Re: [GrizHFMinimill] Milling machine question
- Harry: Your answer is timely for me. I have a round column mill.
Recently, I've encountered a number of situations where I need to
change from starter drill, to regular drill bit, mill bit,
countersinks, etc. without losing x-y registration. The z-travel of
my spindle isn't enough to accommodate many of these changes and I
have to raise the head to give more room. I haven't learned how to
maintain the registration when I raise the head.
Machines with the maximum spindle-to-table distance seem to be
knee-type mills. I've been wondering how easy it is to drill with one
of these. Can you speak to this?
>Very few large (full size) vertical milling machines have a drilling
>capacity per se. You can of course, still drill with them, but
>instead of pulling a handle down as in the mini mills you have to
>fit the drill into a collet chuck in the tool head or use a chuck
>fitted to the head, You then have to crank up the table to move the
>workpiece into the rotating drill.
>Most of these machines are far to large to use for everyday
>drilling. I suppose the manufacturers think that if you have several
>thousand Dollars to spend on a large Mill, you will probably be able
>to afford a precision drill press out of pocket change, or, a radial
>arm drill if your wanting to drill really large holes.
>In a message dated 03/10/2007 19:53:12 GMT Standard Time,
>I was looking at some catalog and noticed the higher priced milling
>machines don't have drilling capability. I'm sure it must be a good
>reason for it, any idea why?
- Barry, That would work too!
The one 100 Meter range i normally shoot at has relatively small
benches and as any BP shooter knows, benches get crowded real fast.
On top of that a large clear area needs to be available on the bench
for swabbing the bore.
The small bench tripod i previously used was in the way big time. And
a large tripod off to the side off the bench is a PITA because i
gotta get up off my lazy arse every round to use it!
With this contraption, its clamped on the bench to my left taking up
negligable precious bench area. That angled arm is 360 deg. rotatable
and can be rotated even further out to the left which allows the
scope to be totally out of the bench perimeter altogether. By the way
i'm a right hander.
Putting this thing together was a little more involved than the
pictures would indicate at first glance.
Its hard to see from those poor pictures, but i added that angled
1/8" plate for added rigidity. Its actually welded to the 1/2"
threaded rod which can't be seen in the pictures. Also welded to the
clamps are 1/2" coupling nuts which that all-thread screws into
allowing an adjustable elevation span of about 6".
The wing nuts on the clamp are there for added rigidity. They
eliminate any clamp movement due to factory casting slop and loose
I had to totally revamp the C-clamps in order to get those wing nuts
where they are. I removed the floating pads from the clamps, turned
em down perfectly flat including their shoulders on the lathe and
placed the wing nuts on the clamp's threaded rod. Then to refasten
them back onto the clamp, i drilled 'n tapped 6-32 threads and the
end end of the C-clamp's threaded rod, coutersunk the pads for 6-32
cap screws and put it all back togather.
In order to get the clamp's threaded rod in the lathe for drilling
the hole for the cap screw, the stock crank levers were cut off and
pitched. I then machined new end cap keepers for the new crank levers
with 6-32 set screws. All wing nuts were ground flat on their working
surface with a tool i made as were all there mating surfaces.
I wanted zero movement due to the clamps.
Probably more than you wanted to know!
Barry Young <barryjyoung@...> wrote:
> Hi Ken:
> Thanks for sharing the photos. It looks like the scope
> is in the right place for use at the shooting bench.
> A few years back I made a mount for my spotting scope
> by pressing a 1.25 inch round aluminum bar into the
> center of a 25 pound weightlifters cast iron weight
> plate. The weight did a very good job as a base. This
> allowed me to move the scope to any place on the bench
> without removing clamps. A second bar was arranged at
> 90 degrees to the vertical bar via a clamping block
> made on the minimill. Attached to this horizontal bar
> was a high quality tripod head. This worked very well.
> When I changed to a much more powerful astronomical
> telescope which allowed seeing holes in targets out to
> 300 yards, I sold the setup. Sorry I have no photos of