Dumont Overcoil Teezer Repair…

[tmac1956]

All:

Because these were missing the adjustable shaft, I got them for less than $100.00. I will post additional pictures after I machine a replacement. These things are soooooo expensive, I just couldn’t pass these up.

Later,
Tom

[tmac1956]

Ok…. Never try to turn something this small and this long without a set of turns or the equivalent for your lathe with driving dogs small enough to handle this. It can be done but – MAN – is it a pain.

So, first I found a piece of steel wire with the correct diameter for the tool which is 0.054″. Next I used a pin gage (+) and determined that the small diameter needed to be 0.025″.

By marking the pin gage with a Sharpy, I was able to determine the required small diameter length which was 0.350″. Next, I put the wire in the appropriate collet, set up the cutter in my tool holder, set the X & Y axis indicators, and started turning metal. After a very few minutes I found out the hard way at what diameter the shaft would shear off. Now what?

So I cut another piece of wire, set everything up again, and turned the smaller diameter to just above the diameter at which it sheared off before, then stopped.

So far so good, but…?
Well, I figured that the only way to bring the smaller shaft down to size was to use the same idea behind the Jacot lathe. I do have a double roller file rest so I figured I could place that in my tool rest, place a small oiled India stone under the shaft, and then take the diameter down in tiny increments thereby reducing the possibility of bending or shearing off of the small shaft.

Once I got the shaft near the 0.025″ diameter, I switched to a 3K grit ruby stone, then to a 8K grit garnet stone. Next I flipped the shaft over and took down the large diameter to the correct thickness.

continued…

[tmac1956]

continued…

I hade to reduce the small shaft length a bit to fit, but I made it a little longer than needed in the beginning. Eventually by trial and error and several hours of “bunnspecialling” I finished the thing. Here it is installed and ready to go.

And one more…

A pair of female turns for my lathe are next on my list… Well, right after I rebuild my Levin Drill press and complete fifteen other things.

Later,
Tom

[david pierce]

Tom,
The part looks great and in the end that is what counts. If I am not mistaken your lathe has a collet tailstock. You can make a cup center by taking a small diameter piece of brass or ,better yet, bearing bronze and center drilling a small hole in the center of the bronze piece. To do this put the small piece of bronze in a collet in the tailstock and the center drill in the headstock. Then, drill a small center hole in the bronze piece. You now have your cup center. The end support proveded by the cup center should allow you to turn the part with a turning tool without it deflecting away from the cutter.
david

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