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Hey guys,

I'm still working on #1 and have run into some issues with the rosette and the rosette channel.

My original idea was to take some of the excess wood that was cut away from the back and use it to form a rosette. I knew that I wouldn't be able to cut a full sized ring out, but I planned to piece it together so that each piece had a wide end and a narrow end and I would lay them out to form a circle.

I tried using a Dremel with a router attachment to cut it out, but the results have been less than satisfactory.

Here's an idea I had. Let me know if it sounds like a plausible solution:

I have a coffee grinder that's not being used for anything. Stay with me. I break the mahogany into tiny pieces, stick them in the grinder, whizz it up till it's a mahogany powder, then combine the wood powder and glue (CA or Elmer's) and make a paste that I can fill in the channel with. Let it dry for a couple of days and sand smooth.

I could be out of my mind, but I think this could work. Bear in mind I haven't used CA glue in many years, but I have a brand new bottle.


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Try it in a test channel on some scrap first.

I think you'll find that it will be very different in color and character to the back and sides.

Then put some lacquer over it to see if you like it.

I have a feeling that if you like the look of MDF or particle board, it'll make a great rosette.

_________________
Old growth, shmold growth!

Will it work, yes.
Will you like the look, well,
maybe...

Personally it's not a look id want for a rosette. But who knows you may like it

What exactly went wrong with your original rosette? Many people make them in that fashion. In my opinion it would be better to get some feedback on what went wrong there and try to get that method down.

If your plan is to make composite rosette then I would suggest using a router or something that will make larger chips and then use some long set epoxy to fill the channel and then embed the chips into the epoxy before it sets. You could tint the epoxy black or a complimentary color which might give you an interesting look. But that would take some experimenting to get the exact effect you were going after. But I think it will still resemble particle board when you are done.

I'm with ZekeM, figure out what went wrong in the first place and stick to your original plan.

Bob

What went wrong was that the Dremel was not very consistent and the result looks chewed up and pretty crappy in general.


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What model Dremel and what cutting bit did you use, and at what speed?

I just touched up a rosette, going from this:
To this:
Using this:

I used the Dremel 3000 rotary tool, and the Stew-Mac 1/16th inch downcut spiral router bit at about 25000RPM's

No fuzz, clean channel, good fit.

_________________
Old growth, shmold growth!

BTW, it occurs to me too that for your particle rosette to work, the channel edges MUST be super clean and even as well, otherwise it WILL look horrible no matter how good the material matrix looks.

If you're having trouble getting a clean channel, then you must develop a workable method before going further, as has been suggested.

_________________
Old growth, shmold growth!

Bob was right. It looks like particle board... I guess I'm going to try and cut very small pieces and glue them into place.


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Practice with the dremel. I use a dremel for my rosettes, as do many.
Try to make the rosette thicker than you need. Then instead of cutting all the way through, creep up on the dimension you need. Making sure that you are only cutting in one direction. Make your last pass a nice smooth conventional cut. This should give you a nice clean edge without any of the chatter you sometimes get with the dremel due to runout. Once you have done that you can sand or plane the back of the piece until you have reached the depth of the cut you made and the rosette will drop right out.

Justin,

It sounds like one of 2 things (or both) are happening.

1. You are trying to cut too much at one time and with the wrong bit.

2. You don't have a good solid guide (or are trying to cut it by hand).


You should be only taking very small cuts at one time and when starting the first cut only go about 1/3 the depth. Lower your bit and make another pass and do that until you reach the depth you want. If you are cutting a channel wider than your bit then only take about 1/16" at a time. That will keep the bit from grabbing too much wood. Cutting too deep will also allow your bit to flex and veer off the intended line which will bind the bit and cause burning or chipping. I would suggest ONLY using down spiral bits since they will give you a cleaner edge with less sanding.

Don't cut anything free hand... Always use a jig or guide to make sure you cut accurate lines. Freehanding it will almost always end up in a slip of some sort that will chew things up pretty badly.

Hope that helps,
Bob

I also use a dremel on my rosettes and when I start having problems it's because the bit is dull. A sharp bit, small depth of cut and a dremel should work. It also helps to shellac the area first to cut down on some tear out. Just a couple of thoughts. You can save the grinder for breaking up your shellac flakes so they dissolve faster.

Or actual coffee.
If you're like me, you won't be able to sleep or let it go until it's satisfactory.

_________________
Old growth, shmold growth!

Thanks for the replies guys. I may have been trying to cut out too much at a time.

As for the idea of using wood from the back for the rosette, I tried cutting some small pieces and I wasn't happy with the dry fit. So I've ordered a herringbone rosette from LMI and it should be here in about. 5 days. I'll try the original idea on #2.


