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As promised here is part II of how I make and install a wooden rosette.

This process starts for me with a top that has been joined and thicknessed but not thicknessed to it's final thickness yet. This top is currently in the .130 range.

I have selected the best side to be facing up/out and located the center of the sound hole and installed the 3/16" Stew-Mac router base pin. In addition I have clamped the top in two places that will not interfere with the rotation of the router/Dremel base.



My sound hole is going to be 4" in diameter and I want my rosette to start 1/8" from the sound hole. Here we see the marks for where I want to route the top for the rosette.



If you recall the rosette will be flanked on both sides by a .032ish b/Indian rosewood/b purfling strip. This means that the routed channel will have to be large enough for the rosette and the purfling. The rosette is also cut at the top center and a small segment is removed so that it can flex a bit to be fitted into the rosette channel. This area, where the rosette and purfling will not meet will be covered up by the fret board extension and not show.



Our rosette and purfling are very close to .080 thick which means that we want to route our channel less then .080 deep so that the rosette, when installed, is proud of the top and can be scraped or sanded flush with the top.



I have adjusted the router base to cut less than .080 deep and will do a trial cut, again under the fret board extension area, to check the depth. I also try to make the trial cuts well inside the lines on the top of where I want the rosette located. More on this in a minute.



Here we see that the depth of the cut is .066 which will work fine.



The depth of the channel is being measured using the end of the dial caliper and then reading the results.



With our depth now set and a double check of all the fittings on the router base to make sure that they are tight we are ready to begin out cut. I prefer to cut the first pass well within the lines just in case I do get some tear-out. Although this has not happened to me yet this first pass is removing more wood then any of the subsequent passes will. The cut is made in a clockwise direction with light pressure to keep the router base moving at all times at a slow rate.



To be continued.......

Once the first cut is made we now have our depth established and the depth settings on the router/Dremel base will not be changed. I do however check to make sure everything is snug with each pass - just to be sure......

From this point we will simply move the cut in toward the center a slight amount each time until the channel kisses the inner mark for the rosette.



After each and every pass I remove the router base from the center pin and vacuum up the dust. The reason for this besides that fact that its tough to be me..... is that if the router base is riding on dust the depth of the cut will not be consistent. A consistent depth for the entire rosette channel will help ensure a good glue bond when the rosette and purfling is glued.



The process is repeated until we have our channel cut to the inner and outer lines and then the rosette is trial fitted. We can see here that the rosette, with a little push, fits the channel nicely. Now I continue to expand the channel outward trial fitting after every pass until the rosette and purflings will fit.



I measure and cut both an inner and an outer purfling strip and trial fit them into their respective locations.







The channel is expanded a slight amount at a time until I can nicely press, with minimal pressure, the rosette and purflings into place. I am not looking for a tight fit although you may wish to do so if you are using thin CA to glue the rosette into place. I prefer Titebond and use the tendency that water based glues have to swell wood to my advantage. With this said one additional advantage of Titebond will be detailed shortly.



With the rosette and purfling strips now trial/dry fitted the router base pin is removed.



To be continued.........

Now it's time to glue in our rosette and purfling strips.

A bead of Titebond is placed in the rosette channel. I use a small artist's brush to distribute the Titebond evenly in the channel and up the sides of the channel.



Next the rosette and purfling strips are pressed into place. Note the line on the rosette on the right indicating the center of the book-match - I try to line this up with the center of the top.



Now the excess squeeze-out is cleaned up with a paper towel.



With everything pressed firmly into place and the excess glue wiped up I cover the rosette in waxed paper.



And then I add a flat board and some weight for clamping pressure.



What you will see next is completely optional but I wanted to offer this method because it works great for me - every single time. My goal is to have a gapless rosette and I have found that some of the properties of Titebond can be used to greatly add to a positive outcome.

So...... next I note the time and I am looking to wait 30 minutes from when I clamped the rosette in place.



While we are waiting I wanted to mention that you may also use scrapers or even a ROS to sand the rosette flush with the top.

