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I have started on my first two builds and I just glued up the back braces on #1 last night and I will do #2 tonight. Ok, I will admit, these are Appalachian dulcimers so I hope you all won't chastise me too much. My ultimate goal is to build guitars, but I thought dulcimers would be a good starting point. I have some questions about gluing up braces.

How much glue should I use? I am using original Titebond. The first brace I used about a one eight inch line, and then spread it out evenly all over the side of the brace to be glued. I got a fair amount of glue squeeze out so the next one I used less glue. It was enough to where it made a thin coating on the brace and I could see the glue soaking into the brace to which it made an even thinner coat after about 20-30 seconds. It did not have hardly any glue squeeze out.

How long should I leave the clamps on, under pressure? The Titebond bottle says to take the clamps off after 30 minutes. I left the clamps on all night, and took them off this morning. They all seem to be holding up well.

How much pressure should I use on the clamps? I would say the pressure I am using is just a bit more than squeezing your fingers and thumb together as hard as possible.

Any suggestions for keeping the braces from sliding while clamping? Cleaning up glue squeeze out?

Thanks for any advice you can give me!

I built an Appalachian dulcimer before my first acoustic too, good practice and they are cool instruments in their own right.

Glad to hear you're using Titebond Original. You want some amount of squeeze out so you can be sure you are getting good glue coverage but excess squeeze out doesn't gain you anything.

Titebond does not have to be clamped that long but I always leave mine overnight.

For braces I use a Go-Bar deck now but I would clamp them more than I can squeeze with my fingers but not enough to deform the wood. Don't know how to quantify that for you.

Things sliding around is a problem with lots of glues. Some parts can be pinned or temporary guide-blocks can be glued next to the part with CA to maintain position while gluing, neither of those is probably a good option for braces. Just have to bite the bullet and fuss with them until they are clamped right.

I use a damp rag around a sharp stick to clean squeeze out.

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Steve Smith
"Music is what feelings sound like"

Good info from Steve. As he said, TB doesn't need to be clamped that long, but a good deal of folks do clamp overnight. For things that are being glued without stress, like flat braces glued to a flat board, 30 mins clamp time works fine, but don't stress the joint for 24 hrs in any case. I allow more clamp time (a few more hours) if any stress is introduced to joint, like if the braces are arched and being glued to a flat top to form a dome. I don't know if this is necessary. I've never felt the need to find out and don't want to risk having the joint creep. Maybe someone else can educate us both here.

As far as pressure, it doesn't, or shouldn't, take very much to glue braces. I don't know how hard you can clamp your thumb and index finger together, but I would guess if that same amount of pressure is applied over the length of the brace being glued, you're fine. Go-bars, individually, don't apply a great deal of clamping pressure, but if you use enough of them, distributed evenly, they work great.

For cleanup of squeeze-out, another member suggested using the end of a plastic drinking straw. I have since tried it, and it seems to work great. Wait 10 minutes or so, use the plastic drinking straw end to scoop up most of the squeeze-out, and clean the remainder off with a damp rag.

Keeping braces from shifting is difficult sometimes, but if you hold them in position with your hands for a couple minutes the glue will start to tack a bit and clamping is easier. You might also lay a couple layer of painter's tape down on both sides of the braces to act as a dam to hold the brace in place while clamping. This also helps with cleanup. Remove the tape as soon as things are clamped in place for the best results.

Aaron

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Aaron Craig

these are all great ideas guys, thanks. i'll be down in the shop tonight and I will let you know how brace glue up on #2 goes. Im building two at once to get good experience by repetitiveness. I figure #1 is for learning/mistakes and hopefully #2 will be acceptable. So far they both have gone very well!

Your glue joint should be fit well "dry" . I use Tite Bond Original most of the time and some Hot Hide Glue . You should only use enough force to close the joint. There is no need to force a joint. A clamp should be tight enough to produce some squeeze out . This is a toughie as most beginners often use too much glue and that can be as bad as not enough.
Cover the joining surface with enough glue so you can see the glue and not so much that you can't see the wood . Place the wood together and tighten the clamp a bit more than finger tight but not so much that you are bearing down on it . Seldom will I clamp more than an hour but I have left things go overnight. If you clamped it properly this really won't matter all that much.
What I like to do with tite bond is after about 10-15 min the joint is tacked but the glue has not cured.. I release the clamps and clean out the squeeze out. The glue at this point has boogerized and usually comes of clean. That and a swipe with a warm wet paper towel or scrape with a razor blade to clean things up , then back on with the clamps for the rest of the hour.
I cannot stress the importance of a good fit . Forcing a fit is not a good thing as any joint that is forced is adding more stress than you should.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it