Subject: Re: lathe differences

From: [email-masked] (gary preckshot)
Date: 19 Nov 1993 17:20:52 GMT

In article <[email-masked]>, [email-masked]
(Tim Kirby) wrote:

> : Perhaps "Engine Lathe" harks back to the days when machine shops were run by
> : overhead shafts and belts, and a lathe with the motor on-board was an
> : exception
> 
> John, what have you started? ... everyone's digging through their bookshelves
> now.
> 

Yeah, ain't it wonderful?

Here's more.  My 1935 vintage Southbend "How to run a Lathe" contains two
pages on toolroom lathes with great emphasis on the idea that Southbend
toolroom lathes were very high precision.  Several line cuts of belt-driven
Southbend toolroom lathes.  No engine lathes are mentioned, but Southbend
does refer to "motor-driven" lathes, and has line cuts of several lathes
with the jackshaft driven by an electric motor, but still with crowned cone
pulleys and flat leather belt drives for the final transmission to the
spindle.  Kind of conservative.  Also rather kludgey.

My 1960's vintage "Tool Engineer's Handbook" contains a description
separating engine lathes from toolroom lathes.  Engine lathes are general
purpose machines, as distinguished from turret lathes and automatic screw
machines.  Toolroom lathes are engine lathes built to higher standards of
precision for the purpose of (you guessed it) making tooling.  Seems in the
earlier part of the century the toolroom was used for more than storing
cutters.  They actually made cutters (and dies) instead of buying them. 
Consequently, if you wanted reasonable precision in your production
machinery, you needed higher precision in the machines you used to make
tooling to fit.  A very pertinent subject for something calling itself
"Tool Engineer's Handbook".

G.-