My preferred method is to use my thickness sander and 120 grit paper so I set that up while I am waiting.





To be continued.........

Hesh, is your top two bookmatched pieces? If so wouldn't the bookmatched face(s) be the 'outside' everytime?

How time flies........



The reason that I wait 30 minutes before removing the weight from the rosette is that I want to run it through my thickness sander while some of the glue is still damp........ 30 minutes seems to be enough time to glue the rosette in place while still leaving some of the glue damp enough so that the dust generated by the thickness sander will automatically fill any gaps. This is probably the 8th time that I have installed a rosette this way and I have yet to have a single gap.

Here we see our rosette with the weights removed sitting proud of the top.



I immediately place the rosette under the drum of the thickness sander and slowly lower the drum while turning the drum by hand. It's best to do this with the thickness sander unplugged and not in your boxers..........





When I can hear the drum just slightly contacting the proud rosette I am ready to start thickness sanding the rosette and top.

You can see that this early pass leaves some smearing but you can also see that the the glue is still not completely dry. This, in combination with the swelling effect of water based glues is what closes the gaps.



I never lower my thickness sander more than .005" at once or about 1/8 of a turn on a Performax 10-20. After several passes the results are looking great.



And not a single gap in sight.



Now we have a gapless, installed wood rosette.



Thanks for looking!

Very nice, Hesh. Great detail, as usual.

_________________
Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Where did you get the Black/Brown/Black perf?

Hesh,

Great tutorial, as usual. You've really taken on the tutor role

Do you steam or heat your purfs to bend them? I've been using a little water on them,
but it's not unusual break one- usually just when I'm in the middle of gluing them up

_________________
Gene

Politicians and diapers must be changed often, and for the same reason- Mark Twain

Thanks folks!

Gene these purfs bend very easy by hand, note the photo above of me wrapping them around the channel. I typically never use very thick purfs for a rosette so I only bend them by hand.

Zach these very cool purfs were a present from another OLFer who sent me a care package. He had noticed that I commented that I am not a big fan of seeing white in purfs and sent me something that was perfect for my taste. I believe that they were custom made for him because I have never seen them commercially available.

Nice easy to follow tutorial with excellent pictures, thanks Hesh!

That rosette looks VERY clean and tighly fitted - EXCELLENT WORK!!!

Dave F.

_________________
Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

The Heshmeister.....

Are you happy with your Performax 10-20? I was looking at one the other day and wondered about a dreadnought back going thru it.....

_________________
There is no difference between the man that thinks he can....and the man that thinks he cannot.

Hi Hesh!

Thanks for such a fine tutorial. Your pictures and explanations are very well done.

Would this work when using ablone as rosette? I ask because your subject makes me believe this method is particular to wood.

Thanks, David

It's great seeing your process Hesh Buddy!!!

I think I'm in lust with your sander! What do you think a guy like me and a Performax would it work?

I could make homemade parmesan topping too! YUM!

Thanks Bud!

_________________
Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)

Thank you gentlemen..... and Billy........

Billy you stay away from my sander man - I love my sander and would not part with it for anything..... well maybe enough to buy two of them...... Then I would give one of them to you!

David I don't think that I would recommend running shell through a thickness sander. It probably would be fine with very fine paper like 220 but that kind of defeats the purpose of a thickness sander.

Snig buddy yes I am very happy with my Performax 10-20 Plus sander. I have used it for a couple of years now and I am still finding new things (for me) that I can use it for. It came out of the box very well set-up and all I had to do was verify the accuracy. Since then I check it occasionally, just out of boredom....., and it has remained well calibrated through about 10 guitars that I have used it for.

D*ead plates are no problem and like you I wondered about the accuracy of double-pass sanding (running one side through and turning the top/back around and running the other side through) before I bought this machine. But it works great and I never even get the slight ridge that some people have complained about with 2 pass sanding.

One of the things that I like the most about it is that it is not very big and on wheels. So it's not in my way and stored in a closet when not in use.