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I've just finished bending the maple sides on my latest archtop build and am not happy with the look. Physically the sides are fine but I want more flame. I am considering laminating the sides with some beautiful curly maple veneer I have on hand.

I've never tries laminating guitar sides before. What glue do you laminators use? Fish, titebond, contact cement, something else?

Epoxy.

Bob, I've had very good results with Unibond 800 mixed for quick set.

+1

Epoxy gives you plenty of time.
Also the veneer stays flat and nice, not always the case with some other glues.
I recommend West System and using gloves (nitril).

That said, I´ve only built two guitars so I´m by no means an expert..



Last build, Smoked eucalyptus.

+1 on Unibond

I've used epoxy and tb1 as well. They all worked but ever since using unibond for the first time it's my go-to for laminating sides.

I haven't done any laminated sides but if I was I would do it like this:

If you have a full depth side form, as Max shows, I would bond it with titebond.

For two reasons, I think titebond would be acoustically less intrusive than epoxy, and if you have any areas that didn't bond well, you can heat with a gun and use a veneer roller to remove the voids.

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Joe Beaver
Maker of Sawdust

Unibond 800 for me. It dries hard as glass.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Yep, Unibond is hard as they come and, IIR, unlike tb or the epoxies your likely to use, it is structural.

Tb1 is my least favored of the three. Not only is it the softest (...depending on the particular epoxy), but as it shrinks while drying/curing it causes an over-bend in the sides (nothing my solid linings couldn't cure but still...). Again, it'll work but my preference would be: Unibond, epoxy, then tb1, in that order.

I did a bunch of test sides using West Systems epoxy, Unibond, and Titebond. The epoxy and Unibond were quite similar. Both dry glassy hard; both bleed through the veneer some, and both are very strong. I finally decided to use epoxy mostly due to the fact that Unibond only has a shelf life of a year or less. Also, I do not like the formaldehyde off-gassing from Unibond.

Bleed thru...yikes!

Dark Unibond bleeding through light maple...not a pretty picture.

Any way to prevent that?

Yeah.... use ep*xy......

I have laminated Maple sides with Unibond with no bleed through. They do have a blocker available. Shelf life is an issue, refrigeration
can extend it quite a bit but I have had to throw some away that went too long.

I think Epoxy is fine too, I have used that as well (Smiths). I started with Tightbond and it was my least favorite.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

laminated sides...

I used to think that was some sort of heresy, then upon reflection decided it's a d*mned good idea

as far as construction, you've made life a tad easier in not having to use heat to bend the rims...as noted, if you're worried about bleed through use clear epoxy as Hesh suggests...if you're really worried then use epoxy to pore fill and any possible bleed through should be equalized out in the big picture.

as far as 'tone'...well, I came to the following thought process: there is a LOT of wacked out difficult math that needs be used when trying to define 'tone' in an acoustic instrument...a LOT of variables...by laminating the sides you have turned what used to be a variable into a constant...e.g. eliminated a variable and just made the math way easier...being very simplistic you've made the box into a 2 variable equation (top and back) as opposed to 3 variables...a win win scenario IMO

".by laminating the sides you have turned what used to be a variable into a constant...e.g. eliminated a variable and just made the math way easier...being very simplistic you've made the box into a 2 variable equation (top and back) as opposed to 3 variables...a win win scenario IMO"


How So?

I didn't have any bleed through with Unibond. My layers were each .06" thick, and the quick set mix was about the consistency of Tightbond. A decade ago I used it to veneer some offensively expensive Karelian Birch veneer to maple drum shells that was about .025" thick and didn't have issues the , either. However, if some people are having bleed through, I'm glad they spoke up.


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I, along with most who laminate their sides (I believe) still have to bend the sides. I'm typically using 2 laminates: the outer @1.25-1.5mm (depending on the mass of the material) and an inner lam of about 1-1.25mm. My sides end up 2.25-2.5mm thick.

As to the side variable in sound, I don't think the sides contribute much at all apart from a loss of energy standpoint. Having said that, when you make a guitar with thick laminated sides you loose less energy to the sides...trade-off being that you have a heavier guitar. The loudest guitars I've heard all have heavy laminated sides.

I personally don't care for particularly heavy guitars but like working with the nice, stiff sides and do think adding just a touch of mass there makes a noticeable difference in volume (I do try to find other places to drop mass to compensate and the overall weight of my guitars tend to be on the light-ish side).

I try to keep the mass of the sides on all of my instruments of the same size close to the same. I shoot for something similar to what you might end up with if using solid sides of a very dense wood like cocobolo-so on the slightly massive side but not overly so.

To keep things relatively constant I laminate denser sides like rosewoods, etc with softwoods inner lams like cypress, yellow cedar, or even sitka. For less dense woods like mahogany I'll use a hardwood inner lam.

@WilliamS - I use 3 layers of 0,6 ( one crossgrain like plywood) and don´t prebend anything. I Just press the flat veeners into the mould.
There is a bit of tension, but that´s good cause it acts as a bit of clamping help. I´m by no means saying this is in any way superior
to your method, but just for information. I believe most people building Selmerstyle guitars do the same.

When reffering to Titebond above, is it original Titebond or the Titebond made for veenering and pressing that we are talking about?

I had some bleedthrough on one build with epoxy, but it doesn´t show at all once finished, at least not to my untrained eye..

I know zero about laminating sides, but TB will be introducing moisture to very thin wood. I would guess that you would want to leave the sides in the forms for a good amount of time to make sure the moisture evaporates, or risk some deformation.

Alex

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Max, I was referring to TB1 (original).

I am aware that some guys are using commercially available veneers but it's been my impression-and I could very well be wrong here-that most guys are using somewhat thicker laminates that require bending, at the very least for the outer lam.

...bending lams that are thinner than solid sides is easier, though, and having the bend 100% perfect isn't an issue.

I'll also mention that I mostly try to keep up with what classical and flattop steel acoustic builders are doing. Using thinner veneers all around might be more common with arch top and selmer builders, idk.

I've considered doing a cross-grain middle lam, too (as many do), to make things split-proof and eliminate the need for cross-grain supports but I'm pretty satisfied with my process as is.

Uni-Bond comes in 3 colors. Light, med , and dark. Obviously use the light for maple. Bled through is not a problem, use Kraft paper or news board between your caul and veneer. Any bled through will be caught and absorbed by the paper keeping it from spreading. The paper/glue glob is easily sanded. You will never see it. Non-issue. Plus with maple I doubt you will have any bled through anyway.

L.

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Cut to size.....Beat to fit.....Paint to match.

When I laminate sides I laminate matched veneers in the same sequence they were cut. I use epoxy and pore fill with epoxy. Although there isn't much wood movement, you sometimes see face veneers checking on old plywood where plys are laid cross grain.

Clay, I would suggest that for a lay up where you don't see the edges (as with a guitar side) you flip (180°) your laminates. That way any weak spots, grain run-outs or anomalies are not lined up. Makes for a much stronger part. For a thicker parts where you can see all the edges as in furniture (chair back is a good example) where you don't want to see obvious laminations then sequential laminates are preferred.
If I were to pore fill with epoxy I would use epoxy to lay up my sandwich. Other wise Uni-bond.
If you are talking about plain plywood, with it's paper thin rotatory cut face veneers there is not really any comparison or conclusions to be drawn as compared to what we do. Any cracking or checking you see is a result of less than optimal construction and conditions you would hopefully never see in a guitar.
L.

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Cut to size.....Beat to fit.....Paint to match.