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Just ripped off a whole bunch of rope binding, maple and walnut for a weissenborn gtr.. I had a few pieces fall apart . which I reglued with fish glue I am using reg titebond to laminate the walnut and maple strips.. My question is , what glue are you using that will not break down when bent under heat ?? I have not bent any pieces yet , some strips are uneven and need to be rethicknessed. I will also be adding a .022 veneer to each edge before bending thanks !

I use titebond III

Yep - TB3 worked for me too

Tnx guys tb 3

It will be much easier to bend if you add the veneer to one edge only before bending. Adding the second edge to the outside after it is installed isn't usually difficult.
I have made "miniature" rope binding by splitting herringbone down the middle. If you turn it 90 degrees from usual it makes an alternating B/W block pattern.

tNX CLAY and others . have lots of walnut veneer .022, and have laminated both sides before bending. . Test run today on the side bender

Hi Ernie,
I've never tried using a side bender for purflings made up of small blocks of wood. I worry that the heat might make them come apart. The titebond 3 might be a good way to go so I will be interested in hearing about your experience with it.

I bend herringbone right on the edge of my bending mold. No heat, just tape. If it feels stiff I put a couple drops of water on it and slowly coax it into shape.
Unless your bends are radical you might try cutting a curved channel in something and see if you can slowly coax it in. Key word there is slowly.

Sure beats all the problems a bender and heat can throw into the procedure.

T

I made another set of rope binding for ukes, The colour scheme is green poplar . maple and walnut. The bends are tight . FWIW One is supposed to use dry heat. to bend the tight curves on ukes , as I have read. Will wait an see. We are off to Lowes for TB3, an sightseing happy labour day! Clay , spending to day with son . I will post the binding results here when I can wife will take pics I hope. Thanks everyone .

I made rope binding with regular Titebond and it was a real pain to bend so I didn't do it again. Maybe I'll try again with TB3 sometime

Let's see that Weissenborn when you're finished!!

Update quine is good natured, titebond does not work for rope binding . I spent at least 2 or more hrs to get the green poplar/ maple /walnut rope binding bent as a rosette for a 72mm circle or 2 7/8in (uke). It broke twice and was reglued. .The inner and outer rings both broke, and had to be reglued several times. Dont try this at home unless there is adult supervision. TB3 on thurs for new rope binding . PS I used med heat #4 on the generic electric /alum/vertical bender

When I think of purflings, I consider them to be similar to braces in that as the width is squared the stiffness is cubed. For that reason I have in the past split herringbone binding down the middle if I wanted to install it in a rosette (assuming it wasn't pre-formed as a rosette). Also wetting the pieces slightly softens the glue and allows the small lengths of the "bone" to move some which means it bends more like the single outside strand they are attached to. I bound a uke in "half herringbone" which gave the appearance of a delicate rope binding around the edge.
It might be worth gluing up the "rope" with a water soluble glue and a purfling line on one side of it with a water proof glue. Then by wetting it enough to soften the glue between the blocks they might slip past each other slightly and allow it to make tight bends (similar to what splitting herringbone will do). You could install it with a loose purfling line on the outside edge of the rope and glue them both in at the same time. I haven't tried it yet, so I'm not speaking from experience, other than what I have done with other types of purfles.

I laminated 2 veneer strips of cypress with tb3 to a core of maple / walnut rope binding made with titebond. Will resaw and see if it can be bent

Ernie—

A few thoughts from when I experimented with building my own herringbone purfling:

The more glued layers you try to bend at once, the harder it will be. And using real wood, as opposed to the black fiber used in commercially available purfling, makes it even harder, because real wood is more fragile. I found it easier to separately bend each half of the herringbone pattern (one layer of outer veneer plus one side of the chevron pattern) and then glue it up after bending. You need one layer of veneer to keep the diagonal middle from falling apart, but any more layers makes it super hard to bend.

Bending wood is more about compressing the wood at the inside of the bend than stretching the wood on the outside of the bend. Wood compresses easier than it stretches.

Other than compressing and stretching, bending purfling can happen by allowing the layers to slip along the glue lines holding those layers together. But is the glue letting you do that? Does it soften when heated, then re-adhere after bending and cooling? It depends on the glue chosen.

All in all, I think you are asking a lot of the wood if you are putting veneer layers on both sides of the rope, then trying to bend the whole sandwich. But, experiments on the ground give the best answers.

Good luck!

Tnx don, going to thin the sandwiched veneer on BS before bending, trying to do an easy bend, the weissie headstock.