Re: [CAD_CAM_EDM_DRO] Re: Bridgeport Mill by Adcock and Shipley

"Fitch R. Williams" wrote:

> On Thu, 05 Jul 2001 19:12:25 -0400, "David M. Munro"
> <munro@...> wrote:
>
> >One rarely sees CNC horizontal mills of any
> >description.
>
> Not arguing with either John Stevenson's wise counsel, or yours, but I
> would think that a horizontal CNC mill, factory built that way, and
> properly set up, would have some serious advantages for heavy duty
> pocket milling due to vastly superior chip clearance.

A plain horizontal mill, CNC or manual, has limited applications in
most production work. If you need long parts cut to a particular
cross section, there are many ways to do it cheaper than hogging
it out of solid billets. Extrusions are easily available, and used much
more than 50 years ago. If you DO need this kind of part, and this is the
only way to make it, there is nothing like a beefy horizontal machine
to make quick work of it. These machines are also used in HBM (Horizontal
Boring Mill) type jobs, especially "reach-through" critical alignment
work. If you are making gearboxes, for instance, you need all the
bearing mounts to be totally in line and parallel to each other.
Some companies use a big HBM to bore the front face holes, then
switch tooling, and reach through the first holes to bore the corresponding
holes in the back face of the gear case, without dismounting the
workpiece. This guarantees the holes are REALLY aligned.
(I saw one setup where a GIANT HBM was used to bore "wheel"
bearing mounts for an armored personnel carrier this way.)

Jon