On Thu, 28 Mar 2013 14:19:00 -0700, "PrecisionmachinisT"
wrote:


"Ed Huntress" wrote in message news
On Thu, 28 Mar 2013 11:37:32 -0700, "PrecisionmachinisT"
wrote:


"Lloyd E. Sponenburgh" lloydspinsidemindspring.com wrote in message . 3.70...
Ned Simmons fired this volley in
:

He's probably running the grinder on the tailstock ways

I might have to take that back... PT later on down mentioned that the L&S
carriage runs on both front and back ways.


That's not to imply that tailstock does not run in a separate set of ways--I simply can not remember.

It's been almost 20 years now since I've worked at a place that had several dozen lathes of various make and sizes all within in the same facility.

If this L&S lathe bed is representative:

http://www.lathes.co.uk/lodgeshipley/

...then it's the same as my SB, only reversed back-to-front. The
tailstock rides on an inner flat and an inner V, while the carriage
rides on the pair of outer Vs.


Actually, the carriage on the lathe in your photo seems to be using both of the outside ways for alignment, in addition to it's also being being supported by the flat way section that's located out front.

I don't think so. It looks to me like the classic Lodge & Shipley
design (Fig. 37 in your book), which is the same as my SB only
reversed front-to-back. The four-way support described as the "ideal
form" in the book has, to my knowledge, long since been abandoned.
That would be a scraping/aligning nightmare. Likewise, I don't think
the L&S supported the carriage on two Vs and an assymetrical flat,
because wear would be uneven between the flat and the Vs and, again, a
nightmare to keep aligned. You'd be obviating one of the two big
advantages of V ways. With two flats you'd at least have more balanced
wear but that isn't what a L&S has.

My SB just has clearance where that screw-on plate shows in the photo
I linked to. I suspect that it's probably just a cow-catcher. g It
may be holding a felt wiper.


According Oscar Perrigo; "lathe design, construction, and operation ", this appears to have been yet another iteration in a long series of carriage bearing "improvements" that evolved over the years...


Eventually, the inside vees were dispensed with altogether, settling on a design that used a pair of vees and a pair of flats in a configuration that came to be called the "Ideal Form"

I don't think it's around anymore.


FWIW, the problem with using 4 vees was because the underside of the carriage needed to be cut away in order for it to clear the inside pair, which weakened the carriage.

--prior to the advent of the "ideal form", the outside pair of vees was invariably used to carry the carriage; this allowed the carriage to be shaped like a capital letter "H" thus providing substantial addional stability while also allowing it to get in real close to (or even underneath) the chuck and tailstock ram.



Thus, if he's riding on the tailstock ways, he could get some
improvement. If not, not.


It'd still undeniably be a hack-job, Ed.

Yes it would.

--
Ed Huntress