Thread: alternative to epoxy

Blokes like Rocker use techniglue from Carbatec on his rockers and "Z" chairs.(its still any epoxy)
I think others use resorcinal glues or Urea Formaldehyde?

Try here!

I've done a bunch of chair parts, 3/4"x42", averaging 8 layers of 1/8" thick. I use Titebond II, and it's worked well for me.

Paul

UF

Used a lot of Urea Formaldehyde (UF 109 brand name) back in Canada. Made hundreds of projects with it from laminated tops to a whole building made from steam bent oak and cold molded ply panels. All the oak ribs were glued with UF 109 and epoxy on the ply panels.

UF 109 has easy clean up, excellent pot life and is very forgiving with mixing ratios when the powder catalyst is used.

If you use the acid catalyst it's an even simpler process to use but you have very little working time. All you do is roll the catalyst on one face and the resin on the other and clamp together. Depending on the temp it can go off real quick.

Urea glues give off a toxic gas (not sure what the skin contact effects are, probaly bad). But the effects are not noticeable in the short time but you end up with cancer 20 years down the track.

PVA

All creep to some extent. So you're going to have to access how much long term forces are going to be in play.

I'm sitting at a 15 + year old table that I made with a 5 layer curved ply skirt. Once you remove the back veneer layer on 1/4" ply it bends like wet noodles so a PVA is more than adequate. But I wouldn't use it with wood that has a lot of spring back (I wouldn't have dreamed of using it on the bend oak ribs for the building no matter what the manufacturer promises).

Over time the risk of delamination isn't worth it to me with a glue that has creep. It's extremely difficult to successfully repair a bent lamination that's delaminating so I make sure the glue is going to be up to it.

Don't know what the toxicity of the new PVAs are though I have read safety data sheets the say they're mildly toxic but without an explantion.

Epoxy

Is the obvious best glue for the job but there's a great deal of toxicity to the skin and breathing with it and it's compounded with the higher than usual amount of mess associated with laying up the bent laminations.

I've watch the effect of poisoning over an 8 hour day of breathing epoxy. The guy I worked with decided to go without his respirator because it was a really hot day. By the end of the day the guy was extremely depressed and down for no apparent reason (and he'd never been like that before), he had absolutely no motivation left. Working time varies depending on what you buy.

I personally prefer the liquid epoxy over the paste version and add fillers as I see fit but YMMV.

Polyurethane

Used it also but I can't say what the long term affects were. It's very easy to use and very forgiving with gaps. There is no creep with it but it's long term strength isn't well known.

It's extremely toxic on the skin and breathing.

Very easy to use; water on one side glue on the other and clamp. Working time is good, for a longer working time don't use water.

great advice, thanks

As an aside, you run the risk of warping the tabletop by veneering one side only due to differential movement of the two timbers. Either that or it'll delaminate. (thats why ply always comes in an odd number of veneers)

Cheers
Michael

Originally Posted by mic-d

(thats why ply always comes in an odd number of veneers)

That's not exactly true. Allword (for one) is two ply veneer. I use it all the time and prefer to any of the others I've used. I've been using it for a number of years without any failures with Allwood.

My 2 cents

Paul

Originally Posted by hcbph

That's not exactly true. Allword (for one) is two ply veneer. I use it all the time and prefer to any of the others I've used. I've been using it for a number of years without any failures with Allwood.

My 2 cents

Paul

You might be misinterpreting what the original poster was asking, or I was... I thought he was talking about laminating up to make a curved part for something. Allwood is a thin 2 ply veneer that is bonded to a stiff substraight such as the afore mentioned curved part. Ideally you should also be using a backing veneer to balance out the part. Which in theory makes up the odd numbers to reduce warpage.

If you try laminating 4 strips to make up a 3/4" thick curved molding... it stands a very good chance of warping and or twisting further down the track. If instead you use an odd number like five the chances of warpage are significantly reduced or completely eliminated. I got caught once years ago and never repeated the expensive mistake again.

Originally Posted by hcbph

That's not exactly true. Allword (for one) is two ply veneer. I use it all the time and prefer to any of the others I've used. I've been using it for a number of years without any failures with Allwood.

My 2 cents

Paul

Are we getting our wires crossed here? I think you are talking about 2 ply veneer (which is probably glued up with grain parallel?) which is glued to a substrate. Or are you talking about a 2ply plywood?
I can only find a handful of references to 2-ply plywood - a flexible ply where the grain of the 2 veneers are parallel and this one:
http://www.stilesmachinery.com/submi...ryFile_274.pdf
where the "2ply" is a composite of a veneer on highdensity fibreboard. I have no idea how they stabilised this unbalanced product???

Cheers
Michael