Best glue for bent lamination

[smorris]

As the new dining table progresses along I'm at the point I need to start thinking about the skirt.

Normally I have no problem thinking about skirts... but I digress.

Now the issue. I've built the forms and have my laminations cut, 1/8" Ash which will bend onto a 23" radius, to later be veneered with Mahogany. Question I have is what is the best glue for this. I asked while I was at Woodcraft today and while they can usually help me I just got crickets on this question. If I recall, titebond isn't the best because it is a bit elastic and I would want something more rigid. Epoxy should work but pot life is pretty short and I have to assemble 6 layers. Anybody have some experience they would like to share, I'd certainly appreciate it.

Side note, I find as I have been working on this project that Mahogany is a joy to work with. Stable, hard but machines well if you pay attention to the grain. And unlike when I work with Padauk, I don't have to hazmat up before I start working with it.

[gsmittle]

I seem to recall Nahm using Titebond for bent lamination. Of course, he makes the form a hair smaller in radius to allow for the springback. Not to mention Nahm probably has elves watching over the whole operation.

Would liquid hide glue work? Or how about the Titebond vacuum laminate glue? Or am I totally off base?

g.

[just started]

Seems to me David Marks used Gorilla glue quite a bit for bent glue-ups.

[Jim Frye]

Bender Says...

Opps, I can't say what Bender says. What glue you use for bent laminations depends on the installation. If the lamination is secured at the ends and has little stress on the bend itself, then most any glue will work. However, if the lamination is freestanding or unsupported at the ends, you have to be aware of joint creep. If the lamination is capable of moving, then you should use a glue that will not creep under load. In this instance, epoxy or resourcinol glue which cure hard would be the adhesive of choice.

[drumpriest]

Not gorilla glue...Plastic resin glue, such as weldwood from DAP or Unibond 800. These glues dry harder than yellow glue, and therefore have less spring back for you.

Thin laminates and these glues are about all you can do to reduce the spring back, other than choice of species and cut of grain.

[cabinetman]

TB II or III will work just fine for bent laminations. Actually any PVA or aliphatic resin glue (white or yellow) will work, but they don't give much open time. You have to be all set up and ready to go. No real time to scrounge up more clamps. Using a urea formaldehyde glue like Keith suggested will give more open time, and provide a good bond.
.

[atgcpaul]

Use PVA if you can do the glueup quickly and the apron will be secured in
such a way that lamination creep can't happen. Otherwise, use a urea
formaldehyde glue like DAP Weldwood or Unibond which will result in no creep
and a super long open time.

You can find DAP at smaller hardware stores like Ace (and Amazon). It's cheaper than
Unibond and can probably be found locally. I've used it twice. The first time
I had great success. The second time, I think it had expired (although it's a
powder) because it wouldn't mix well with water. I bought the bottle one
year earlier and stored in my garage before use. Maybe I messed up. It was
more like sand in water. I ended up buying a container of UltraCat from
veneersupplies.com which worked well. However, they don't sell small bottles
any more. 1 pound of powder will probably be enough for you to finish your
lamination.

If you are ready to glue up, track down a tub of the DAP and test out a small
portion. If it mixes (there are always a few lumps) well (like pancake syrup)
and sets solid, it's good to go, go for it. If it's sandy in texture, return it and
buy the Unibond 800. I've seen Unibond in action and it mixes very well.
The demonstrator stored unused portions of the Unibond liquid in the fridge
to extend its life.


Paul

[smorris]

Thanks for the info everybody, I think I go get some DAP and give that a try.

[drumpriest]

Weldwood is probably the better choice in plastic resin glues for bent wood lamination anyway, as it uses water which will help in getting the bend into your veneers. When doing veneer to substrate jobs on flat panels Unibond is better as it won't cause the veneer to curl as much.

[L. D. Jeffries]

A good article in the Oct issue of "Popular Woodworking" about glue. The different types and what they are best used for, the pro's and con's of each kind. Check it out, there is one expressly for bent laminations. Page 51, "undewrstanding Glues, Part 2"