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My supplier provided me with three veneers for sides each about .020". Once glued up I expect it will be around .090". Is this too thin? Also, it would appear that using a vacuum bag setup would be the best way to glue the sides up, but I don't want the expense of the setup. Anybody use some other type of jig to glue up veneers. I'm interested in your experience. Thanks

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A higher purpose for wood.
Rich Smith
Issaquah, WA

You're going to struggle with them being this thin. Sanding through a layer will be VERY easy. I use .04" pieces (2 of them) and it is touchy sometimes with that thickness.

I use a full width inside form cut to .10" smaller than the actual side then layer up on top of that. I prebend the sides in the bender then use West Systems epoxy 105/205 to laminate them. I started by clamping them, but that was slow, the pieces slipped during clamping and was overall problemmatic. So now I use a vacuum bag (put the form and the sides in the bag), and that works really well.

One thing you are going to want to do is seal the pores in the wood before you put it in a vacuum bag. Before I laminate, I coat the very most inside and outside surface with 7 light coats of shellac (not the part glue will be on, just the outsides). Otherwise Epoxy will leach right through the sides and you won't be able to sand it off. Clean up is much easier when you lay down the shellac first.

The only other advice is to remember to coat your forms with wax paper.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Rich-
Excellent advice from Brock, so I don't have much to add. I use vacuum to laminate sides as well.
I'd definitely make the outside layer thicker as Brock recommended- I use about .060-.070" outer layer with a bit thinner inner. Using thin veneers for the outer layers is quite risky - any bubble or curl will mean a sand-through. With an excellent (smooth) form and good vacuum, I'm sure it could be done, though.

Bogdanovich has instructions for laminating sides without vacuum in his classical guitar-building book. That, and the wheat purfling instructions make the book a good resource even if you never build a classical, IMO.
I did one set of laminated sides with the clamping method and it does work, though you need to make some extra cauls.

If I thought that the acoustic properties of the sides were very important, I wouldn't laminate them. Once I decided to laminate sides, making them a bit thicker didn't seem to me to be a problem.

Cheers
John

PS: You could contact Jeremy Clark for some ideas:

Brock is right. With thin laminations like this you'll need a lot of luck not to sand through. I also use 2 x .040" layers. I set up my molds so each half can be assembled side-by-side and serve as an outer form for gluing laminated sides. 2" spring clamps and cauls and the glue is Weldwood plastic resin glue. It has a very long open time and dries glass hard. I use masking tape in 3 or 4 locations on the stack so that the laminations don't slide during glue up. Here's an old pic.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

I usually go with two .060" layers. But I have done an outer layer of .023" veneer and not sanded through . . . well, at least not where I couldn't add a "decorative" feature.

Epoxy creeps and adds damping. Probably not a big deal, but I use urea-formadehyde (weldwood plastic resin, but there are many others).

Vacuum can hardly generate the pressure needed for a tight lamination. I put as many clamps on it as I can, with fitted cauls.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Hey Howard... are you getting bleed through with that glue too? What is the dry time like?

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Bleed through depends on the wood, but it's never been much or a problem.

The glue has a long pot life--a few hours. But its open time after spreading on the wood is about 15 minutes, which is enough to clamp it with the 20 or so clamps I use.

Clamp time is very temperature dependent, and should be at 70º F. at least. At that temperature iirc it's about 12 hours; at 80º it goes down to about 8-9. Those times assume the joint is tight. Basically what this means is overnight will be fine. It dries very hard and creep free. It's easy to cut yourself on the edges of the squeeze out.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I use two layers .070 thick and glue them together with Titebond and clamped around a form.

These sides are very solid. After I've got linings, tail and neck blocks in I don't bother using the mold.

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Bob Connor
Geelong, Australia

Could anyone recommend an inexpensive source for 0.060" or thicker mahogany veneer, large enough for sides?

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David Malicky

You could try www.wood-veneers.com and www.certainlywood.com

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A higher purpose for wood.
Rich Smith
Issaquah, WA

David-
If you are looking for inner liner veneers and can thickness-sand, you could try contacting Allied for some 'orphan' or 'opportunity grade' mahogany sides and sand them down.
http://www.certainlywood.com has 1/16" mahogany veneer.
EDIT: Rich got the certainlywood.com typed in before me!

Cheers
John

Hi Ricardo,
In addition to the excellent comments above I would say that you could use the thin "standard" veneer. But I would make them 4 ply.

Thinner veneer will conform to a more radical bend as seen here. This is 4 plys of maple veneer with the show face of curly stock.

You can see my mold for laminating the sides. This only works with thin veneer. The trick is to put the veneers into the bag and put the bag around the form.

And the photo of that little log (38 inch diameter) is to prove I ain't no mamby pamby veneer guitarmaker.

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Ken

Ken, did you forget the link or pics? Thanks

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A higher purpose for wood.
Rich Smith
Issaquah, WA

Yes, Ricardo I edited them in while you were posting.

Consider bending your sides, it is a lot easier. You are making an archtop correct?

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Ken

Ken, I think you are right. I'll buy a set of sides and bend them rather than get all the gear to vacuum bend the veneer. Yes, those are radical curves. Do you mill your own wood? Thanks.

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A higher purpose for wood.
Rich Smith
Issaquah, WA

Not really, that is a huge white pine that I got from down the hill from here. It was standing dead for about a year and when the sawyer cut it down he left two 8 foot sections. I couldn't pass it up and called a friend with this loader thingy and he came an picked it up and took it to his place where we will cut double bass tops.

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Ken

Thanks, Rich and John, for the helpful links and suggestions.

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David Malicky