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A question for traditional classical builders. When you glue the back on with the guitar face down in the solera, how do you deal with squeeze out inside the guitar?

You don't. Just use the right amount of glue.

You assemble it with top and back, but only glue the back first. When the gobars come off, take off the top, and clean out the squeeze out. Then glue the top. The top is face down of course and any squeeze out will stay there, and not be visible when you look in the sound hole.

This works great; I learned it from Robbie Obrien,
Mike

Mike, in traditional classical guitar building on a solera, the top is assembled to the neck before the sides are even added. Then the assembly is placed face down in the solera, the sides are added first, and then the back. I'm not sure we are talking about the same thing here.

Think for Mike's method, the top and back and side/neck are 3 separate parts during assembly.
Instead of gluing the neck to the top first, the sides are glued to the neck forming a rim.
During assembly, the back is glued on to the neck/sides rim
Glue squeezed out are cleaned.
After that the neck/sides and back are then glued on to the top.
One potential error is that the neck centre line is not aligned to the top's so some sort of aligning pin might be good.

For traditional method, the assembly sequence is different.
The neck is glued on to the top, ensuring that the centre line of the neck is aligned with the top.
The sides are then glued on to the neck and top.
Finally the back is glued on to the neck / sides / top, fixing the neck angle.
It will be almost impossible to clean the squeeze out so like what John suggested, you applied just enough glue to avoid the squeeze out.

For me I think it's better to apply more glue then less.

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Sen CL Goh
http://senguitar.blogspot.com

I'm with the right amount of glue. One trick is to generously apply the glue, then sort of go around the inside edge of the linings with your finger and sort of pull the glue back from the edge slightly. There is still glue there, but just a film. This forces he squeeze out to the outside of the guitar where you will clean it up as you trim the back overhang to the sides.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Not much wrong with a little glue squeeze out. It was good for Torres. Just do what Waddy wrote and you will be fine.

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Ken

OK, thanks everyone. I guess trying to use the just right amount of glue and wiping back a bit like Waddy said is the way to go.

Same as Waddy, and I just thought I'd mention that I find I get less squeeze out using reversed kerf linings (titebond in my case)
I think some of any excess glue goes into the kerfs and so is invisible.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I'd agree with that. I happen to use the A-4 Linings that Kevin Ryan sells, but it has similar properties to reverse kerfed linings in that it soaks up a lot of squeeze-out.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Wendy, I think Sen described the sequence I was suggesting in his post.

I build on a solera using my sequence, but but I do use a mold first so when I get to the solera, I have rims/neck/linings and tail block already glued. Sounds like you are building sans mold, and the "use the right amount of glue" technique is probably best for that,

Personally, I always worry that I might have a starved joint if I don't see some squeeze out, but plenty of people are very successful using just the right amount. To be honest, I probably overthink/worry about a lot of the process!
Mike

I'm a little late to respond on this one, but all I've built so far are classicals after Cumpiano and Natelson (I am looking forward with some trepidation to a bolt neck on one of my next builds). I am careful in the amount of glue supplied and as a couple of builders have said, I switched fairly early to reverse kerfing; l like the look and much of the squeeze out gets captured in the kerfs where you can't see it.

Thanks for explaining Mike. Have you got any pictures of your early process when it is in the mold. Would love to see it. Wendy

I have most pictures of the process, but I -think- these will show what I meant. If not, just ask!
Mike

Very interesting, thanks Mike! It all makes sense to me except I am having trouble visualizing the process of leveling the top kerfing. I'm used to using tentallones on the top. So you glue the top kerfing, and then sand it level it to the sides which are already level with the shelf on the heel block, or do you just carefully install it to be level to begin with?

Also, what do you think is the advantage of this process as opposed to assembling the top to the neck first and then building face down?

Glad that helped Wendy,
Yes, you are right on the top kerfing. I just start with perfectly straight sides on the top side, and glue the kerfing level or slightly above level. Then a few minutes with a block plane or sandpaper board and when you see you are touching the sides all the way around you know you are flat.
I think there are advantages to every method, or they wouldn't continue to exist, but the advantages I see to this method are:
1) The mold aids in symmetrical sides and keeps them perpendicular.
2) It allows you to use reversed kerfing top and bottom which I believe stiffens the guitar and helps isolate vibration to the top.
3) It's really easy to sand the radius in for the back when the assembly is in the mold.
4) You can make sure your neck is pointed to the c/l of the endblock before gluing, and tweak as necessary if it doesn't. I still check neck orientation during final glue up on the solera and clamp it on centerline, but it is nice to be correct or close when you start.

And....you can glue the back on first and clean out the squeeze out before gluing the top on! j/k.

I've found most people instinctively gravitate towards the processes that make sense to them and compliment their skill set. I know I do. And I'm not a purist, I steal from various styles of building that make sense to me, where someone with different skills or tools might well go a different way.
Mike