On Sep 4, 6:43*am, wrote:
On Sep 3, 12:04*pm, David Harmon wrote:

On Wed, 3 Sep 2008 03:01:46 -0700 (PDT) in rec.crafts.metalworking,
wrote,

Similarities betwixt and between Smithy's Super Shop and Emco-Myer's
Unimat 3:

Two column bed ways

You mean the cylindrical shaft bed of the older Unimat and Unimat
SL? *No, the Unimat 3 has a cast iron bed with an inverted V in
front and a flat in back.

That's right, it was the Unimat and the Unimat SL, as as well as the
NC version, that had twin column bed ways. I remember now...

Doug

The dual column design, convertible from table saw to drill press,
seems to be the basis for almost all my thoughts on universal machine
tool design lately. I wonder if a lead screw could be run through the
column closeest to the operator in lathe mode. If that were done,
thread cutting would be available and that is one thing the Super Shop
does NOT have.

In such a dual-column machine, of Super Shop scale, might the tubular
bed ways be slotted full length allowing access to a nicely shielded
lead screw, without them springing open with an increase in diameter?
It's a question of residual stress in the steel. Perhaps MSC Direct
can check with the maker of the 2 inch hollow linear motion ways they
sell for me. I have two such bed ways spare from Smithy; when I
complained they were finished to about 16 microinches and were
abrading a fine aluminum dust from the castings of headstock and
carriage, they sent two to me. One each with rack teeth milled in
place, and one without. I'd explained to them I have accessorized my
Super Shop to hold the tubes for hand polishing, hanging from the
headstock in the vertical position. Such bed ways from MSC are $500
each. Smithy provided these two GRATIS! Way to go, Smithy! I'll have
to ask Smithy about residual stresses, too.

Doug