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Looks good eh
?? Am a fan of double sides , like the the extra rigidity when assembling the instrument. I/ve used white glue, titebond 1 and epoxy, and UF glue to make double sides. Only downside to using UF , is cure time. In van it would take much longer in the cool weather , than here in OK. we have long hot summers.

That just might be my favorite of all of your guitars I've seen!!! Well done.

I also laminated my first set of sides this year. I had the same problems you mentioned. After a lot of thought, I think if I do another I will make a form with the outer one about 3/4" clear of the inner. Then I'll put the wood in with TB between the layers, fold a bicycle tube in half and place it between the wood and the outer form. Then pump up the tube, or tubes if needed, to apply even pressure on the laminate.

Just an idea, but it might work.

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Joe Beaver
Maker of Sawdust

I've been using UltraCat adhesive from Veneer Supplies (veneersupplies.com) for constructing laminated sides. It's a one-component, water-activated system that sets fairly quickly yet leaves time for a slow worker like myself to get things aligned in the press. When set, the adhesive is very hard; you could cut yourself with the residue in the mixing dish. The resultant sides are flat and actually do have a tap tone!

I have a question for those who laminate sides. This really goes back to Ed's original post in this thread, and reminds me of something I thought when I first read the Bogdanovich book on guitar making. Keep in mind I have never laminated sides, but I am tempted to try.

When constructing a laminating form, I see some folks making an outside form (like a body mold, only taller) and an inside form. Both seem to be of very rigid, unyielding construction. But I speculate that having one or the other be a bit flexible along the length of the mold, but still rigid across the width of the mold, would work better. If we were laminating straight material, then matching rigid forms would make sense. But because the material is expected to conform to a curve that eventually makes two 90 degree turns (one at each end), there is not a good way to clamp a rigid form to a rigid form and get a good fit everywhere along the curve. To be more specific, you can get a good fit by clamping at the waist area, but how do you then get a good fit up near both blocks if both forms are unyielding? If you could make the outside form unyielding, but make the inside form thin enough to flex a bit along its length, but still stay rigid across the width, then you could clamp all along the side's outline and get a good fit. But this could all be wrong. Can the expert laminators give some guidance on this notion?

This is exactly why I prefer vacuum. I use a solid bending form, so it's as easy as sliding it into my vacuum bag with a layer of breather mesh. I have seen people with segmented clamping cauls, but I like the even, easy pressure from vacuum. I'll be making a rim set in the next month or so once we get settled into our new house. I'll make a tutorial to demo my process. It really is pretty easy.

The vacuum approach sounds interesting; I look forward to your tutorial, James. I've taken the approach of using a rigid inside form and a slightly flexible outside form. The working faces of both forms are covered with thin, resilient carpet non-slip (a bit like non-slip shelf liner) and then clamped extensively. I make my sides with 6" wide veneer strips and, after they've set, cut them to shape with the band saw. That exposes edges that are hidden when the sides are clamped and I've not found any voids. The gap-filling characteristic of UltraCat (or any epoxy) is, doubtless, helpful in preventing voids.

Most folks I’ve seen use a hard outer with malleable inner, and I think I’ll modify my approach as well. I was in a hurry so I did it the long hard way...

I tried both outside and inside clamping molds and wound up preferring the inside which can also serve as a bending form. I found it easier to position the clamps.

You can make close fitting cauls with Durham’s Rock Hard water putty. With a flat piece of wood you can make a dam around the edges with tape, fill it with the putty and press against the mold which has been covered with clear packing tape. Once dry and trimmed up I cover it with 1/8” gasket cork to self level small irregularities. You can also rough shape the curve on the spindle sander and use the rock hard to fine tune the final contour.
I have had good luck with this clamping system on many guitars but vacuum looks ideal. I am just not set up for it yet.

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

Do you put the whole form into a bag, or add the sides to a narrow bag and place that over a form? If the former, what material is your bag made of and what size bag do you use? Oh, and do you do a cutaway?

I tried putting the whole form in a 24" x 48" bag made of vinyl:

https://www.veneersupplies.com/products ... 2-x-4.html

And could pull a vacuum in the 22-24 in/Hg range. Did not get great adhesion, especially in the cutaway. Using epoxy. I have few problems with adhesion putting the sides into a 6" x 36" bag and placing that into an inside/outside form. But it's fiddley. If I could put just the male form in a bag it would speed the process up quite a bit.

