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Does anyone know of a source for smallish oval rosettes? I've found the larger ones, but the instrument I want one for will be only about 4 1/2 inches wide at the point the soundhole will be, so I was hoping to find a source for smaller ones. (The instrument is a Greek Tzouras, which is teardrop shaped, and about 7 1/4 inches wide at the widest part, and then narrows to the width of the neck at the neck joint.)

My alternative, if I want to use a pre-made rosette, is to go with a round one intended for a ukelele. But the oval is more traditional. Was wondering if anyone knew of a source.

Thanks!

Dino--

If you can't find something to buy, making your own is really not that hard, if you keep it simple. The John Bogdanovich book is a great resource.

Thanks, Don. I've been reading that the Bogdonovitch book is the one to get. Does he talk about making oval ones? With the circular ones, each section can be the same. And besides, there are a lot of very cool pre-made options available, with mother of pearl, etc. With oval, that's not true, so I guess there's a little more geometry involved. Not that there's anything wrong with that.

But maybe I'd be better off just reading the book before shooting off my mouth and making a fool of myself... And simple might not be a bad thing at all for a first build.

Dino: I agree with Don. Making the rosette is the easy part, cutting an oval mounting rebate is another question.Using tiles makes it harder. Going with a gang of purfling strips makes it easier.
Tom

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A person who has never made a mistake has never made anything!!!

That was my thought exactly. Making the rossette is not going to be teh hard part. I have only done 1 oval sound hole and I couldn't settle on a way to cut the rabbet that matched my skill set and tooling at the time. I ended up binding the hole instead. I'd like to follow you progress in case I ever decide to do another one

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Dino--

To answer your question about the Bogdanovich book, I don't think he talks about ovals.

Here is what I would do if I were you:

First, the way I make rosettes is to cut a set of rosette channels (identical to what will go on the guitar) into a plastic cutting board, but going a bit deeper into the cutting board that you would into the guitar. If you use the right kind of plastic, glue won't stick to it. This allows you to build the rosette in the cutting board, glue it together, let it dry, then later put in the guitar.

So, I think the biggest thing to learn is how to cut an oval rosette channel. Then you can cut identical channels in the cutting board and in the guitar, build the rosette in the cutting board, and Bob's your uncle.

I have no idea how to cut an oval. I am sure someone else here does.

Good luck!

This is my naive take on cutting an oval:

First step is to make a set of templates, one for the soundhole itself, one for each border of the channel. and to include registration holes on the templates to insure they line up. These material for the templates would be the 1/8" or 1/4" aspen/poplar/whatever hobby boards from HD or the like - they're easy to carve. At the end of this step, there would be N templates with oval holes in them (progressively sized). To make these holes, I'd print out the correct sized ovals, and then trace them onto the tempate material using carbon paper. I do a lot of relief carving, and I'm used to working this way.

Second step is to cut the soundhole. The template is registered on the glued up soundboard, using the registration holes, and pinned & clamped. The middle of the hole is easy - it doesn't have to be perfect. Can cut a few holes in the soundboard material with forstner bits, or anything. I would plan to come very close to the edges with chisels/gouges, and then finish up to the line with a round sanding stick, i.e. an appropriately sized dowel with sandpaper glued to it. I've never owned a circle cutter, and a lot of the holes I need to cut for carvings, etc, aren't round, so this is also a familiar thing to do.

The next steps are the trickiest - cutting the channel. The key here is cutting the boundary lines first, using the templates to make sure that I don't cut into wood I want to keep. The cutting itself would be done using a knife with a depth stop, following the template. I'd make the templates such that they came just short of the applicable boundary. (Remember, that the inside and outside boundaries are two different templates, so they're done sequentially.). Once the boundaries are cut, the channel is cut using a 271 router plane, or with a gouge and needle-files (if the channel is too narrow to use the 271 effectively).

Obviously, this wil require some practice to get right!

I think the method could be adapted to working with an electric router as well, but I like to work with handtools, that's what I'm used to, so that's what I'll try first. I think the key, even with an electric router, is making the tempates. They need to be formed correctly, but you can use any way you're comfortable with to cut oval holes. (That's all the templates are...)

Does this make sense? I'd love to hear comments.

I just made a template out of MDF and use a router with a roller bushing. Pretty simple set up if you make sure the MDF template is perfect. THe template has an insert to cut the sound hole and when removed will cut the channel.

Yes, that's exactly the same principle, except without an electric router.

You could do worse than contacting Haans Bentrup on the forum, he made mandolins with oval soundholes and rosettes.
http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=43216

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I've used a couple of different methods. On archtop instruments I've done it more or less like the link in Colin's post; cut the oval soundhole, then use a scribe or marking gauge type tool to mark the rosette channel. Cut the channel by hand, or with a router where practical. For an oval hole in a flat top instrument, I have used a single oversize template. You can then cut both rosette channel and soundhole with different router guide bushings with varying offset distances.

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Rian Gitar og Mandolin