"CAMCOMPCO" wrote in message
oups.com...
Hi all,

Is there a way I can get a mirror like finish on a turned piece of
metal? I know I can use 1000 grit and finer on a piece as it is
chucked and turning in a lather, but how about the bored hole? How
would I get a, say, 1/4" or 3/8" internal surface glass smooth? I am
thinking of some sort of expanding reamer that I could put a 1000 grit
wet/dry sheet around and insert it in the hole as it is turning...seems
like I would just bunch up the paper though ;-)

Anyone ever have to get something "barring" smooth internally....what
did ya use?

Thanks again gang....as always, any help is greatly appreciated

John

I haven't visited the newsgroup in quite a while, and you have probably
already finished your project but here is how I would do it.

I would use the same basic procedures that are used in making a custom rifle
barrel. First drill the hole undersize, ream and polish for a good finish
leaving the hole slightly undersize. Then silver solder a button (ball
bearing) to the end of a rod that is smaller than the hole size. Using a
good high pressure lubricant such a moly powder, or even anti-seize compound
that contains a fair amount of copper I would push/pull the button through
the barrel. Doing this with the hole about 0.005" undersize to start with
should leave a good finish.

Clean the inside to remove the moly or copper with a good penetrating oil
(such as Kroil) and very mild soft abrasive such as "J-B Bore Compound".
This is what is used by some shooters to clean the moly and brass from their
rifle barrels, without causing any extra wear. The J-B is a soft vegetable
based abrasive and will not remove any steel.