I actually think we have the same bag. Mine is also a 24x48 from Veneer Suppliers, but I can’t remember which. They had three at the time; I ordered the mid-range bag. There was a slight leak where the hose went into the bag on my last set and I only pulled 17 Hg, but I still got great adhesion without gaps using .06” laminates and Unibond.

I use a solid mold for sides and cutaway. They double as both my bending and laminating forms. I put a layer of wax paper or parchment paper down to protect them from the Unibond; spread the Unibond with a foam brush; set the two layers down on the mold; tape them in few places to keep them from shifting before the pressure’s applied; (ideally) lay the breather mesh on top; and slide it into the bag.

I’m attaching a few pics to help illustrate this. Crossing my fingers that they’re high enough quality after compression!










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One question Jim, With my cauls and a little residual spring back in the wood it usually takes pretty firm pressure to get the waist snug against the form and the same with a tight cutaway as with an archtop. Is vacuum strong enough to get a tighter waist or cutaway down snugly?

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

I can't speak for Jim, but my experience with vacuum bags yielded insufficient vacuum in the deep recesses of waists and cutaways.

I took my better shots with my DSLR, but those are on my external drive at home. I’m attaching what I have on my cell phone. I had to really zoom in to get this crop. Unfortunately it’s the best I can do for now. Pixelated as it may be.

Long story short, I haven’t had any problems with a waist or cutaway with vacuum. You can see the waist in the shot above, and this is the cutaway from the same guitar.

I decided to use vacuum because I saw Ray Kraut doing it when I was tooling up for double-sides, and I liked the idea of being able to use vacuum for bridge clamping and work holding, too. I had to either buy a pump or a bunch of new clamps. I went with the pump. I see on Instagram that Stephen Strahm and Tom Sands using it for laminating now as well.

My experience has been that vacuum pulls those laminations down flat against the form. The breather mesh may help, since it keeps the bag from binding down against whatever you’re clamping.

The bag material matters too. Vinyl is not as flexible as polyurethane. The PU stretches into deep recesses better. But even so, I had better results by using a caul in a sharp waist bend.

I’m going to give the vacuum a go. I’m assuming I can make a cork lined caul top and bottom and clamp outside the bag after the air is out?


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I put the caul inside the bag and let the vacuum clamp it down. I think of it as being there to fill up the space in the deep valley so the bag doesn’t have to stretch as far.

But take my words with a hefty grain of salt. I’ve done exactly 1 (one) guitar with laminated sides.

Oh - I should also say that I used an inside form and the whole setup was inside the bag. Inside mold, wax paper, wood layers with glue, wax paper, outside caul in the waist. All of that inside the bag.

One of the beautiful things about luthiery is that we all do things differently and constantly learn from watching each other. If I were to use a caul, I would personally just prefer using clamps. Simon Fay has a wonderfully thought out system with a cork-lined caul in his shop images: http://www.fayguitars.com/Guitars/Gallery/shop.html

Thankfully I've had good results so far (as you can see in the pics). The more I've thought about it throughout the day, the more credit I give to the breather mesh. It prevents the bag from binding and allows it to slide along the work piece as it conforms to the shape so it doesn't have to stretch.

Whatever approach you choose, I'm certainly interested in hearing about your experience.

I ordered the bag, valve and mesh. I will post some results. I’ve used several different approaches for laminating the pieces I use for solid lining. They work ok but are very fiddly.


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Are you guys and gals pre-bending the sides before laminating them together?

Thanks, M

I do it just as Simon Fay shows, vacuum bag for the lamination and a sandwich of cauls for the shape. But I will try putting the whole enchilada in the bag again. I feel that if I can get that to work it will be more consistent and quicker.


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Ps: what veneers do you use? Do you thin stock on a wide belt sander to your own specs, or are you buying pre made veneer? Do you use standard 1:40” veneers or is there a source for 1/20” or 1/16” veneers of high value wood?


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Yes. I bend the two lams together in the bender at the same time. They are already profiled off a template so they are exactly the same shape and length. If you do that they fit together perfectly.

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

Morning, guys!


Definitely pre-bending!


I like to use .06" laminates, so my rim's right around .125" when it's all said and done. I'll run my show side through the sander to get there, but I really like using LMI's sides for laminating for the inner layer. They're inexpensive and ready to go. The rosewood also makes for a stiff layer if you're using a medium density outer layer like a walnut, koa, mahogany, etc. The .06" layers are also extremely pliable, which may also contribute to not running into the issues with vacuum others are mentioning.