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I am getting ready to bind an OM with a venetian cutaway. I will either bend some rosewood or use tortoise binding. I want to have a purfing line along the bottom of the binding and miter it at the butt wedge. The purfling I intend to use is 0.060" W/B/W wood fiber.

I assume that I need to bend the purfling first so that it doesn't "kink" around the horn of the cut away. If I use tortoise, should I glue the purfling onto the binding? Should I bend the purfling by heating it? Should I wet it first? Should I use Supersoft II? Should I use plastic purfling and is there a source for it?

Any advise would be appreciated...

My opinion may vary with other builders but I find it simpler to keep side purfling as a separate unit from my binding. While gluing side purfling to your binding seems to makes it a single bend to do both, the fact is that you can simply stack and tape the purfling between your bindings as you bend them. To my train of thought gluing your side purfling to your bindings prior to bending and fitting severely limits the margin of error for fitting your binding as well as limits the margin of error for fitting purfling miter joints. If you make the binding and purfling one unit and you under cut the miter at the end graft, you then have to make up another set. If you treat them independently the purfling allows a great deal of leeway. As it can be shape adjusted fairly easily.

Plastic and or fishpaper (black) and maple (white) will work in this case.

JMPO

I am 100% with Michael on this. I just finished binding an OLF SJ where I used .03" brazilian rosewood pins for rim and back perflings. I debated about first gluing the pins to my eucalyptus bindings, but I decided it would be more work to glue the pins to the bindings and struggle with the miters at the end graft than to just do them separately. If you have a fox style bender, I'd definately recommend this approach. Like Michael, I install my end graft, use CA to get the ends of all my miters glued in place, then install perflings and bindings all at once. I tape and use CA.

I bent bindings and perflings at the same time. The four rim/side perflings were laid on their sides between a couple of binding strips. The two pins used for the back perfling were stacked flat and laid between two more binding strips. Eveything was then taped together using low tack masking tape and bent at the same time in my bender. Worked flawlessly.

Ken

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Okay,
It sounds like that if I use wood binding, it is best to bend the purfling at the same time as the binding, but not glue the purfling to the binding first. What if I use plastic binding? Do I need to pre-bend the (wood fiber) purfling to get it around the cutaway without "kinking"? ...and if so, what's the best way?

hech any guitar with a waist smaller than 3" radius should be be bent, and of course any cutaway has to be bent. you can get away with bending most purflings to about a 3" radius dry and cold. less than that expect the purfling to snap into. plastic you can get away with more.

Kinking is not the worry Snapping happens as soon as the purfling reaches its max elastisity.

Kinking is usually caused when bending binding that is not properly supported. To get a kink the outer laminates have to separate from the inner allowing the inner laminate to bend differently than the outer. That is when purfling kinks. When purfling reaches its max bending point it cracks. On rare occasions the outer piece will stay intact and you see a kink but most times if a crack happens it is clean through.