Binding problem - need some advice!

[brad barron]

Hey guys

I am finishing my second guitar build. This time it is the 000 kit from stewmac in rosewood.

Everything was going great. I started pumicing for the French polish and was on the home stretch. Then, the weather started to get a little dry and the problem hit.

It seems I did a poor job gluing the back braces. They are lifting off at the edges. The ends then are poking the binding and pushing it away from the guitar. I am guessing that part of the push is c'mon from differential shrink between braces and sides too.

When I routed the binding channel, the router trimmed off the braces. So - no room for movement. This is the same as my last build (mahogany 000 kit) and no issues there but who knows.

So....

1) in the future, do I need to trim the braces so there is a little clearance to the sides to allow for some movement?

2) for repairing the, I unfortunately think I need to strip off the binding, reglue and trim the braces, and rebind. What is the best way to get the binding off without damaging things? It is plastic binding applied with weld on cement.

3) if you have a miraculous technique I could try that allows me to keep the binding on, I'm all ears.

Tx guys.

[Mario Proulx]

Your guitar is suffering from severe lack of humidity right now. In other words, it is too DRY!! Get it some moisture, pronto, or the next question you will be asking is how to repair a top or back crack!

For the brace ends to have poked-out the binding, the back has had to have shrunk a serious amount. You either assembled the guitar when it was too wet, or it is too dry at this time. Either way, the only long-term solution is humidity.

[Michael Lewis]

I think the wood may not have been fully dried out, or it was dampened and swollen during gluing of the braces.

If the braces are coming off you might make sure you have the guitar stabilized in a good RH level before regluing them. Then deal with the binding and finish.

[brad barron]

well - the shop is 30% RH right now. A tad dry but not too bad. However, to be fair i don't pay as much attention to the RH on the high side. I did glue up the back this summer so it may have been moist.

Regardless - seems i need to reglue the braces and trim flush. Any thoughts on my original questions:

1) how should i remove the old binding - rout off or something else?
2) do i need to trim the braces a bit or can they butt up against the binding?

thx

brad

[Clay Schaeffer]

Routing off the binding would be the quickest way to go. If the back braces are "lifting off" at the ends you may want to remove the back . remove the braces, and reglue them (or make new braces if necessary) at the proper humidity levels.
I like to leave a slight gap between the binding and the brace ends. Braces don't shrink much in length, but the back will change in width. If the braces were not lifting off the back you might be able to just trim the ends a little bit and rebind.

[Doug Shaker]

Stewmac has some tools designed for gluing braces back down as a repair. If you search their site you may find the tools and videos on their use. You may not have to remove the back to fix it.

[Simon Magennis]

well - the shop is 30% RH right now. A tad dry but not too bad. However, to be fair i don't pay as much attention to the RH on the high side. I did glue up the back this summer so it may have been moist.

...

I have to admit not paying much attention to humidity at the beginning. However, the only really dangerous period here is winter when it gets really cold outside and the heated house can experience dramatically low humidity. I would imagine that Bejing has a way wider range than here. Having seen a top crack last winter after forgetting to check, I am getting almost paranoid about humidity. Naturally it wasn't one of my own - just the most expensive bought guitar I have in the house.

I would consider 30% pretty low and I would be also concerned about measuring it. Mario has a couple of threads here describing calibrating hygrometers. He is also in a climate where he experiences serious extremes. This is a must read: http://www.mimf.com/phpbb/viewtopic.php?f=12&t=1672

Old fashioned builders here in Germany in years gone by managed humidity fairly well but not in a "scientific" way. For example, they aimed to get all the bracing glued and the box close up in the same day. They would have been using hot glue so once everything was prepared, easily doable for a pro.
Here is an extract from the thread mentioned above:

I have perhaps $50 invested in all my hygrometers. I calibrate them often, and check them against one another daily. I have 3 in the shop, all placed together. As long as they're reading within 1% of each other, I can be pretty damned sure that everything is fine. When one of them begins to read different than the others, then it's time to check them, clean them, and recalibrate them. If you only have one, you have NO WAY of knowing, day to day, if it's reading correctly. I don't care if you paid $100,000 and it was personally blessed by the Pope, you have NO WAY of knowing that it is reading correctly.

p.s. I have only one -- but I promise I will get some more.