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I'm trying to see if there is a a better solution for the cutting of the rosette and doing inlay work. Rather than using the standard stew Mac precision base, and rosette attachment, or is this basically the best thing out there at the moment? I look forward to everyone's reply.

Jim

There are higher end tools that use a laminate trimmer for the router. Follow this link to the Wells/Karol Precison Micro adjust router base http://wellsguitars.com/Available_Instruments/Luthier_Tools.html. A bit higher end is the Bishop Cochran router base http://bishopcochran.com/Bosch%20Colt.html.

Many make their own version of the Wells Karol. You could also try a Popsicle stick and an exacto blade (preferred by classical builders)

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http://www.Harvestmoonguitars.com

I use a Porter Cable PC 310 (no longer in production) with a Wells/Karol jig that I picked up from Sylvan many years ago.

The Wells/Karol is fantastic. I just sold mine after many years of happy use in order to upgrade to the Cochran.

Popsicle stick and exacto knife? My mind went right to it. I have a Dremel and a cheap circle cutter. Also have a Dremel router type holder with circle cutter. Never tried the router thingy. But have been delaying cutting a rosette channel.


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I use a Proxxion router. I have and did use lam routers but the Proxxion with an adjustable base I made is the cats meow. The ability to use multi fluted 1/8th" router bits is important to me. Never any tearout or chipping.

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Michael F Smith
Goat Rock Ukulele
http://goatrockukulele.com

The Wells/Karol with a laminate trimmer is an excellent choice if you want to be free to use an endless array of rosette sizes. My focus is on traditional Martin designs and I'm considering switching to a couple of fly cutter/disc type rosette cutters to hopefully save some time. Does anyone have any info on making these?

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Good judgement comes from experience. Experience comes from poor judgement.

I'd say that anything you use is good as long as you master the tool. I use the Stew-Mac jig because I can make any size rosette I like, including an over 6" Stella.

The regular General circle cutters work fine. Buy a couple spare blades - or some 1/4" square tool steel, and grind them to the desired width. A flat bottom grind worked fine for me.

To make a guard, I used a piece of 1/8" polycarbonate wrapped around into a circle and secured with a few pop rivets. It was never 'required', as I was always careful to tighten everything down, but better safe than sorry.

If you are looking for something fancier, it would likely be easier/cheaper to buy LMI's fancy rosette cutter than to make your own (unless you're a machinist).

(I guess this isn't any help AFA making your own disk type cutter)

Before you make one or buy one, just know that these cutters, even with new sharp cutters, will tear out wood when going across the grain on the bottom of the rosette channel. As long as you can live with an uneven channel bottom across the grain (on 2 ends = about half the channel bottom) then go for it. Once the rosette is glued in this these flaws are hidden. But the wood glue is acting as a filler on part of the bottom, for which it is not designed to do - unless its epoxy of something. Will the rosette come up later if hide, white, or yellow glue is used? Likely not.

Hmm, I was thinking that they would do a better job. Collings and Wayne Henderson use them-- do they have a secret?

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Good judgement comes from experience. Experience comes from poor judgement.

Interesting. I never had that issue using a simple hardware store circle cutter. It cut nice clean flat bottom channels, cleaner than a router actually. I ground the cutter myself. I'd suspect something else is wrong with the setup if that kind of tear out is happening, or perhaps it's just better to use a cheap circle cutter than a fancy rosette cutter thing...

To be clear, I am talking about the Drill Press Rosette Cutter as sold by LMI here:
https://www.lmii.com/products/tools-ser ... tte-cutter

As I said, after the rosette is glued in you can't see the flaws. Have you ever seen the bottom Colling's or Henderson's rosette channels? Likely not. If you happen to catch in-focus close-up pictures you'll see it. I talked to LMI about this issue some time ago and they said "Yep, that's the way it is. That's why we use a router."

I understand that this fly wheel cutter was invented by John Greven. Regardless, John Greven does use one. The Spring 2014 #117 Guild of American Lutherie quarterly magazine has a long article about John Greven's methods. Page 12 has 3 pictures of this cutter. Picture #26 shows Greven's rosette channel clearly. It has lots of tear out across the grain on the bottom of the channels. This looks exactly like my experience and other pictures I have seen. The users of these cutters simply accept the tear out for what I can see and understand.

So you are just talking about tear out on the bottom of the channel, correct?

I am trying to come up with some ideas to make these myself , but probably out of a plywood disk.

Note when using fly cutters;
BEWARE THE CUTTER!!!

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Pat

Yes, that is what I said. The bottom of the channel going across the grain will be rough with ridges. A router will be clean, but the LMI drill press cutter will not, if that matters to you.

Wells Karol jig with a Bosch Colt laminate trimmer here. Works perfectly every time.

A plywood disk fly cutter sounds extremely dangerous, besides being too flimsy to hold tolerances.

For sure. It sounds to me like even aluminum is problematic.

I have used the Stew-Mac jig with a foredom tool and it has worked well for me... no complaints...

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

Popsicle stick method works incredibly well. The real advantage with it is when you make rosettes that are all the same width. You don't have to mess with adjusting the cutter, it's permanently set.
That and a little Stanley hand router is all you really need.

Well, the plywood disk idea is basically to make the outside round sort of like the lmi cutter and not having a spinning arm swinging around trying to get me! Securing the bit and chuck is another issue.

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Pat

wayne henderson uses a custom made fly cutter . He gifted me one made by Don Wilson. It is similar to the one LMI sells but the cutters are ground for the rosettes he uses. Can do a rosette in 10 seconds once they are set up. I love mine.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Cutting out a rosette cavity is one thing and cutting out an inlay cavity is another.
Just a note about the Wells/ Karol base; Shouldn't it just be the called Karol base?

I agree Chris. My understanding is that this was 100% designed by Tony Karol who in the spirit of sharing posted a picture and info most likely on the MIMF forum. How the "Wells" got associated with this has escaped my logic. Perhaps it's experiences like this that has stopped him and others from posting many other ideas.

I have lmi rosette cutter and love it. Never spent more than 5 minutes cutting rosette including tightening the chuck.
And it does not tear out wood anywhere.


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I use a Foredom in a Bishop Cochran base with a downcut spiral bit for inlay and rosettes with excellent results. It does have a larger than ideal minimum radius for circle cutting though... I've had to find alternatives when doing small instruments like ukes.