BYO: Best glue for laminating backs & sides?

Craig Bumgarner

Yeah, that makes sense, a layer of cardboard on either side of the laminate to soak up moisture. If the part is clamped in the mold, then getting air to circulate is a problem. The cardboard would act like a moisture sponge.

CB

Powerfibers

I have never made a guitar, but have made tens of bamboo fly rods. They are a bear to glue up, dealing with tiny .025" thick triangular sections. I learned a lot about glue along the way though.
From what I researched on guitar building, hot hide glue would be best, but the bottled stuff is no better than TiteBond from what I hear.
These are the non-epoxy glues that I have used....

Resorcinol is a great and easy to use glue, but will give purple lines at the seams if not perfectly applied to perfect joints.

Weldwood (the DAP brand powered glue) is very good also, and it is similar to URAC 185 in it's thinness and strength. Urac is the best, but it is tough to measure up and not worth it for what you need.

If you are trying TiteBond, I would recommend giving TiteBond II a shot. It is a much stronger and superior glue to the original formula. Also, always remember to buy fresh stock when buying bottled glue.

If you really feel crazy, try Gorilla Glue, a great polyurethane glue. Be careful though, as it is a mess! Also, you will need to get the wood slightly damp before applying as it uses the moisture in the wood to sure. This stuff is like liquid nails.

Hate epoxies, and I will not use them. The fumes alone are enough to stay away from them. Also, you need to really get good stuff to make it worth while, and large quantities of Epon or some Shell epoxy is not worth it for simple laminiates. Plus, epoxies really need to be heat cured for best application. Their rubbery quality maybe not a good thing for sound applications, not sure.


Good luck, Bob

bill raymond

I don't think I'd use Titebond II. It being "stronger" is questionable, and all of the glues that have been mentioned will be "strong" enough. In addition, though it may be a good glue, there has been some anecdotal evidence reported on the Musical Instrument Makers Forum of less than ideal results using Titebond II. Gorilla brand polyurethane glue is OK, but rather expensive for what it is. ProBond polyurethane glue seems preferred by luthiers who use PU glue. Be very careful with PU glue, as it will glue your laminae to the mold, given the chance! It also stains your fingers if you get any on them.

You can't see in the photo of my gluing mold, but I've sized the cauls so that I can put 4 thicknesses of veneer (or other packing piece) above the laminae. This helps spread the clamping pressure evenly and provides for a semi-absorbent layer to help wick moisture away from the drying glue.

Powerfibers

Interesting Bill, about the TBII. When used in rods that flex under great pressure, it works great, while the regular Titebond delaminates easily. Again, I am not a luthier, so maybe under not flexing situations, it is good stuff. I agree the PU is probably overkill, and it does not do well if it gets on the skin as you mention.

Craig Bumgarner

Was going through some of these BYO posts and thought I would update this one.

I used Weldwood Plastic Resin Glue for laminating the back and sides on my last two builds and I like it much better than Titebond. PRG hydrates the wood much less and sets up hard overnight. Titebond takes weeks to harden up and I doubt it ever gets as hard as PRG. PRG is more thixotropic, so it is much less messy in use. Course there is that pesky formaldehyde issue with PRG, be careful in mixing and use. Once set up, I don't think there is much danger.

Craig

Bones

Hi Craig,

Are you still going with this glue? What about epoxy (I know, toxic)?

Also, what thickness veneers are you using? Was thinking of using a bit thicker material on the outside to allow for a bit of sanding to take care of any unevenness.

Thanks

Peter Davies

Hi Craig,
I haven't tried laminating myself but it might be worth a look at Benoit de Bretagne's site.
There are several build blogs of Selmer type guitars that are laminated, e.g. -
http://www.benoit-de-bretagne.com/phpBB ... c&start=30
It looks like they used Titebond in some photos.
(Also some Castellucia renovations)
All the best,
Pete

Craig Bumgarner

Bones wrote:

Hi Craig,

Are you still going with this glue? What about epoxy (I know, toxic)?

Actually, I switched to epoxy for laminating last fall and like it better all around. No hydration, hard cure. Longer working time, thinner glue line. I don't worry too much about the toxicity, I only use it for this and I'm careful to use gloves and not get it on me, work neat, good cleanup and all that. I use WEST System epoxy.

Also, what thickness veneers are you using? Was thinking of using a bit thicker material on the outside to allow for a bit of sanding to take care of any unevenness.

I use what I think is the standard thickness these days., 1/42", .022", 4 layers. I have used 1/30" veneers, three layers, they work very nice, but I have only been able to find them occasionally. If you know of a source lot me know.

Bones

I don't have a source for the veneers since I have not had the guts to try it yet. I've only done solid sides. I have a friend who does laminated sides on classicals and flat tops (with solid backs) so I'll ask him if he knows a source for thicker veneers. He does the laminated sides since they are stronger (less prone to a crack) and also they come out more fair than bending solid wood (even on a side bending machine).

Which type of West Systems do you use? I think they have thicker or thin versions??

Thanks

Craig Bumgarner

Peter,

My French is terrible, and it gets even more complicated because the French terms for guitar parts, tools, etc. are all different (bindings = nets, braces = dams), not to mention a love of slang in internet forums, but what I am getting when I try to read this is some discussion of Titebond and lots of discussion of epoxy. It sounds like the two major posters in this section, Birdie and the OP, Oldman, are using both at some point in the b/s laminating operation. Can you tells what's what, I can't. Perhaps using Titebond to glue the veneer halves together and epoxy to laminate???

I personally, however, use Titebond only to glue the halves of the veneer together before laminating. For laminating, WEST System epoxy is superior in every way to Titebond. Most important for me is no hydration of the veneers like Titebond causes. Much less warping and expansion of the veneers which shrink back six months later after being finshed, ugh! Weldwood PRG, hide glue and any glue using water as a vehicle will do this as well, though perhaps not to the same degree as Titebond.

I use the epoxy measuring pumps which dispense the proper mixing ratio per pump, so I don't have to weight anything. I've used a lot of epoxy in my day job, boat building and repair, so I'm pretty comfortable with it. I avoided it initially because I thought it might be too messy for guitar work, but in fact, it is just the opposite, it is cleaner and neater to use than Titebond or Weldwood PRG.

That said, I use a fair amount of Titebond most everywhere else. I use Titebond II where I plan to heat the glue joint later, like gluing purflings to bindings before heat bending. I use epoxy for laminating veneers for b/s, gluing the head block to the sides, and gluing the fingerboard to the neck shaft. Most everywhere else, I use regular old Titebond. I use hide glue occasionally, especially where I (or the next generation) might want to get something apart later, like a glued neck/body joint or gluing a fingerboard to a guitar top.

Bones,

I'm using WEST 105 resin and 205 hardener. I don't know if that is "thick" or "thin", but the viscosity and working time are fine for laminating. These are the standard resins we use all the time in the boatyard where I work.

Craig