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I recently began building a violin kit that I purchased from Grizzly Industrial. The kit looked pretty great, but since it was my first kit I didn't want to dive right in and risk messing anything up. To practice cutting my purfling grooves I made some templates out of 3/4" pine. I used a 1.5 mm bit, as the instructions said, but the purfling still appears to be too small for the groove. Does the purfling expand once glued in? Or is my problem simply a mistake in cutting the grooves?

I don't build violins, but it sounds like your cutting too large of a binding channel. Depending on what material you are using for your binding, you might see some expansion. For instance, if your purfling is wood and you use a glue like Titebond, LMI white glue, or hide, you will see swelling of both the binding and the plate. So, sometimes a semi loose fit will be great. Don't expect swelling to fix large gaps though.

I don't know what you are using to route the binding, but Dremel style tools can have significant amounts of runout that will widen cuts more than you want. You could always go the purist route and cut the channel with a gramil. Stewmac has the one traditionally used for violins I believe.

Aaron

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Aaron Craig

I would go the hand route. Buy a purfling cutter. Cutting a purfling groove on a pre carved thin violin top is almost difficult to do. You don't have the body sides like you do on a guitar to guide the dremel based cutter. I have used the hand cutter and the time it takes to set up a dremel cutter you would have been done with the purfling cutter. Besides using a dremel to do this is sacrilege in the violin makers world. Mike

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Another day, another dollar.

I build violins and fiddles. I have used the Dremel/edge guide method. Be sure to use the same size bit as the purfling. If you are getting a sloppy(loose) fit, it will show up no matter what glue you use. The purfling should slip into the groove with a fit that is just short of being snug. When I glue in the purfling, I haul the mail knowing that the moisture in the glue will start swelling the spruce or maple right now. I would measure the purfling and be sure that I had the right size bit. Don't trust the info. in the kit. They could be wrong. The purfling that I use is always 1.3mm and I always measure it before using it to be sure. I don't want to ruin a top because I didn't take a little time to make sure it was right. But back to the question. My guess is that your purfling is not 1.5mm, but is really 1.3mm. To check your fit, route a purfling groove into a piece of straight scrap and check the fit. When the purfling is bent it is hard to tell if your fit is perfect.If I can help you at all, Just ask. By the way, my first fiddle was a kit from Stewmac. Pals, Vic.