In article ,
"John Wilson" wrote:

Does anyone know how to lap the end surface of a rod so that it is perfectly
flat and normal to the rod axis?

I thought I had an article by Geometer on how to do this but I cannot locate
it. It is no longer available on Yahoo Hints & Tips. If anyone has this
article 119/2961 please let me know.

Thanks, John.

We used to lap the ends of laser rods with a collet chuck that grabbed
the rod, which had a large flat face to keep it aligned on the lapping
film. I guess the chuck face got lapped a bit along with the rod-end. I
can envision a design to avoid that, but it makes the whole business
much larger. - basically expand the face so that face can ride on a
non-abrasive surface which is parallel to the surface with lapping film
on it.

It would be pretty straightforward to make such a chuck on a lathe. I'm
pretty sure they can be bought, too, since we did not make the one we
used. It was 15 years or so ago, so I could not tell you who made it,
offhand.

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