re:Re: Handwheels, retrofits, manual machining

Fred,

I've stood in front of manual BP's and "spun my wheels". I've stood
in front of VMC's and "punched it out". I've NOT used a BP CNC
retrofit!

As I read your post I just KNEW I had to post a reply saying how
this "feel" thing you're talking 'bout surely is cancelled by
the "drag" of the motor drives(inertia, belts, etc).

Read a little further and I thought, Great. Here's Fred saying it's
OK to manual machine with B/S, when Jon A sez, "don't do it!". I'm
thinkin' Jon A has got it right, and I need to remind the list...

Then I get to thinkin' that MAYBE the REASON you can get away with it
IS the motor drives being powered down!!?

(more replies inserted below)

>However when you are finishing the sides of a slot the you can
>control the final size by the feel of the cut, it is not necessary
>nor appropriate to use the CNC control for this<snip>It also takes a
>lot of practice & hands-on usage to tell the difference between .002
>and .003 depth of cut.

Fred, You've got to be kidding! NOT appropriate!?? I DO have these
hand skills, and I am QUITE pleased to use the consistency and
repeatability of the control to give me GREAT results time after
time. And others with lesser "hand skills" can also create great
parts.

>The important place to have this kind of control is where the sound
>and vibration of the machine make the action of the cut impossible
>to sense by sight, smell or sound. Since the hand feel is actually
>more accurate and reliable than the others, it can be used in this
>kind of cutting condition.

Again, You've got to be kidding. THIS is EXACTLY the place where CNC
shines! Hand "feel" is GREATLY reduced by vibration and masking
sounds. I'll let my control handle this situation, thank you.

>On the benchtop machines, it may be that the control handles and
>screws are so coarse that you cannot feel the difference one way or
>the other.

A coarse screw will "transmit" more of the "feel" to the operator
than a fine screw. A fine screw will allow better "control".

>On a Bridgeport machine there is no question that you will want to
>leave the control handles on the machine if at all possible. It is
>also fairly easy to use them without the handles and many retrofits
>of this type of machine have included a round aluminum disk instead
>of a handwheel to reduce the effects of the inertia in the heavy
>cast handles, but still leave the option to do fine-precise work.

This makes sense. I've seen these disks "out there".

>Lastly about safety. NEVER NEVER NEVER climb mill on a manual
>machine period. The acme screws used in Mills will not make this
>kind of cut without causing harm to people, tooling, parts and the
>equipment itself.

Good general advice. Full size mills.

<snip>My personal experience with climbmilling on my own and other

>people's machines is that there are a couple of places where if done
>very carefully, it is OK to use climb milling in manual machining.

It's probably important to point out that what you can get away with
on a sherline does not directly translate to the full size mills!!

>Axis locks may be the difference in my experience and those of
>others that have problems with manually machining on a machine with
>Ballscrews. Personally I much prefer the ball screws over the
>acme, as there is no backlash to account for & there is reduced
>effort required to move the table and workpiece loads.

Or the point at the top of this post ???

>Gotta throw this out too - there are lots of rumors about new
>Windows based controllers coming soon.

You said controller-ssss, as in more than one.. What means "soon"?
Who??

Ballendo