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There has to be something seriously wrong with Dremel if Harbor Freight's mini grinder is of higher quality than them. Can anyone explain why Dremel has such a lousy quality?

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I use a modified Stew-Mac base to hold an NSK Presto high speed (and very quiet) air powered dental handpiece. They're not cheap, and they won't use standard 1/8" shank bits. But what they will use is much cheaper dental burs. They turn at 320,000 rpm and have virtually zero runout. The high speed makes the NSK ignore any grain issues--it won't follow a soft line in the grain like a slower speed router will. And finally, the NSK doesn't require any oil, so the air that comes out of the tip (and blows the dust away) is dry and oil free. Very nice setup.

I also have one of John Hall's routers, and it's very nice. I use it for hogging out material (with the 1/8" shank bits that the NSK won't handle), but it's loud. All in all, pneumatic seems to be the way to go for me.

Dave

PS--I also use the NSK in a CNC machine for cutting pearl--works great!

Thanks for posting, Dave. I don't do much inlay work, but this sounds like the set-up I'll want if I start building steel strings. At 320,000 rpm (wow! really?), I wonder if the tool is really quiet, or just not noticeably loud. 320,000 rpm would be about 5 kHz.
Two flutes might generate 11 kHz. Multiple flutes=?. We've all lost most of our hearing above 20kHz, but I'm careful about what I have left.

I don't own a Foredom tool, but I used them a lot when I built bicycles. They were pretty handy for grinding brass filets. I imagine they'd be much too slow for inlay work. I'd prefer my laminate trimmer even for rosettes. (A Wells-Karol gizmo is on my list. At present, the Paracho version of the popsicle stick and Exacto knife works well enough.)

I agree that the run-out on Dremels is hopelessly bad. I haven't tried Todd's upgrade mods. What hasn't been mentioned is what happens when you put a spiral cut bit in a machine with run-out. I spent an embarrassing number of months wondering why my Dremel sometimes cut an hourglass channel, sometimes a barrel shaped channel, sometimes neither.

The NSK is almost exactly dentist's drill loud--a normal tone of voice will be heard easily above the noise from the NSK. Way quieter than a die grinder. I wear hearing protection for darned near everything I do in the shop, but the NSK doesn't require it. And yes, it is really running at 300+K RPM. The cutters are spiral end mills--probably 4 flute from what they look like.

The one downside to the NSK is that it spins so fast that you'll burn the wood if you're not careful. At 320K, feed rate should be a lot faster than I normally route freehand to get a proper chip cut rate. That said, you can buy dental burs that work great for inlay from Lasko Diamond and others for a fraction of the price of a small carbide endmill, and it can do better work. The NSK handpiece has ceramic bearings (that allow the high RPM) that keep the runout basically unmeasurable, and the requirements on the compressor are just a fraction in terms of PSI and CFM of what a die grinder requires. The last big benefit that John Hall's pneumatic die grinder machines share is that these pneumatic tools are so much lighter and smaller than electric motor based machines--even lighter and smaller than a Foredom handpiece. Very maneuverable.

All in all, I would recommend getting one of John's routers and giving higher speed pneumatic routing a try (with hearing protection--it's fairly loud), and then deciding whether the significant additional cost of an NSK is worth trying or not. John's machines are quite reasonably priced and work WAY better than a Dremel as long as you have a compressor that can handle the load. I consider the NSK to be the next step up, but it comes at three times the price.

As a sidenote--You mention being careful about the hearing you have left--I've spent most of my life working hard to protect my hearing. I always wear hearing protection when I'm using power tools or a shop vac. I've always worn hearing protection when I run a lawn mower or ride a motorcycle. But about a year ago, I got T-Boned in my car and the side airbag went off in my left ear. Never stopped to think about hearing protection when driving a car....Everything through my left ear sounds like a kazoo now. The sound is there, as is most of the frequency response, but it's really nasty distorted. Airbags are probably good things all in all, but when one goes off in your ear, it's about like having an M-80 inside of headphones. Very violent.

Dave

If you wear hearing protection on a motorcycle, how do you hear important things like another car coming at you, children, etc?

Back on topic, can someone recommend me a burr that I can use to smooth out carvings I have made with a fluted burr? I tried the sanding drum burr but all it really does is carve slower, yet its still no more smooth than the fluted burr in terms of surface evenness. I would have to do it by hand but it's really tedious, and the surface is too tight for a palm sander to get into.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Brief off topic, but important--it's actually easier to hear what's going on around you when you take away the wind noise. A set of custom fit earplugs is great whether on a bike or in the shop.

Dave

I guess you guys have better luck with the HF mini grinder then I had. Mine started spitting out oil and the runout vibration loosened up the bit. Went with a Sioux 5979A. I'm still not wild about the noise and will probably eventually get a Foredom for inlay. I have a couple of Dremels that are 10 years old and still hanging in there.

HF is so iffy in quality . You can make a muffler for the exhaust hose , I take a paper towel and fold it in 3 then tape one end on the exhaust hose and the intake hose . this helps for noise and anything that spits out .

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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

Thanks John, I'll give that go. Now you got anything for my noisy A compressor?