On the "teflon" idea:
One concern may be what the fusing heat will do to it.
I don't think the fusing temp is high enough to melt the Teflon, however, you might end up with a serious curl as it bends around the roller in a heated state. I'm not sure though.

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I thought what I'd do was I'd pretend I was one of those deaf-mutes.

 

for what is worth - the bearings in dremel more designed for side force (as if sharpening something, or using micro cutoff tool), making it very lousy drill.
IMO dremel is a half-ass tool altogether which is not good at anything it does. the only stron point of it is the compactness.
i too use the 50$ HF drill press and find it ok. i'm also very limited in space with room for one machine only so i'm switching from miter saw/table saw/dril pres depending with what i need to work for the moment while the rest live on the shelf.

 

Not Sure how old my 3 Dremel are, but my guess is at least 30 years. And one I only use for drilling PCB's.

All 3 still operate fine and Considering the number of PCB's I make for personal use and others I sell, I must have drilled a Million holes by now with that one dremel.

It has gone through 3 sets of brushes on it. The origional brushes are not even available anymore. I have to file down the ones I get now, so they will fit it.

However, It still Drills Perfectly Without any visable wobble.

Maybe the Newer Models are not great, but mine Sure Are!

Seasons Greetings.....Gary

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I agree with Chemelec. I have two really old ones, one is in my dremel press (model 201) all very very old. That one for for boards only.

I use those two all the time. Never a problem other than dull bits and once I connected the transformer clips backwards, it did drill the holes but it was not easy The one in the press was a battery version I just clip 12 volts on it when I use it.

I am getting a Harbor Freight 4 speed one next to try it $19.95 (normally $40).

NOW, I do have a 5-7 year old dremel that I hate. I makes a lot of noise and has a slight viberation.. The variable switch seems to be warn and I rarley use it.

This is starting to make since.. I thought I just bought a lemon unit when I bought the last dremel. Looks like maybe a quality issue..

 

For drilling pcbs, you really want a very high speed drill. well outside the price ranges you guys are talking. I used to use a delta drill press with a cross sliding vise. it was ok but I broke a fair number of carbide bits. this will happen with most of the lower speed drills. the Dremel has the advantage that it runs at high speed but has huge slop.

I use a Sherline mill now for drilling and haven't broken a single bit yet. it spins at 30K and is pretty accurate. I'll convert it to cnc some day for even better results. I bought it for a song at an auction - around $150.

 

Don't know about the Dremel but my Chinese knock off (cost $20-25) has no slack and runs at 8000 - 2500rpm, continuesly variable, no load. Most of the time I run it at about 3/4 of max, in order to keep the noise down. Have never broke a drill bit.

 

Drilling really does go a lot better at the higher speeds of a dremel, if you can stand the noise. I did originally use my big hundred-pound traditional drill press, but it really doesn't even come close to spinning fast enough; I had to go through the board quite slowly to avoid breaking bits, and it never left clean holes.

By the way, Rolf, I saw the current model of the craftsman drill press at Sears the other day, the one you were talking about. Just like most of their rotary tool stuff, it is basically just a re-branded version of the actual Dremel stuff - and in this case it seems to be exactly the same as the (good version) dremel model 220 that I have! Hopefully the craftsman version doesn't get "updated" to the piece of junk that Dremel has now replaced the previous model 220 with...

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most of the small "dremel" type units start out good but aren't really engineered for the long run. You should see the run-out increase over time.

good point on the quality issue, evan. there is just no comparison between the 3K rpm holes and those made at 30K.

 

Just replace the brushes and oil it frequently.

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If the sale is still on I am going to get the $19.95 4 speed HF dremel tomorrow. I have the day off. I will let you know, but I am sure it will do 25Krpm.

But my very old ones (like Chemelec says) work fine. My new dremel does not. I think it is a disposable age now and thing are built cheap and they want you to throw them out and get another as they are cheap.

 

In order to save others from getting one that you are not satisfied with, please post model # and problem. Maybe this will also put a little bit of pressure on the manufacturer(s) to quit selling junk tools.

 

again, the bearings in the dremel designed to take more of radial load then axial (or trust) load making it good (??) grinder/router/cut off/anything but drill. but if it suits your need , it is fine with me.
it is very possible though that the ones that were made 30 years ago had different construction, designed during those nice times when the quality was the paramount and not the low cost of construction.

 

The dremel I have is about 20 years old and has seen light duty. I measured the run-out on it a while back. I think it was around 20 mils which is pretty sloppy. That's about the width of a pencil line which may not seem that much but it's pretty significant. It may not break a carbide drill but it's tough on them. I couldn't feel it move when I flexed it with my fingers but my micrometer showed it.

By the way, my delta drill press is a bit worse than that. I probably need to replace the bearings.

 

They one I never use due to flakey switch at low RPM and noise is a Model 395 type 5. I did it from day one, I thought it would break-in.. Did not use it a lot as I had my old one I tended to save that one. Years later. It is just a flakey unit. Might just be that one though, since I only have one type 5.

 

Yeah, but if you're running your carbide bits at high speed like you should be, the bits go through PCB almost like a hot knife through butter, at least for all the small bits (that make up 95%+ of the holes drilled in most PCB's) so there shouldn't be significant thrust load on the dremel bearings anyway.

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