"J. Nielsen" wrote:

cross posted to rcm. Thanks for letting us use the dropbox

Inspired by Anthony, here's another "How would you do it?"

A couple of years ago we got an email from a customer who wanted a special
part ground.


http://www.metalworking.com/DropBox/ Search for "pigtail" (four files)

About the part:

So here's the deal:

The part was to be ground on the cylindrical (white) part of the tail
roundness +- 0.0005" as it had to seal against the stripping plate.
The fillet at the base, and the tapered part should also have a "grind
quality" surface finish. Actual size was not too important.

How would you have done it?


Jan:

Send it out? LOL We don't have a 4th axis grinder.

But if I HAD to give it a try, I might *try* to do it in a vertical
mill. Mount the base in some bored soft jaws, mount a surface grinding
wheel in an extended holder, radius dress a full radius on the edge of
the wheel making sure the radius on the bottom of the wheel matches the
fillet radius. And *mill* it going round and round the part like a
sideways ball end mill. Gibbs allows geometric tool definitions that
might cover this. Chatter would probably be a problem until the exact
speed (normally 3600 RPM for grinding wheels), and feed were worked
out. I have no idea if this would actually work, be fun to try though,
and I hope they would furnish a solid model. g

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BottleBob
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