11.29.2012

milling about

Finally finally, finally got the Taig mill up and running again.
The only defective part has been me (ta da!).

One of my laments, before it was all disassembled and packed away for the (long ago) move to my new domicile, was the lack of workholding devices that were provided with the machine. The secondary market was also a bit thin at the time. But it's a machine tool; you're supposed to make things with it.

Taig's T-slots on the milling bed are not the same size as most other mini-mills; even a 1/4-20 threaded rod is really too big to use. Taig favours 10-32 hardware and (for the mill) includes only a couple of elongated, flat steel nuts. Injudicious use of the cap screws when tightening up will cause scoring of the T-slot bottom. A more elegant solution is demanded.

Certainly, there are 3rd parties that now sell accessory clamping kits for the Taig. However, it's time to make something (see end of 1st paragraph) for it myself.

Once the vertical column was trammed, I dug out the ER16 collets and the largest milling cutter I could find in the boxes (3/8"). It turns out I have several larger ones but they wouldn't do the job any faster in this case. The Sowa toolmaker's screwless vise was installed and squared up.

A 1/2" square bar of aluminium (6061?) was inked and scribed to the dimensions required, then clamped in the vise on top of two parallels. Flakes flew off the sides as I carved a 1/8" x 1/4" step into each long face of the stock. This produces a nice sliding fit in the T-slot while still not jamming on every strand of swarf.

Tomorrow's task is to mark out the holes, drill, tap and de-function-ise the bottom threads to prevent the screws from passing completely through. Then I'll mark off and slice the individual T-nuts from the bar. Later batches will be sized for both the lathe saddle T-slots and the front lip of the mill.

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