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I glue the purfling onto the binding, one stick at a time, then bend 5 of them in the Fox bender @ 250 F.
What glue(s) is (are) considered best practice these days for bending in the Fox Bender Use Case?

I've asked several manufacturers about it, and Franklin (TiteBond_) had the most compelling recommendation, for TiteBond Extend (Original).

A builder friend told me his last bend (with Titebond III) was not optimal, and the binding glue line wanted to come apart after bending. Franklin's ASTM data suggested the after-heat adhesion is poor with TBIII. Granted the "high heat" was only 150 F.

JJ said in his laminated binding video that he used "Gorilla Glue Non-Foaming Clear" for laminating, calling it PU glue- it is not PU. I just glued one up with GG and the glue actually stuck (somewhat) to my UHMW polyethylene clamping fixture- I had to peel the binding off the jig with razor blades

I had used the LMI Instrument Makers Glue with high success- those happy days are gone.

I'm interested in what you have to say.

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Measure Twice,

Karl Borum

I use TB3 exclusively for that task, and only for that task. Once in a bloated blue moon I’ll have some delam which is readily sorted with the clothes iron.

Having said that, I realize that just this morning I forgot that I use TB3 exclusively for that task, and used TBOG and it worked out fine. Lucky me.

Please remind me that I use TB3 exclusively for that ask, lol.

I've always used TB3, no problems.

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Jim Watts
http://jameswattsguitars.com

TB3 here too.

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Steve Smith
"Music is what feelings sound like"

TB3 as well here. Just don't get crazy with the water. I try to use no water as this is what causes the delamination.

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https://www.instagram.com/fostinoguitars/
https://www.facebook.com/PuraVidaUkuleles/

I've never glued purfling to individual binding strips. I glue up a 2" to 3" wide "log" with veneers and binding material at the same time with Weldwood plastic resin glue. Joint one edge and rip binding/purfling strips with a .025" slitting saw.

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Stay with the happy people.
--Reynolds Large

Lately I have used thin CA glue. Clamp the binding to the purfling first, then wick it in. Holds up to bending fine.


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For the glue file; the Gorilla Clear "hybrid" adhesive is fully dry, its rubbery and gummy (but dry) and will not sand off by hand. Ran it through the thickness sander and salvaged the piece. It may well be good for a binding log, but definitely not for a one-up piece. I would have avoided a lot of work if I would have had patience and waited for my test piece to dry.... Might be great for fishing waders

_________________
Measure Twice,

Karl Borum

Super thin CA works well. Purfling usually comes in .09 to .11 inch width, so we left the binding at .08-.09 inches (slightly under the purfling), then used an HDPE feather-board-like fixture to align and hold the laminates for glue-up (one side of purfling and binding flush, and a bit of a ledge on the other to keep the wick of the glue away from the fence side of the fixture).

A pass or two through the drum sander cleaned things up, with some though given to ensuring that any fiber-laden purfling preceded the binding through the sander to minimize rolled fiber edges, and some cedar or soft maple dummy material mixed in with the tape-cross-banded purfled binding strips generated a wider package for bending that did not tend to favor top caul or cutaway ram lean to left or right. The super-thin BSI glue seemed to hold up beautifully to heat when well attached to the binding and avoids the heat release issue common to thermoplastic adhesives.

Much appreciated when building up complex purfling stacks (e.g., 20B-10W-10R-10W-10G-10W-10B)... much easier than trying to goop and corral separate strips with low-tack or extremely high tack liquid glues. A reduction in the 'juggling cooked spaghetti' ... great party game, but not much fun for the luthier.

An old photo of the fixture (all I have ready at hand):



Note: If binding in something soft or porous (e.g., SA mahogany, spruces, paulownia) CA staining of the wood due to wicking is a real possibility - two coats of 1 lb cut dewaxed shellac sealer (super blonde/Platina) will seal things up and the CA will stick well after a very light pass with maroon ScotchBrite to knock off any excess. For the normal run of binding woods and purfling stacks, not an issue.

If in doubt, try a sample CA glue-up and prep, then bake at 260-280 deg F for a bit, followed by inspection. Adjust adhesive accordingly.

CA sets up when it hits an alkaline surface. Many woods such as walnut, are acid, and CA can set slowly on them. I like to rub a bit of baking soda on the surface, wiping away the excess. Enough is left in the pores to get the CA kicking over.

TB3-never had a problem.

I’ve always used TB3 with no issues. I donmt use a lot of moisture when I bend though.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I have used original and titebond 3. I tape two bindings together purfling to purfling when bending. When the glue softens the purflings are still clamped to the bindings.

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http://www.Harvestmoonguitars.com

What johmparchem said.

I dealt with the binding set I accidentally used TB OG on and it was a PITA. The bindings and purfling stuck to the paper, stuck to each other, it was most irritating.

TB3 is far superior for that task…