purfling - - - full depth?

[peter havriluk]

I'd like to ask another question, this time about installing purfling at the side/binding intersection and at the top/binding intersection. LMI sells purfling which can be installed at full depth, so that the binding at the bottom rests on a strip of purfling that covers the relief in the side, and the same can be done with the purfling between the binding and the top. This technique seems to offer an advantage in cutting the binding channel, as there is only one channel being cut, instead of that one channel plus two smaller channels for the purfling if the purfling is 3/32" deep, for example. Is using the full-depth purfling routine, just one way of installing purfling? I'm trying to avoid work that should not be attempted without a lot of experience. Learning is good but I want to manage the ascent up the learning curve. I've seen comments from others about using full-depth purfling behind translucent bindings, and I can understand the need for full depth purfling there, but my intent is to use wood bindings.

Thanks, folks.

[ken cierp]

Basically the reason there are two channel steps it to prevent you from cutting off the top from the kerfing/rim which can and does happen. This is more of a problem with the standard triangular kerfing. Reverse Rounded kerfing is much more forgiving in this regard since it is full width and has the reinforcement ribbon on the inside of the instrument.

[Bob Matthews]

Ken is correct about the concern of cutting off the top, I like my binding channel to be just slightly less than the thickness of the sides so that when it's cut, you hardly see any of the linings. The top purfling channel is then cut separately.

Regarding the purling at the sides, I laminate the purfling to the binding before I bend them and then cut the channels to the depth of the binding + the purfling minus a few thousandths to allow me to scrape the tops of the bindings flush with the top or back.

I think 2mm is well thick enough for bindings (too thick in some cases) and to add a full depth purfling to this is asking for trouble imo.

Bob

[peter havriluk]

Ken, Bob:

Thank you very much for your replies. All makes sense to me, in hindsight, but it would have been impossible for me to think of those answers without experience. New respect for thin bindings when I have a need to respect the triangular 'regular' kerfing pre-installed in this kit project of mine.

[John Parchem]

I built my first classical guitars with full depth purflings. I only had one had one strip so there was a lot more kerfed lining left. It made the operation a lot easier. It was not my choice to do it that way. It was the purifying shipped with the LMI kit.