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What method do you use for making double sides and what are the pros/cons?
I am thinking of trying them in a form with a vacuum bag but would like to hear about various methods first before committing to that.

Thanks

I use John Bogdanovich's method. Burton does something similar

Thin the sides to about .065 and then use two thin softer woods (I use Alaskan yellow cedar). Pre-bend the side, place in the mold and then just glue and clamp closed with a caul.

The sides are light but very stiff.
Steve

Steve, do you mean there are two extra veneers glued on to your "proper" sides?

Looking for more perspectives yet, and can anyone speak to the method I mentioned? Does a vacuum bag apply sufficient clamping force?

Have you looked at Burton's Documented Build in the fixture & tutorial section?

He epoxies then together in an external form with a bunch of clamps.

Kevin Looker

_________________
I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

Edward,

I have not tried the vacuum approach. I imagine it would work fine. You may have to make an inside caul or a solid internal form but then again maybe not. If you do try it I would be interested in how it worked for you. I feel like I have seen people who do do it that way and I wish I could remember who and point you in their direction but for the life of me I cannot remember.

I haven't had any problems with the "lots of clamps" approach but it is a bit of a pain getting them all on and power squeezed. If the bag worked well it would be easier.

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Burton
http://www.legeytinstruments.com
Brookline, MA.

I made all my moulds so that I can bolt each half side by side and have a outside form for gluing double sides. For ebonies and rosewoods I thin each slice to .040" and don't even bother bending them. For soft woods (like POC on the pics) I pre-bend the thicker sides. The glue is Weldwood Plastic Resin Glue.

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

Laurent,
Have you had any bleed through with Weldwood on porous woods like Mahogany? I had some problems with that using Smith's All Wood Epoxy.
Thanks
Terry

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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 seem to add the link, something about an invalid mht, but
Do a search in the OLF, for "ernie" dated April 12 2011.
this is a recent discussion, including what I do.
Mike McNerney

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Mike McNerney

No bleeding through with Weldwood, Terry.

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

Thanks a Million Laurent

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

You're welcome Terry. Two things with Weldwood: one should wear a dust mask when mixing the powder with water, there is formaldehyde in it if I recall. Once in paste form I would think it's perfectly OK. The other is that it needs to be under clamps for 14 hours, and it takes another couple of days to fully harden. Then the laminations ring like a gong, and the glue is glass hard.

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

Got it. I've got plenty to do in the shop so I'll probably just leave the side clamped up in the form for several days.

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

Ureaformaldehyde glues like Weldwood plastic resin glue are nice because they have a long pot life but you can also expedite the curing by adding heat.

The cured resin also sands away very cleanly.

Kevin Looker

_________________
I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

I'm using laminated sides and thought I had a picture of the setup I used, but I could'nt find it. My laminator looks like the ones used for heat bending sides, but instead of 2 sides with spacers between them, mine is made of several layers of mdf. I have a mdf die that presses the laminations together at the waste, with a .020 thick piece of stainless steel between the laminations and the die. I've got all thread attached to the ends of the stainless band, which gets anchored to the bottom of the mold and tightened to compress the laminations. I used to use Weldwood for laminating but found a better product, Unibond 800. It comes as a liquid to which you add their powdered hardener and the hardener comes in different colors to match various woods. The best thing about it is a blocking agent that you can add to it to minimize bleed through on open grain woods. It isn't cheap and has a shelf life, but I won't use anything else now. Mike