In article ,
Gunner Asch wrote:

On Tue, 19 Jun 2012 10:20:05 -0400, Joseph Gwinn
wrote:

My US Burke Millrite model MVI vertical mill (resembles a Bridgeport,
but 2/3 the size) came with a X-Axis power feed, an Asong AS-250. This
unit never really worked correctly, and kept on blowing speed control
pots out, as discussed in the thread "Repair of an Asong AS-250 X-axis
power feed" in January 2010. This is a general problem with Asong.

[snip]

What is not mounted is the switch that stops motion if the table moves
too far in either direction. The switch is designed to fit on a
Bridgeport, and is far too large for the MVI, and wrongly-shaped to
boot. The Asong switch had the same problem, and was never mounted
either. The theory is that the 0.125" brass pin will shear and save the
day. I will eventually make a custom switch for the MVI.

Joe Gwinn

Most of those switches are simply mounted in the middle of the slide and
a stop on the table is used to control end of travel.

Its easy to mount that switch and then simply figure distances and
either install a stop bolt to hit the switch buttons or if you have a
dovetail on the front of your table..a pair of movable stops.

All true. The problem is the limited space, especially with the DRO
scale. And limited time.

There is a 1/4" T-slot in the front of the table, and the moveable stops
use this T-slot. The is a fixed stop in the center. I would replace
this fixed stop with the switch housing. Within the housing would be a
pair of microswitches. I just have not gotten around to designing and
fabricating it.

Joe Gwinn