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There's been a recent thread about this http://luthiersforum.com/forum/viewtopic.php?f=10101&t=49881&start=25 and I have a question. Has anyone used their bending machine (I use mine with a blanket to bend the sides) to stick the two layers together with epoxy? I've sanded Black Walnut (whoops got them a little thin) and Mahog 2nds to .05", will bend them together and later glue them with West Systems. Just trying to keep from building another jig....Thanks,

Carl

I think many of us who use a block form for bending with a blanket also use it for laminating sides.

My laminating form doubles as an outside mold. Opposite side of the same coin.


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So long as your using an solid form for bending it'll be fine. The bending forms I use would not work. The forms some folks use would.

You'll still need to make a clamping caul to ensure you're applying sufficient/even pressure.

I agree. Even with a solid bending form the slats of the bender will be inadequate for even distribution of clamping pressure. You need a good caul system to use with the solid form. Plenty of threads on this with the search function.

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My form is made out of MDF and is solid, no slats. I was thinking of drillings a series of holes in the sides of the form to allow me to use that as the form for joining the laminations. Or as rlrhett suggested, i may use the outside mold. notg sure which will be easier or work better yet.

Any suggestions on the type of epoxy to use, or is one the same as another?

I personally like using Unibond (urea formaldehyde resin) a little better than epoxy.

I have an older alum overholtzer bending jig, I like uf glue, but I laminate the veneers .022 to the main hdwd e.g EIR before bending FLAT. I used a 3/4in mdf flat caul. Then I bend on the bending jig vy slowly There is also a simple laminating caul jig in the bogdanovich book I made one , but it requires a lot of clamps and clamping .I ran out of time ,doing it that way and had gaps in warm weather when using titebond

Thanks for all the input. My basic intent was not to build another jig (and since I have been building several different shapes, not to clutter up the shop with several) and to use what I already have. So, based on rlrhett's suggestion, I'm stacking the outside mold halves to get the depth of the sides, making inside cauls with Bondo or Durhams for the shapes, Formica or thinned masonite for even support and HF $2.99 F clamps to squeeze'um. Registering on the outside mold should make the sides fit best.

Thanks again ..

Carl

Carl FYI I have about 35 of those HF clamps IMHO they don/t exert enough pressure for laminating a 2 or 3 part sides. I/d use a better quailty clamp that can exert more pressure (bessey).. Test your HF clamps on scrap first .If their like mine , we only use them for minimal pressure and a very close fit !!!. My favorites for good laminating pressure are HD metal F clamps with rubber handles from hartville tool in OHIO . IMHO they are an exc buy and exert moer pressure than the bessey and made in china, Less $$$

I should point out that I vacuum bag the sides for two hours first before putting in the form to assure good lamination.

Using West 105/206 Epoxy.


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I've had good luck with the harbor freight F body clamps, but I do set them as close as I can. HF clamps have improved over the years and are much better than they used to be.

Tnx clay my HF/s are like 8-10 yrs old . I/ll check the new ones

Well, here's what I came up with, outside mold with a spacer and extension to go in the vise. Inside mold waist and lower bout forms with additions and other scraps to make the cauls and 25 HF clamps. I used some Smiths All Wood Epoxy and we'll see tomorrow how it all worked out......

Carl

Nice looking rig, Carl!

Alex

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Here is a picture of mine. Very similar to others:




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