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I am curious what kind of set up people are using for laminated sides.
I have a 'outside mold' & I put the whole thing in a vacuum bag.
I saw a cello builders system, but I can't find the link anymore and would like to.
He had an outside mold (one piece at a time of the 3 for a cello) with some kind of seal around the perimeter & he puts the plastic on it & sucks there air out in a few seconds. With mine I am messing with the bag pushing it down in to the mold & it probably takes 5 mins.

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Mike McNerney

Look up Jim (James) Hamm.
Honestly though I think it's easier and more efficient without a vacuum set up.




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Ken

I'll second that, laminated sides is all I do. I use an outside mold, a 1/4" cawl on the inside and bunch of small bar clamps. Works great. Once I have the glue (epoxy) spread, I can clamp up a side in 5-10 minutes. Easy to keep things aligned and no worries about power outages or vacuum failures.

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Craig Bumgarner

Bumgarner Guitar Blog

I laminated my first set of sides last July using a 2x4' vacuum bag and Unibond 800 mixed for a quick set (directions are on the resin container). My mold was covered with wax paper and I usedbreather layer on top of the sides.

I pre-bent the sides, brushed on the Unibond with a foam brush, and used low-tack painter's tape to help keep the edges of the sides aligned to each other to minimize clean up later. Then I plopped them on a solid mold and slid the whole thing into the bag. Since I mixed the Unibond for a quick set, I had everything set out mise en place before starting so I could get it under vacuum within a few minutes of mixing the Unibond.

I took them out after an hour for a few reasons. One, I'd been monitoring the left-over epoxy*, and it was clearly set. Two, I was using a friend's vacuum in a 105°F shop. If everything had been mine and I could've gone inside to wait, I would've just let the vacuum run for another hour or two .

The fit to the the mold was incredible. If all you've done to this point are solid sides, prepare yourself for a moment of serious gratification. But just in case, I taped the sides to the mold to keep them tight overnight until the Unibond was fully cured and set an 18 lb. kettlebell down on the waist. The more professional amongst us might just use a bag of shot, sand, or some pie weights

Mixing the Unibond in a disposable plastic cup was what let me monitor the expoxy. When trying to pull the foam brush out reminded me of The Sword in the Stone, I felt OK taking the side out of vacuum.

If you're interested in seeing a quick video of the process, this is one I shared on Facebook.

Can someone advise me on which two-part products are epoxy, and which other two-part glues are not? I am extremely allergic to epoxy, and I do not want to accidentally use a product that has the same chemicals.

I've used fish glue for the one laminated project I did and it worked great. Plenty of time to get things clamped up and budge around to get it right. Have a look at Bogdanovich's website and he has some really nice videos on laminating sides.

I like epoxy because it does not hydrate the wood. When I first started, I used Titebond, then Weldwood plastic resin glue. Both are water base and led to considerable warping. Three months after finishing, I got shrinkage cracks in the finish. I'm convinced that any water based glue will do this. Epoxy is not water based. I thought it would be messy compared to water base glue, but on the contrary, it is easier to use. I use WEST epoxy, fast cure. I measure it out on a gram scale and am very careful about the mix. Use a disposable foam roller to apply. Wet both surfaces, roll out evenly, watch out for absorption, but don't put on any more than necessary to minimize weight gain and messy squeeze out. Always use disposable gloves and plastic sheet to protect work surface. Wax the molds.

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Craig Bumgarner

Bumgarner Guitar Blog

I started out with Bogdanovich's method and clamping form. I also wanted to get away from water based glues for the reasons mentioned and went from Tightbond Extend to Smith's All Wood epoxy and then to Unibond 800 which I like the best. I am in no hurry so I do a slow set mix.

I have gone through a bunch of clamping schemes. I currently am clamping to an inside form that also serves as a bending form and using bar clamps over kerfed plywood cauls with a fitted caul at the waist.

The Unibond takes a long time to get rock hard and brittle which is the endpoint I like so overnight clamping at a minimum for me. that kind of rules out vacuum.

Here is a form I just made for a 000 12

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

Uni bond is water-based.

You can speed up securing of these close to around a few minutes by using the heat blanket. Are use a silicone blanket. I can load the mold and pull them out completely dry in five minutes. Keep in mind that if you use the curve in there it's safer. Send veneer seems to crack
edit can't a guy just talking to his phone and get it right lol.

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Ken

That's interesting. I had no idea it was water based. It sure doesn't affect the wood and dries hard and brittle.

If you ever get a chance shoot us a picture of your setup with the heating blanket. I am intrigued!

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

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Ken

The jig should be designed so the gap is exactly he glueup plus three aluminum slats plus the silicon blanket. So the negative section is the exactly the shape of the guitar. So start by drawing this. Next add the thicknesses of the above and that is your next offset line.


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Ken

Roll UF glue on the parts on all surfaces except show faces and load the layup inside two al slats and the silicone blanket goes on the inside. Then a third al so all slide well. Silicone doesnt slide well.


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Ken

I've never tried laminate sides, but why the heating blanket? Don't the veneers bend without it?

Yes the bend fine. I use heat to cure the glue and evap water quickly.


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Ken

Uni-Bond 800 is a urea formaldehyde glue and as Ken said, it is water based, or rather it cleans up with water.

That is one testosterone laden laminator Ken. Very manly!!

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

Actually I made it so I wouldn't have to struggle so much. The old one required two people to keep everything straight and lined up.


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Ken