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I used my Dremel tool with the attachment that lets it cut circles when I put the inlay on my top. It worked great, even though it seems to lack precision, it cut perfectly. But I'm wondering about which way to go around with it now. The inlay piece cut nice, and the inside edge of the top. But the outside had some chipping. The wood WAS a bit chippy, but I'm wondering if it was because I didn't pay any attention at all as to my direction. I'd rather not have that on this one.

Do you always climb cut the edge that you want to be finished? I used to climb cut on the mill all the time, but I didn't even think about it for this.

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Why be normal?

Here's my take on that. You got a router bit that's 1/16" or smaller moving at around 20,000 rpm. I really
don't think it makes much difference which direction you are going, with respect to grain. Also, if trying to maintain
a downhill cut on the grain you would have to start/stop the cut and lift/move the router to do this....not something
I would choose to do.
For me it's always slow and steady from under the fretboard around in one continuous pass. It can be incrementally
deeper on several passes if needed. A sharp bit, no play in the routing fixture and no run out in the spindle. A laminate
trimmer is my preferred tool for this job but I'm sure lots of people use a dremel... maybe taking a little at a time with multiple
passes.

If you are using a rotating router bit there is always the potential for it to tear out some fibres rather than cleanly cut them. This is most likely to occur at the portion of the circle when the cutter is running in the same direction as the grain - which is at the east and west poles of the circle (if we say that the fingerboard is the north pole). You can minimize this if you initially cut the outer and inner line using a gramil tool. Then use your routing tool (laminate trimmer or Dremel) to hog out the space between the lines that the gramil cut, sneaking up slowly to the line.

I agree with both Ken and Mark on all of what they mentioned.

I recommend watching the video on this page of the StewMac website, for all of the little things that can help with the use of a Dremel for this job:

https://www.stewmac.com/luthier-tools-a ... g-jig.html

I have always cut rosette channels by starting at the centerline at the fretboard side of the rosette and making a single full-depth pass all the way around going counter clockwise. Once I get back to the start point, I reverse direction and go all the way back around clockwise. The edges always come out clean and I've never had tear out on various types of spruce and redwood. I use downcut bits from StewMac in a Bosch Colt.

While I don't worry about cut direction for routing rosette channels, I do pay close attention to direction when routing off top and back overhangs and when routing purfling channels to go with the binding.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Yeah, for sure, those tasks are where you need to be very aware of cut direction. I always go from widest to narrowest, in relation to the center line. Half of those cuts are climb cuts. Here is another relevant StewMac guide (partway down the page):

https://www.stewmac.com/articles-and-vi ... rings.html

I did mine like the video, but the cutter was smaller than the viola purfling I had, so I had to cut the rosette side first, recut the slot until it fit. I cut the rosette most of the way through and flipped it. That tape idea looks easier, especially for the sound hole, that didn't come out clean.

That's some wicked tape. What is it?

I just trimmed my edge with a fingerplane and a file, and would have never guessed to go climb cut on half and conventional cut on the rest.

Thanks for that link, Don

One of the things I found strange was that I could feel the hard winter grain while cutting.

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Why be normal?

I have found that for the wider channels on rosette the cleanest way to do it is to be sure and do a climb cut for each edge so that using a bit smaller than the desired width of the channel you would cut counterclockwise for the outer margin and clockwise for the inner margin.

I have seen some very small irregularities after final leveling where the cut passes into end grain if the edge is routed with a non-climb cut

For a really narrow ring, say 0.062 where the bit is the same size as the purfling I usually go counterclockwise, and have not had any big issues but you could also do those in two passes with a 1/32" bit if issues are seen.

I always shellac the top before routing, use a sharp bit, and if you use thin CA for a glue never forget to shellac the channels first!!!!!

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It's not what you don't know that hurts you, it's what you do know that's wrong.

A Dremel will never give a completely smooth cut. They just aren't up to the task.

I don't like a Dremel for the job, either. I currently use a Bosch Colt in a Bishop Cochran base. That works great. I recently bought a Foredom and the StewMac handpiece, which fits into the StewMac Dremel router base. That is a pretty good setup for inlay and notching the sides for back braces. I might experiment with the Foredom for a rosette, but the Bosch Colt does a very nice job. No need to switch.

Splurging for a BC base for one of my 310s was one of the best things I ever did. Don't know why I didn't do it sooner. I agree, ditch the Dremel for rosettes.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

In my view, the sole advantage that the Dremel (with the required StewMac rosette tools, like the router base and circle attachment) has over a laminate trimmer placed in the Bishop Cochran router base is visibility. It can be a bit hard to maneuver your head, and enough light, to see what is what around the bit with the Bishop Cochran base. But the Bishop Cochran base has such precise adjustments that you really don't need as much easy visual confirmation of what is going on down there. You can dial in the settings before placing it on the rotation pin, and trust that it is in the right place, only needing a short (strained) look to make sure you didn't mess up the settings.

