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I am just starting only on my second build so still don't know my arse from my elbow, but most of the builds I looked at before having a go myself start assembling the top and back to the sides by gluing the top on first. It struck me as odd when I then glued the back on and wanted to clean the squeeze out that it would have been easier the other way as the back is visible from the sound hole, whereas any mess fron squeeze out on the front is not visible once the box is complete.
Is there a reason that I am missing why most builds do the top first?

Many thanks

Lee

I do veneered sides first to end blocks create back dome on sides glueback, then flat top.Others do it the opposite way??

I glue the back on first for easy glue cleanup...

I too wouldn't mind a run-through on this topic!

My first two have been sides to top, then back. On #3, I'm planning to do as Ernie outlined, but I haven't yet found suitable reading material to prepare me.

It's still visible to anyone with a mirror

I assemble top first because I complete my neck set without the back glued on. Then glue on back and simply don't worry about squeeze out.

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Thank You and Best To All

Classical or Steel String?
Classical guitar (in particular Spanish style) tends to be top first (top facing down onto the solera), sides onto top and back after that.
I haven't build any SS but I guess back 1st is more common it seems.

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

There are a number of popular build methods. To mention just two:

1) The traditional face down, free assembly, solera style, Spanish heel method, which usually has the neck as an integral part of the assembly, with the sides glued to the face down top then the back goes on. It's a method more commonly used for classical guitars

2) The spherically dished work board, go-bars and outside mould method, usually with the neck as a separate part, assembled after finishing. The sides are held in a mould to keep everything in register and whilst the top can go on before or after the back, it makes most sense to put the back on first. One reason for this is that it makes glue clean-up easier, but the main reason is that with the sides and back in the mould and the top dry assembled (not glued) it is possible to make sure that the curvature of the upper bout is absolutely correct to give the right neck angle to deliver the right string height at the saddle and the right action with the neck coplanar to the upper bout. This method works fine for both classical and steel string guitars with separate necks, but is probably more popular in the SS community.

Each of the methods has its benefits and advocates, but for mine, I want repeatable precision and a separate neck, so the second method has it over the first. Others will, of course, differ!

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Hi Trevor,
Is it possible to build "freeform" using method 2? I mean, does one have to use the outside mould to glue with a gobar deck on radius dishes?

I'm probably the odd man out I'm sure, but I switched from back first to top first a couple of years ago. I like the ability to refine the braces after the top is glued to the rims, putting the top on first makes this much easier.

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Jim Watts
http://jameswattsguitars.com

I've only made 2, so not really qualified to comment, but I do the same. I thought I had gone light enough on the braces before gluing the tops on, but when I did, it sounded dead, so I carved some more. Obviously if I had more experience, that probably wouldn't be an issue.

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"I am always doing that which I cannot do, in order that I may learn how to do it."
Pablo Picasso

https://www.facebook.com/FenskeGuitars

I've switched to putting my backs on first. Primarily for glue cleanup but in doing so, I came across another benefit. Now when I glue the inside strip on the back of the guitar, I only glue in the section that goes between the back braces. I glue the strip in and then install the back braces as per usual. So with the back installed, it looks like this:



Then I can custom fit the two pieces that go between the braces and the head/tail pieces. Voila - nice and tight!



I should preface all of this by saying I'm still a complete noob at this. I'm sure the pros can glue in, install and cut the back strip to length and make it perfect right out of the gate, but for me, I like extra level of security knowing I don't have to cut it perfectly.

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Rob Flindall
Flindall Guitars
http://www.flindallguitars.com
https://www.facebook.com/FlindallGuitars

I have never built a guitar before, in fact, I have never held one in my hands. But I would glue the back on first to cleanup the glue squeeze out because we all know that that makes for best tone.

Thanks Rob. That is something I've always struggled with. Can't wait to try it!

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Pat

The way I do it is:
1. Put the sides in the mold with the top of the sides flush to the mold. (I put 1" blocks around the top of the mold and flush to that). I leave it in the mold until both plates are glued in.
2. Notch in the back braces
3. Notch in the top braces
4. Glue the back in place
5. Put the top in place and clamp down. Then I check the relief at the bridge area with a straight edge held against the fingerboard extension area. If that is right I glue the top down.

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Joe Beaver
Maker of Sawdust

I'm not Trevor, but sure it is! However, as he said, each has it's pros and cons. You just need a way to stabilize the neck angle for that particular build style. Hence the outside mold.

