other glues. Hoping that another glue will hold really isn't worth the risk. You don't want to work for months on your latest baby only to see it pop apart.
Author:  Howard Klepper [ Thu Mar 27, 2008 10:41 am ]
Post subject:  Re: gluing cocobolo
Lance Kragenbrink wrote:
Laurent
On two different backs I had brace ends pop using LMI white glue.
It was from two different batches also because the guitars were at least 16 months or so apart.
Since that second "pop" I have used epoxy for my back braces on cocobolo/rosewoods as well. I think there is more to it than just a poorly fitted joint.
Not arguing, just telling of my experiences.


I think it has been well established here (and at MIMF, as of a couple of years ago) that joint failures with hide glue are always caused by bad technique, while joint failures with any other glue are always caused by bad glue. :shock: [I know you're not arguing, Lance.].

Why not use epoxy, just to be safe? It's time consuming, expensive, and really messy; and aliphatic resin has not failed me. I used to wipe oily rosewoods like cocobolo with acetone and use either aliphatic resin or hide glue with no problems. Now I make sure I have a fresh surface and don't wipe, mostly using Aliphatic resin, also with no problems.

Squeeze out can't weaken a glue joint, but not putting enough glue in the joint sure can.
Author:  Laurent Brondel [ Thu Mar 27, 2008 11:41 am ]
Post subject:  Re: gluing cocobolo
Lance, that bites…
I've not had problems with cocobolo so far, gluing spruce and mahogany back braces. I use Titebond and have not yet used LMI white.
I've not had issues either with gluing cocobolo bridges on spruce, and even redwood. I don't lather the glue, just spread it out evenly (that's the role of the pinky) and make sure I have enough squeeze out.
Author:  Howard Klepper [ Thu Mar 27, 2008 11:41 am ]
Post subject:  Re: gluing cocobolo
Oh, the squeeze out thing was on another thread, sorry.
Author:  R W Goodman [ Thu Mar 27, 2008 12:03 pm ]
Post subject:  Re: gluing cocobolo
Ive used Smiths All Wood Epoxy on the neck and tail blocks, Titebond on the linings and fish glue on the back braces. I didnt use any solvents on the cocobolo, just sanded or scraped. The instructions from Smiths said not to use any solvents as that would weaken the joint. Everythings holding together so far. Course its not completed yet....
Warren
Author:  LanceK [ Thu Mar 27, 2008 12:20 pm ]
Post subject:  Re: gluing cocobolo
Luckily it was before the back was glued on, so very easy to fix. But it does make me gun shy.
The Epoxy just seems so easy, especially for the center seam. For back brace squeeze out, I use a damp rag with some DA on it and the epoxy wipes right off clean. TO MUCH DA will make COCO bleed like a stuck pig though wow7-eyes
Author:  Howard Klepper [ Thu Mar 27, 2008 12:25 pm ]
Post subject:  Re: gluing cocobolo
Looking at it sideways will make coco bleed. Seems that if there is a light colored wood adjacent to it, you can always see a little bleed when finish is applied.
Author:  Steve Brown [ Thu Mar 27, 2008 8:50 pm ]
Post subject:  Re: gluing cocobolo
Thanks for all the comments and suggestions. The reason I don't like the epoxy is because I like to use a vacuum press for back bracing and the slow set just takes too long. The LMI All Wood Epoxy takes hours to set.

Steve
Author:  Mark Swanson [ Thu Mar 27, 2008 9:19 pm ]
Post subject:  Re: gluing cocobolo
I agree with Howard here (Hello, Howard!), and others too who have said that all you need to do is have a fresh surface, regular titebond and hide glue which both work fine for me.
I have heard of some failures with the LMI white glue.
Author:  Jon L. Nixon [ Thu Mar 27, 2008 9:20 pm ]
Post subject:  Re: gluing cocobolo
I have a friend who is an anthropological linguist, specializing in archaic mesoamerican languages. I don't know how it came up, but we started talking wood, and he pointed out the similiarity between an ancient Mayan phrase, "coc'ke' abola" which can be loosely translated as " may as well try to glue wax paper".

I found that interesting.
Author:  Jon L. Nixon [ Thu Mar 27, 2008 9:22 pm ]
Post subject:  Re: gluing cocobolo
laughing6-hehe
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