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I understand that cocobolo can have some issues adhering when glued. I'm considering a cocobolo fingerboard and bridge on a current build. At this point I've not been using HHG. I have been using Tightbond Transparent glue recently and have been happy with its characteristics. I'm wondering if a cocobolo fingerboard or bridge would come lose unless I take any appropriate precautions.

Any thoughts on the matter and any particular precautions I should take when gluing cocobolo?

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

I've done a couple of cocobolo fretboards, and one cocobolo guitar.
No wiping with anything, that can be counterproductive. Freshly scrapped surface, well fitting joint, and Titebond Original.

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

My last build had Cocobolo bridge & fingerboard.

The fingerboard I glued with epoxy (West Systems). The bridge I used hide glue after giving the underside a fresh scrape.

No issues after a little over a year FWIW.

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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.

my last fingerboard was also cocobolo. after some discussion, i just went along and used good old HHG. Surface was freshly scraped, it all went good - much to my astonishment.

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member of the guild of professional dilettantes

I've done many Cocobolo fretboards and bridges and concur that fresh scraping and Titebond is perfectly fine.

I've never had issues with Tite Bond and coco. Just rough up surfaces and go. You can always wipe glue area with DNA to deplete surface oils if it is a concern.

Roughing up the surface and wiping with DNA are both counterproductive.

I think, Barry, you should add a reason why.

I have a friend who builds A LOT with coco. His advice to me when I first started usig his wood was to forget titebond and use Elmers Carpenters glue.
That was many builds ago and I habe never had a failure of any kind.

I've built several guitars with Coco back and sides, and/or fretboards and bridges. I've used LMI glue and regular Titebond with success and no known failures. I glue fretboards with epoxy regardless of species.

I've heard the "to rough or not to rough" arguments for decades. In my personal experience, if the joint is well fit and everything else is right, it doesn't matter. When I was a student at Galloup, we were taught to scuff Ebony bridges prior to gluing and I think Bryan Galloup knows what he is talking about. These days I don't scuff because I don't think it is necessary, but I've glued plenty of scuffed bridges that stuck tight.

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It will probably be alright.

I don't want to answer for Barry, but to me, roughing up a joint is essentially introducing sawdust into the joint, and this will weaken the glue line the same as leaving dust in a well mated joint will.

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

Gorilla white PU glue. Just finished gluing another 4 piece coco back. I have some leftover scraps for binding so thanks for the tips above .I have some elmers yellow.Was planning to use fish glue

I was just curious about the "counterproductive" part. When I think of roughing up, I mean 80-100 grit paper.

Roughing up will basically reduce the surface area of the glue joint.

Mike, I asked about this a while back as well- specifically wiping with DNA before gluing. A couple members said that it would just draw more oil to the surface once it was glued and weaken the joint.

I haven't had any issues gluing coco at all so far and I've just been scraping and using Titebond II or West Systems Epoxy.

A smooth, planed surface maximizes the strength of the glue joint unless you are using epoxy.

I have build 3 guitars with cocobolo back and side sets. I have had no problems with LMI instrument glue or titebond 2. I did have problems gluing cocobolo bindings to a cocobolo fretboard. I used thin CA. I had them clamped for long enough for them to cure, 30 minutes or so. The bindings came right off. I cleaned the fret board and the bindings up and reglued with LMI instrument glue with no issues.

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http://www.Harvestmoonguitars.com

Two people have mentioned using Titebond 2. Is that just with cocobolo or in general? I haven't heard of anyone else using Titebond II for guitars.

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Pat

“Roughing up will basically reduce the surface area of the glue joint.”
Huh? Roughing up is essentially adding peaks and valleys. IIRC the shortest distance between two points is a straight line.

https://www.popularwoodworking.com/tech ... h-or-rough

I stand corrected.

Huh? Your logic escapes me.

Well this link will explain the logic if you read it through. I’m not advocating using less than a smooth surface which is what I always do. Merely pointing out that roughing a surface increases the gluing area but does not necessarily increase bonding strength.
Respectfully submitted.
Tom

I don't see a link.

Roughing up the wood will increase the surface area of one of the pieces of wood, but that is not what I am talking about. The important factor is how much of one side makes close contact with the other side. To do this you need both sides as smooth as possible. Placing one mountain range upside down, and on top of another mountain range will only give you contact at a few points. Not good.

The link I think he is talking about is in my post above.