From: Robert Bastow <"teenut"@ hotmail.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Lathe replicating itself?
Date: Thu, 03 Feb 2000 12:03:37 GMT

I think there is some misaprehension about what is meant by "replicating"

It would be VERY difficult ..if not impossible for a Bridgeport mill to make a
perfect, full size, Bridgeport Mill..Just as it would be next to impossible to
make a Harding HLVH one a Harding HLVH.

Indeed it would be very dificult to make EITHER of those machines, even if you
had first class example of BOTH to work with.

However..for a lathe to make a working lathe...of SOME sort..has been done many
many times.  Headstock castings can be machined flat on the boring table or
faceplate. Beds can be round..many still are.  Once headstock and bed are
assembled the lathe can accurately bore its own spindle bore..etc.

Similarly, some form of functional milling device could be made on a milling
machine..but in my honest opinion, a great deal more difficulty.

After all, a mill is just a highly specialised and modified lathe!!

Given my druthers, I would MUCH prefer to make a lathe with a lathe..rather than
a mill with a mill.

teenut



Janos Ero wrote:
>
> David & Pam wrote:
> >
> > Forgive the trivia, but one of the toolmakers here and I had a discussion as
> > to what machine tools would be capable of replicating itself. What I mean by
> > that is, what machine tool is capable of making every piece of itself. I say
> > it is a lathe fully equipped with some minor milling tooling thrown in for
> > good measure.
> > Has anyone tried this out there?
>
> What about the bed and headstock?
>
> Janos Ero

From: Robert Bastow <"teenut"@ hotmail.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Lathe replicating itself?
Date: Fri, 04 Feb 2000 04:24:13 GMT

The first accurate lead screws were generated on a soft lead cylinder, using an
inclined knife cutter on a freely sliding carriage.

Varying the angle of the knife edge, precisely varies the pitch it cuts.

Refinement and translation into harder metals followed, by a variety of means.

teenut

Sfc149 wrote:
>
> What about the leadscrew?
> Where did Genesis Lathe get its leadscrew
> which would be needed to replicate itself?
> Sig.

From: Robert Bastow <"teenut"@ hotmail.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Lathe replicating itself?
Date: Fri, 04 Feb 2000 04:34:06 GMT

You can also generat a reasonably accurate master screw by wrapping two lengths
of, say, 1/16" hardened  wire closely around a softer cylinder.

Carefully tap one of the wires so as to create a slight "bed" for it. Solder the
ends of that wire and remove the other, solder the remaining wire into its
"bed"  You know have a fairly accurate 1/16" pitch screw.

Use this to cut a more durable screw in steel.  Measure pitch error and make a
flat cam that will compensate for pitch error by advancing or retarding the nut.

Repeat through as many iterations as it takes, to get your master screw within
millions of an inch of true pitch!  Use of an extra long nut helps to average
out errors.

Tedious?  Maybe, but our ancestors seemed to be a lot more determined and
patient than we are!

teenut

From: Robert Bastow <"teenut"@ hotmail.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Lathe replicating itself?
Date: Fri, 04 Feb 2000 12:18:44 GMT

Not Mine!!

I am a duplicator, not an originator!

But using a similar technique one can generate two, three or more, start
threads..using the appropriate number of wires. I can remember a childs
old-fashioned, "pump action" spinning top (Humming Top) where the archimedian
spiral that powered it, was made by simply wrapping a wire around a spindle and
soldering it in place.

Gunsmiths of old used a similar technique to generate wooden or metal masters
for their rifling machines.

I made the first rifling guide I ever used by twisting an annealed length of
5/16" square BDMS with one end in a vice and the other held in a big tap
wrench.  Crude...but the barrel WAS accurate enough for my (Black Powder)
purposes at the time.

teenut


Janos Ero wrote:
>
> Robert Bastow wrote:
>
> > You can also generat a reasonably accurate master screw by wrapping
> > two lengths of, say, 1/16" hardened wire closely around a softer
> > cylinder.
> <snip>
>
> Brilliant idea, indeed.
>
> Janos Ero