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Quick question about thicknessing after the rosette is glued in:

Do I need a specialty tool like a scraper? Or can I use something like a very small (3") plane?


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Block plane or/and scraper, both fiendishly sharp. Sharp is everything.

If you still have issues getting the dremel method to work, consider the Wells/Karol jig and a laminate trimmer, such as the Bosch Colt. Use high quality downcut router bits like the ones StewMac sells. This method works great for me. I get a perfect rosette every time.

http://www.wellsguitars.com/Available_I ... Tools.html
http://www.stewmac.com/shop/Tools/Routi ... =3&xsr=306

I personally use my scrapers most of the time unless I am squaring up the face or edge of a board. I have found doing fine work like shaving bindings down with a plane has a tendency to get into the surrounding wood, I feel I have more control using a scraper. I also use my scrapers backwards from most people. Instead of pushing them away from me I pull them toward me. By pulling them I can see exactly where it is cutting by watching the shavings so I am not scraping places I don't want. I also place a work light behind what I am scraping so I can see where the scraper is making contact. It is really helpful on things like bindings so you know you are scraping square to the top of the binding (another reason I pull the scraper toward me rather than pushing it)

Buy yourself a good set and a burnisher. Learn how to sharpen them and keep them sharp. If you learn how to sharpen them correctly it takes less than a minute to burnish a fresh edge on to keep them cutting. I also use my scrapers instead of sandpaper most of the time which keeps me from breathing dust and is much easier to clean up. I would say that my scrapers are probably my #1 used tools.

Cheers,
Bob

Justin, while I will confess that I now use my drum sander to sand the rosette level to the top, but before that I used a scraper and sand paper. I agree with Bob on regarding a scraper, and depending on how much of the rosette is above the top, I would worry about using a plane. Scapers are not very expensive, and they are very useful for a variety of tasks; for example, bringing the binding and purfling level to the top and sides or in final shaping of the neck.

There are some good videos on YouTube that show the jigs and how they work for cutting rosette tiles.
I cut mine on a band saw with a jig I made. Others use a drill press with a sanding drum for the inside radius and a clamp with a pivot for the outside then to a miter box for the angle. The tiles are especially easy to make with wood.

What you need to do here is to spend big bucks and get a Bishop-Cochran router base and a Bosch Colt laminate trimmer. All in with the small radius guide and the router, you are looking at about $400-$425. You will get nice, clean rosette channels and a kick a$$ looking router base.
There are very few problems that can not be solved by throwing large sums of money at them.

Alternatively, you could buy a pack of utility knife blades for $0.99 and use a piece of scrap with a hole drilled in one end, like this:


While it does not cost as much as my first option, it will set you back about a buck or less if you have blades on hand already, it will get the job done very nicely and it will not break the bank. The downside is, you wont have a killer CNC machined, red anodized aluminum router base. I think the choice is simple.

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http://www.CostaGuitars.com
PMoMC

Hope you are applying a couple of coats of lacquer or shellac over the area before you rout. Let it dry overnight.

Haans,

I applied one coat and let it dry overnight and there was some tear out. So in future I'll be applying more coats prior to routing. Pretty discouraged at this point. Hopefully the rosette I ordered from LMI will look good. Should be here on Tuesday.


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Don't be discouraged, Justin. It's a big learning curve. I just replaced a whole rosette on a half lacquered guitar. Just buffed it yesterday and looks good.
You must make sure the lacquer is good and dry on the seal coats, not just the surface. I normally rub in 2-3 coats with a paper towel. I used to use a dremel, and actually have 5-6 of them, some you can actually wiggle the shaft. Not too good. The Proxxon works a lot better, although nothing will work better unless you have good sharp bits, especially if you are using a softer spruce like Engelmann. Going very slow is the other important part, and as mentioned, sneaking up on the final cut. I do rout my full depth, but never go more than half the diameter of the bit. A dial caliper helps too. It's tough to get the right slop in the slot, and I usually find that I have to rout just a tiny, tiny bit more in certain areas like 4 o'clock and 10 o'clock. Sometimes just another pass in those areas does it, or sometimes I just lean on it a bit in those areas if I can't get the rings in on a trial fit.
I always use white glue on wood and Weldon 16 on celluloid and wet the slot just before installing. Never cut out the soundhole till you are absolutely satisfied with the rosette.
Here is the whole rosette replacement...

Justin, the others have given you lots of good tips. You might also be having some issues with your blank rattling around, not well-anchored to your workboard. Lots of little details can contribute to the problems. Our generous fellow correspondent, Hesh, has just posted a link to his tutorials. One of them is a very well-explained demonstration of rosette making--including working with the dremel tool. I just read it yesterday and thought it was VERY informative. He has many other excellent tutorials on the same site. Take a look:

http://www.lenaweelutherie.info/page6/page6.html

Patrick