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What is your order in making a wood rosette? Do you cut the rosette to fit the channel or do you cut the channel to fit the rosette? What's the thinking behind the order? Thanks.

I make the rosette first and then along with what ever purflings that I intend to use I trial fit these pieces into the channel as I very slowly widen the channel until I can press everything into place.

The glue that you intend to use comes into play too. If you intend to use CA be sure to shellac the end grain of the top around the channel to avoid staining. Also if using CA a nice press fit of all the parts is what you want.

If you are using Titebond, which is what I use, a slightly less tight fit is desirable in as much as the Titebond joint needs about .005" and since it is water based the wood(s) will swell a bit too.

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Ann Arbor Guitars

Also there are some great rosette toots that OLFers did available here: http://luthiersforum.com/forum/viewtopic.php?f=10117&t=17905

Just scroll down to "rosettes" and enjoy.

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Ann Arbor Guitars

I, and my students, inlay the ring first, not worrying too mcuh about how tight it fits. Obviously the closer the better, but its not all that critical here - why, because we are usually adding anywhere from 60-125 thou or more of lines inner and outer to the ring. Then after thats glued in, we route the channels to fit the inner and outer rings, including teflon for shell if required. these channels should fit snug enough to hold everything in, but shouldnt be so tight as the rings are hard to get seated properly - its a fine line, but the Karol rosette jig really shines here - you can add another 2-3 thou to the channel very easily.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Here is a great tip.... (not to brag... it isn't my tip... someone shared this with me as well.)

1) Mic how big your purflings are going to be. Get it as accurate as you can.

2) Go to McMaster Carr and buy that exact size bit

3) cut the the outer dimension of your ring. (remember to always secure the entire ring. I use two platforms and pins)

4) before you move the bit to cut the inside of the ring switch to the soundboard. Leaving the router in the EXACT SAME location cut your purfling channel

5) Cut the inside of the ring.

6) Again don't move the location of the router bit and switch back to the soundboard and cut for the inner purfling ring.

7) Remove any material between the purfling rings

Presto... perfect fit.

I then use LMI white glue to glue everything up.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

THAT is a really cool way Brock .. unfortunately for me, rarely are any of my rosettes the same size with the same purf design - I would need a drawer full of custom bits.

if I were doing something like this all the time though - three routers is the way to go - one for each of the rings (or one with two pin settings is maybe better, saves one router and bit/ setup), and one for the waste in the channel ... or a CNC machine !!!!

Ahh..... and with this post I hit the 2000 club ... the pinnacle .. BRW. Time to stop and smell the rosewood.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Yeah, if everyone is different it can yeild a drawer full of bits, but most of mine have the same inner and outer pufling scheme.

Regarding reproducing them, what I did was took a piece of Lexan and drilled a pin hole in it, then when I am cutting a rosette I put that on the guide pin and plunge it into the lexan at the various reference points (outer ring, inner ring, sound hole etc.). Then if I want to reproduce a past design I just set the bit to plunge in the holes.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

I use a disc cutter to cut out the wooden donut and the slot.

I rout out the gap of the slot then glue it in.

Then like Tony I cut the slots for the purfling, but rather than route these I use the disc cutter again.

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My soundclick xx luthier blog xx luthier soundclick

What do you mean by "rout out"?

Mike

I route my channels and dry fit the lines and if too tight open it up some with the Wells/Karol percision router base. If there is shell in the ring then I route the channel first too and dry fit a section with the lines and then cut my shell to fit on my jig and then dry fit the whole ring lines and shell at the same time and level the lines and the glue with CA. Shellaced the channel too. But that's for a simple ring rosette. Haven't done any spanish or wood tile or wide ring rosettes yet.