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I am doing Martin 45 Style binding and looking for a better way. I have done three of these before and am about to do 4 more. It is a real PIA and the biggest issue I had was the thin strips twisting out of place in the sharper curves.

Not the purfling on the guitars top since those stand vertical and as such bend naturally but the purfling on the sides, under the binding, that you have to bend across it’s width if you catch my drift.

I am able to glue the one b/w/b strip to the underside of the Ivoroid binding but then there is poly and a b/w strip. That one is problematic. Sometimes, due to forcing it into the curve, it peals apart and I have to reglue it.

Has anyone done this before and found a good trick to make this easier.

I am using Duco BTW. I will put glue along the rim for about 4in and then struggle to get all the pieces in and tape up as I go.

John, I don’t know if it helps you, and it would add more steps to your process for sure but… I use strips of HDPE as a binding proxy to get all the purfling glued in first, and then the binding comes later. I have a bunch of .060” thick HDPE and can ship you strips to try if you want.



Brad


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That's brilliant Brad, where do you get that stuff?

I love that! It's no wonder you got your picture on the cover of the Rolling Stone

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Hutch

Get the heck off the couch and go build a guitar!!!!

For the purfling under the binding on the sides, I cut the slot for it with a dremel side cutter bit after I install the binding. I think that’s a John Greven trick.

I bought a sheet of it from e-plastics a long time ago for experiments with jigs to make solid lining and double sides. I eventually switched to vacuum for that.

It’s been useful for sure. I think I have your address if you want to try it.

Brad


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That’s the other (and more deserving) Brad.


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Yah man, I would love to try it. Many thanks.

Interesting. That would get the depth perfect too. For these I have to back the pearl up with cotton string. I'm not sure I would trust my hand at that though. Do you happen to have a pic of your setup?

LMI used to carry various sizes of proxy bindings, as well as proxy strips for abalone channels, maybe Allied picked up their remnants?

Do you prebend your binding assembly? It looks straight in the photo.

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Measure Twice,

Karl Borum

It's ivoroid so it doesn't need to be prebent, it bends very easily. It's that lowest b/w purfling on the sides that is the trouble maker because it has to be bent across it's width just like the purfs in your image only they are not glued to the binding.

I don't know if this would fit into your installation process, but maybe. Since I install my side purflings before installing the binding, I pre-bend them. The purflings I buy are typically 0.100 or more wide which doesn't like to bend flat so I rip them down to ~ 0.085" wide on a zero clearance insert (a piece of scrap wood) on the bandsaw. After cleaning them up, I tape them in a sandwich between the bindings for a side and bend them together and they bend nicely with no twists. I know you don't need to bend your bindings but maybe you could come up with another way to sandwich them together and bend all of them at the same time.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

The Dremel bit is called “carving bit 199.” It has a 1/8” shaft, so a 1/4” bronze bushing with a 1/8” id serves as the bearing. I don’t remember where I got the one I have. I didn’t have a guitar at the right stage to give you a photo of it at work, so I had to fake it. One of the beauties of this process is that you can cut right at the line between the binding and the guitar and eliminate any gaps you might have had gluing on the binding. Mine cuts a .040” slot so it is perfect for .040” b/w purfling. You can work the bit on a stone to cut a narrower slot, or make multiple passes to cut a wider one. As I said, I think I learned this from John Greven in an old GAL magazine. I apologize if my memory is incorrect.

I used HDPE strips like Brad showed above beside the tail insert to save space for the purfling.

One more trick: I have used a straight bit and an edge guide on a Dremel base to cut the groove for the top purfling inside the binding after I have glued on the binding. There are plenty of opportunities to screw it up doing it this way, so I don’t do it often.

I have done that several times. It's part of my re-topping technique where you save the original binding drop fitting the top in and then routing out a purf channel to hide the edges. It worked surprisingly well. John Greven used to have a tutorial on his website which sadly is taken down.

John, I almost forgot about this!! I sent you tracking in a PM. Hope it helps.


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S-M sold me a 'proxy' 1/16" thick UHMW strip that gets used when installing the binding proper. After the glue dries, pull the strip and install the purfling in the gap at the bottom of the binding. I've done this many times.

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Peter Havriluk

John, If I am understanding this correctly.... When I do any plastic or wood binding I glue the side purfling to the binding first so I have less strips to deal with at glue-up.
I rip the purfling a little wider than the binding ad glue it on with either tape of binder clips then pass them through the wide belt sander to flush them.

The problem is that it goes in this order:

Guitar top
Binding
Purfling (b/w/b)
Poly (for pearl inlay)
Purfling (b/w)
Rosewood Sides

The top two Binding and purf get glued up as you mentioned, it's the purf under the poly that is free floating and a real PIA to bend in the upper bout curve and the waist as you have to bend it across the wide flat section and it wants to twist and even break apart since it's a b/w purling.

I think Brads trick is going to help a lot because I will at least be able to get the top purfs in first and then only really have to manage that bottom one and the poly.

I bend side purfling on an LMI bending iron with those two LMI purfling rings (for lack of a better word) attached. Do you have those “rings”? I attach them apart about the exact width of the purfling. One of those few things I buy that work exactly as they should.

No. I don't know what these rings are. Do you have a pic?

Huh? I thought after all these years I’d seen it all. I still learn something radically new here. I’ve never seen anyone do anything like that. Love it!


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Here they are slid onto my bender. Got them from LMI but probably pretty easy to make.