PV glue for bent laminated parts of furniture?

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Hi guys.

I want to make a piece that needs some parts to be bent laminated.
Any of you have atempted to make bent laminated parts for a piece of furniture? What glue did you use? I'have a video where they suggest to use an epoxy two component glue (powder+resin) and warn against using polivinylic glue due to its elasticity.

Have you used PV glue? what results dit it gave to you?

Any suggestion will be appreciated
 
Toni, I have used PVA on bent lam, and while I can't prove it they did seem to have more spring back (the elasticity). This could psychological on my part since I don't have way to do 2 glue ups and compare. In any case I switched to plastic resin glue (Weldwood) which has some other advantages (and disadvantages). The drawback: it cures slowly, so it's in the clamps at least overnight....longer in cool temps. Squeeze out can cause nasty cuts. You also have to go through the exercise of mixing for application. The advantages: It dries rock hard (it's a sandable glue) and has a longer open time, allowing you a more relaxed assembly time for clamping. It also has no glue creep like PVAs, that can be important on some pieces, less so on others.
 
I've done quite a bit of bentwood lamination with a variety of woods. PVA (yellow) glue will cause more springback because it's relatively soft. I've seen it on a couple of things I made but it wasn't a killer due to the type of project. I experimented with plastic resin glue on the same pieces to see how much difference it made and there was no springback. That convinced me to use nothing but plastic resin glue for any bentwood work I do.
 
Weird timing on this one.

I have been watching a video series on FWW and Michael Fortune is building a garden chair using bent lamination's. He uses PVA and when he takes the glue up out of the form, he adds a clamp back over the top for another 24 hours. Not a lot of tension, just enough to keep it's shape. He feels the water induced from the glue causes the spring back issue. From what I have seen so far of the video, he could be right.

I also watched another set of videos doing bent lams and the plastic resin was used. I dries dark and the user didn't like the look as he was using a light spices of wood

Update, I went and looked, the user that didn't like the Weldwood changed to Unibond 800. It comes in a couple shades and is easier to match the wood species being used
 
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Ok guys thanks a lot. Fred, thanks a lot for the link to Welwood in Amazon in this way I can get it here, and shipping is not so expensive. I just placed an order.

Thanks again to all.
 
That's a good point about the plastic resin glue drying dark, I forgot about that. You can get agents to lighten the color but they aren't exactly down at the box store. I got some from Veneer Supplies with some glue I bought from them.
 
That's a good point about the plastic resin glue drying dark, I forgot about that. You can get agents to lighten the color but they aren't exactly down at the box store. I got some from Veneer Supplies with some glue I bought from them.

How dark? I will be using a padauk which is quite dark and reddish, or maybe oak.
 
I doubt it will be a problem with paduak. On the oak it's possible you might not be happy with it, though it didn't bother me. But my use was on rockers for a chair. I have a fair amount of the lightener left (the glue is long gone). I can mail you a few ounces if you want. It's just a white powder, looking all the world like flour. But for the actual color of the glue, I would call it a light brown.
 
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Here are a couple pix of a cherry glue-lam using plastic resin glue. Messy, but no creep. Glue lines nearly invisible after the cherry sun-tanned for a few hours.

DSCN0027 (Custom).JPGDSCN0032 (Custom).JPG
 
I doubt it will be a problem with paduak. On the oak it's possible you might not be happy with it, though it didn't bother me. But my use was on rockers for a chair. I have a fair amount of the lightener left (the glue is long gone). I can mail you a few ounces if you want. It's just a white powder, looking all the world like flour. But for the actual color of the glue, I would call it a light brown.

Thanks a lot for the offer Fred, but no need of it I've already ordered a couple of cans from Amazon, if you had to send it to me it would cost 40$ at least, while amazon has better deals only 10$, Besides I guess that one could dye it if needed, after some trials though.

Here are a couple pix of a cherry glue-lam using plastic resin glue. Messy, but no creep. Glue lines nearly invisible after the cherry sun-tanned for a few hours.

Thanks for the pics Jim. You are right the glue lines are almost invisible, I may make a trial first just in case.

View attachment 89705View attachment 89706
 
I concur with the plastic resin glue many have recommended. When I tried PVA glue, the residual spring in the wood very gradually led to creep of the PVA glue, and very slow relaxation of the bend.

The ultra-cat sold by Veneer Supplies is generic plastic resin - seems identical to the DAP plastic resin i have also used. The lightener they sell appears to be powdered zinc oxide (the white component of the old fashioned sun blocks that people wore on their noses). If you can get powdered zinc oxide, I would use it to lighten whatever plastic resin. Veneer supplies gave me permission to reprint their color chart on my web page on glues... check the middle of the page at www.solowoodworker.com/wood/glue.html under veneering. That is the best picture I have seen of the natural color of plastic resin glue, same thing with a little white, and same with more white. I used it with a curly maple tabletop, and the glue line "disappeared."


CooverTables.JPG
 
I used Weldwood, too, but I need to offer one little tidbit: scrape off any squeeze-out with something hard and unimportant. The glue dries rock hard and will destroy a delicate chisel or plane edge. Better yet, sand the stuff off.
 
I used Weldwood, too, but I need to offer one little tidbit: scrape off any squeeze-out with something hard and unimportant. The glue dries rock hard and will destroy a delicate chisel or plane edge. Better yet, sand the stuff off.

I trim the edges with the table saw. I have never sensed any degradation to the carbide tip saw blade, and the multiple layers can usually use a little straightening in addition to removing the glue. The saw leaves them perfectly even. Be sure to use eye protection, since the sawdust includes shards of the glue.
 
I trim the edges with the table saw. I have never sensed any degradation to the carbide tip saw blade, and the multiple layers can usually use a little straightening in addition to removing the glue. The saw leaves them perfectly even. Be sure to use eye protection, since the sawdust includes shards of the glue.

and wear gloves when handling it before cleaning it off (I've always sawn it off as well, sometimes on the bandsaw). But cuts from that stuff are really nasty and painful. No gloves while actually on the power tools, obviously.
 
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