XO mill modification

Yes -- don't cut a groove...think instead about adding a strip to the column..and a keyway in the head..I did this acceptably well on a full size mill....a big one from Axminster.

--

Chris Edwards (in deepest Dorset) "....there *must* be an easier way!"

What is the advantage of arranging it that way? It's going to be almost impossible to cut the groove neatly in the head, and also there isn't much metal there.

Cliff.

I'm not familiar enough with the detail of the Sieg to offer specific suggestions.......... I was simply trying to offer an alternative line of thought that might have been overlooked. In the case of my own machine, it allowed me to make a useful modification which could easily be reversed without significant detriment to the machine as a whole.

Needless to say..'horses for courses'.......... --

Chris Edwards (in deepest Dorset) "....there *must* be an easier way!"

Another possibility could be to fit a second column parallel to the first alongside it and mount a bracket with a bronze bush on the side of the head. This would have the advantage that it is easily removed if at some point you do want to rotate the head.

Russell.

This sounds considerably simpler than machining a keyway along an entire column.

Reduces problem to one of finding a decent piece of round bar for the secondary column, and designing in a bit of adjustment for the initial setup.

- Nigel

I'm not so sure that is simpler. The secondary column would have to be absolutely parallel to the first or the head will not slide up and down without binding; whereas I assume it would be a simple matter for an engineering workshop to cut a 14" long groove for me.

Cliff.

Ummm, why?

Cliff,

I have a far eastern mill/drill with a round column and have modified it to maintain the register when raising and lowering the head. I got the idea from an article entitled "Repeatable Headstock Location for a Vertical Miller" by David Machin that appeared in the Model Engineers Workshop No 67 (August September 2000).

This article was about modifying a Dore Wesbury Mill, but the same principle was modified to suit my machine. Instead of a keyway in the usual sense, i.e. square or rectangular, a triangular one is used, and because of the way it is used it is sometimes referred to as a gib strip.

If you wish I can send you a scan of the MEW article, together with the machine drawings of my own version and photos etc.

It is difficult to explain in words how the triangular section key or gib works, but when you see the drawings you will realize how much more accurate it is than a conventional square key. A square key can not be a tight fit or the head will not slide up and down. If there is just say .001" clearance to allow free movement, that .001" at the radius of the column becomes quite a large margin of error at the mill spindle.

Cliff, have a look at this page on Tony's site to see how the Metalmaster did it:

Because the head clamp is feeble allowing it to rotate under load.

Cliff.

Thanks Dick. Would that be the same idea Peter Neill refers to? Anyway, I would be glad to see your information etc. My email address is valid.

Cliff.