I build steel strings on a workboard, so I glue the sides to the top whilst it is facedown. I use a shoe to hold the neck at the correct angle when the back is glued on. consistency and repeatability is not an issue with this method, but my top geometry is not strictly speaking an even dome.

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Old growth, shmold growth!

This is my process lately.

Brace top, carve close to final while I can feel the flexibility.
Glue end blocks to top (including the neck if integral)
Glue sides to end blocks.
Glue dentellones.
Taper the sides.
Glue side braces.
Glue back linings.
Glue bridge.
Spool clamp the back on dry, tap all over. Shave top and back braces until it sounds good.
Glue back.

I like being able to hear the tap tone with the top perimeter constrained, so I can finetune the braces at the perimeter. And doing top first allows gluing the bridge, which gives me the closest impression I can get of the closed box tap. Plus you can even put a couple strings on it

Filippo, I measures the deflection of the top once it's glued to the rim and can adjust it if it's different than what I'm shooting for. I'll also tap it and get a frequency response to get an idea of where I'm at. You're right it'll change as you continue on but not a huge amount, it's not like tapping a free plate, it gives you a clue as to where you at. It's also easier to here just the top as it's not overwhelmed by the air resonance of the box. My experience is that I'll be slightly higher in frequency at this point than what the guitar will finish out at.

I think Dennis's comment on the perimeter and finger braces is spot on BTW. If my local deflection looks good at the bridge but my frequency response is high I'll work on the perimeter some.

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Jim Watts
http://jameswattsguitars.com

Thanks theguitarwhisperer,

I'll have to think about it. Maybe I should just use a form after all... I didn't like the idea of making a new form for every guitar I build (I certainly don't plan to build two the same for some time yet) but maybe I'm just being lazy.

I built my first two the way you outlined, and everything went well enough, I just didn't like clamping down on the cork shim around the perimeter of the workboard so the radius dish really appeals to me.

I also like the idea of using the radius dish to prepare the sides for the back but once again, I need to find some reading material or advice about that. I imagine most would recommend having an outside form for that, too. Guess I'll probably have to make one. Wish I had power tools sometimes!

Thanks again!

It's possible to mix and match all sorts of building methods, but the downside is that you tend to loose the benefits of having an integrated assembly system. For my method 2 for example, you get the benefit of being able to sand the rims with a radius dish to get a perfect fit. Of course, there are other ways of doing this, but it sure is handy. If you want to glue a back on, you can put the back in its dish, put glue on the back linings and drop the sides in their mould onto the back. Sometimes just the weight of the mould will close the joint perfectly, but a couple of clamps or a few weights can be added, or stick it on the go-bar deck. Heaps faster than messing with 50 or so clamps around the guitar, then trying to lift that lot off the bench so you can do other stuff. Likewise, you can clamp the whole of the lower bout of the top by inverting a dish over it and adding weights or go-bars. If you're into hide glue, there's no faster way of closing the joint. So there's all sorts of knock-on benefits of using a well integrated system. The extra space and cost involved in body moulds is balanced by the the savings in buying clamps and storing them.

Have a look around my website (see below).

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

If you use the gum method of attaching the Back you will get very little glue squeeze out, which is why I can glue the Top on first.

Hello Michael, can you elaborate on "the gum method"?

Thanks!

Rob

You create a Gum, as in Gummed envelopes. Doubt it will work with Titebond but it works with Hide Glue. You just coat the rims with Glue, allowing it to dry. You might need two or three applications. Moisten it, put your Back on and heat through with a clothes iron or you can feed very dilute glue in with a palette knife.

for me it's top first, brace refinement, then back. the top is bound btw because it does make a difference. i've noticed that that cutting the binding channel drops the top pitch a lot. adding the binding brings it back up to just slightly higher then where you started. i can also check neck alignment, hardware fit up, bridge pin placement etc... imo there's just so much more control in doing the top first. my current problem is that i'm doing small guitars and my hands don't fit through the soundhole!

I also haven't built any guitar nor have I held one in my hands, but what you said is obviously the truth, specially for people playing while looking at a mirror inside their guitar (as JF wisely pointed out).

More seriously, I don't give much consideration to glue squeeze-out, as I put just enough glue not to have glue drooling on the sides. Thus I glue both top and back at the same time. That said, I wouldn't advise beginners to do it this way. You sort of have to know what you are doing before you go this route.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)