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Hello, All,
I didn't want to get this questions too far off topic, and it's a genuine builder's question so I'm posting it here. Lance, you can move it if you feel that's appropriate.

I know many of you have done inlay routing with dental bits (my dentist buddy says they should be called "burrs", but that's another matter. To us, they are tiny router bits. Today I was routing with a variety of dental burrs that my buddy generously gave me. The shafts are very small, and require the smaller Dremel collet. My rotary tool (very old) was actually supplied with this smaller collet as well as the usual one.

Here's my problem: I start off routing just fine, but then the bit very gradually climbs the wood being routed, leaving a progressively shallower rout in its path. Obviously, my collet is not holding the burr shank securely, in spite of my efforts to really torque it down. I have not used pliars on the collet nut--only finger pressure as tight as I could make it. Maybe that's part of the problem. It could be worse: I could be going deeper. YIKES!. Thankfully, I am only going shallower. I can fix that--if I can just figure out how to keep the bit/burr from slipping.

Have you inlay specialists run into this problem? If so, is there a simple explanation, such as a dusty collet that lets the shank slip? Further, if any of you ran into simple explanations, what were your simple fixes?

I know many of you use dental burrs, because a number of you have discussed that here. How did you get around this problem? I can't believe I am the only one who has encountered this.

Many thanks,
Patrick

My Dremel's have all come with a "collet nut wrench". I think that finger tight, no matter the relative strength of the fingers in question, just isn't going to get the job done, especially with the smaller diameter bits and small collet.
Pliers are likely to wreck the collet nut.

Suggest that you look for the original wrench [or find a proper size replacement]

Use the locking button and really tighten it securely with a wrench.

I have had to go back and re-tighten after experiencing just what you are talking about.

Mike J

I have used these and I have messed some things up with these and I don't use them anymore. They weren't designed for inlay work. It's worth spending the money to buy the right bits.

_________________
Another day, another dollar.

I've used dental burs for years without a problem. The thing is that there are many kinds of dental burs, and some of them work well while others don't. The ones I use are fairly coarse spiral carbide bits that were in fact designed for inlay work, albeit in teeth rather than wood. I use a high speed dental handpiece designed to work with burs, so I haven't experienced any kind of collet problem.

That said, I tend to use the dental bits for my final "to the line" routing--they don't break as easily as the really small endmills usually sold for inlay, but use use a larger carbide endmill for roughing out. It's just a lot quicker than trying to do the whole thing with a little dental bur.

Dave

+1 - me too. I love them for the final, really delicate work. I use the little wrench that Dremel provides. Finger tight isn't tight enough.

Thanks for all the input, guys. I knew I wouldn't be the only one who has dealt with this problem. My dentist did give me some larger inlay burrs as well as the smaller ones. But it's no problem for me to order some other bits as well, and I do have two collet sizes.

About the collets: Mine are both standard, four-jawed collets. My rotary tool is not a Dremel brand name, it's a Craftsman more than 20 years old. I do have the locking pin on mine, but the tightening nut is round and knurled--rather like a very small drill chuck locking collar. There is no wrench. The larger collet grips really well. This is the first time I've used the smaller collet. I'll take another whack at it later today. If it turns out that I need to buy a new Dremel tool, the hardware store is only two blocks away.

Thanks again to all,
Patrick

Leave the dremel tool in the hardware store as it's not good for inlay work. They just have too much runout for a tight inlay. A cheap die grinder will be the best for the money.

Mark, I appreciate the suggestion, but what do you use for router base attachment on yours?

Okay, Guys, I really hate to admit this, but it's too darn funny, so you're all welcome to have a laugh at my expense: Guess what I found in recesses of my rotary tool box this afternoon? A wrench. Once having found the wrench, it suddenly became obvious that the two small flats in the collet nut fit the wrench very well. Hmmmmm. Using a larger, flat bottomed, undercutting inlay bit to hog out, and a small straight sided one to get close to the edges, the routing went very quickly and smoothly. These tiny little sharp inside corners are a real pain to cut and pick out with x-acto, though, aren't they?
Thanks again to all.
Patrick

Stu mac has one and i believe John Hall sells one as well that fits a standard die grinder. Mine is to be clamped down in a duplicarver.