John at Blues Creek sells a pneumatic die grinder with a base for a reasonable price. It has a 1/8" collet. It's a nice tool and does a very good job. I've been using one to do inlay (and any precise free-hand routing) for some years now , I run it with a small compressor.

For rosettes I use a DW 611 laminate trimmer with a Precise-Bits collet on a Wells-Karol base which also works very well.

I think the problem with the Dremels (I have two) is that they have too much runout. Just not a precise enough tool.

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Steve Smith
"Music is what feelings sound like"

I have this Dremel, and some other tool that I got at Woodcraft for hardly anything in a sale bundle. It seems to me that the cheap one is more solid, It's a Force. Yeah, I never heard of it either. But I used it to cut the fancy inlay on my 5 String Viola, and cutting them by freehand that came out surprisingly well. I tried the Dremel, and it bounced around. The problem with the Force is that it didn't come with anything, and naturally the threads on the end are different, so it doesn't fit anything.

That said, I got 1.1 mm cutters for 1.25 mm purfling, EXPECTING wobble, and they cut 1.1 or less, even on the Dremel. So for the rosette I had to move the cutter about .5 mm to fit the viola purfling in. Not an easy feat without an adjusting screw. I still do the outside purfling on violins with a knife.

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Why be normal?

I've heard others report that they have been able to do just fine with Dremel or Dremel clones. That's good if they work. The Dremels I have are too sloppy, however, they are very useful for drilling small holes or running cutoff wheels.

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Steve Smith
"Music is what feelings sound like"

I am thinking about getting something like a trimmer in the future. Cutting the slot for the truss rod is a pain by hand. I guess that you COULD always use the right sized boards for laminated necks.

A Dremel would be useless to cut a truss rod, or carbon fiber slot. Would a laminate trimmer do the job? Too late to suggest it for my birthday or Father's Day. But I have to have things on my list for Christmas too. If I buy everything I need, there isn't anything left.

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Why be normal?

A laminate trimmer is big enough to cut a truss rod slot, no problem. A router table is my preferred method, but a laminate trimmer in an appropriate base will work. You will need an edge guide and a steady hand, and take a larger number of shallow passes.

I use a laminate trimmer to rout any slots in the neck blank. It's my second step after making the scarf cut. I use a trimmer mounted in a router table (https://www.rockler.com/trim-router-table) that I attach to my workbench using countersunk machine screws and T-nuts in the workbench. For either truss rods or carbon fiber rods, the depth of cut and location of cut needn't be precise, so the fence of the inexpensive table is fine and virtually any trim router will work. (You do want to make SURE that the top of the truss rod or carbon fiber rod will be lower than the surface for the fretboard.) The width of cut matters more. Using a ¼" bit works for truss rods, using a ⅛" bit works for carbon fiber rods (cutting two slots for two ⅛" x ¼" rods). The ⅛" slots can be a bit tight, so a slight movement of the fence for a second set of passes deals with the issue. I use an upcut bit and two passes for all slots. It works well.

I’ve had success using a Dremel to rout rosettes but I think it’s simply because I lucked into a “good” one without much runout. I’ve seen the less-than-ideal results friends get with their Dremels. So I think the “good” ones are the exception rather than the rule.

Even with a “good” one the lack of power is a limitation. A laminate trimmer is a way better idea.

I have one permanently mounted in a small router table for truss rod slots, but I’ve also hand-held one to mill slots plenty of times. Perfect size for this job.

Hi Ken,
William Cumpiano shows a method for cutting a rosette channel using an exacto blade stuck through a Popsicle stick to score the edges and a chisel to remove the wood in between. I'm sure you have the skills to use this method with good results.
If you do decide to get a trimmer, you might be able to find an older Rockwell 64 or one of its variants ( different model#'s, colors, bases, and also manufacturers (PC309)) I have bought them for $15-35. They were marketed as a compact non professional home craft item (similar to the Dewalt 611) so you can sometimes find them in "like new" condition (I have found a few of them in their original boxes) They do have some of the nice features of the PC 310's and 690's in the adjustment of the base and can be used with a two handled base or the compact base the 309 comes with. Both bases offer excellent visibility of the cut and can take replacement sub bases of your own devising.
You can often find them on eBay, but be selective of what you find. Like any 50 year old used tool avoid those that appear abused and beat up and wait until you see one that is complete and clean and otherwise in good shape (and reasonably priced). When I do get one the first thing I do is unscrew the top, slide out the switch and grease the top bearing with lithium grease and then work some lithium grease into the bottom bearing around the collet just as P.M.
There are plenty of other trimmers out there and most work well enough (but avoid Harbor Freight routers) but of the many types I own or have used the 64's are my favorite.