Re: [ATM] Not tde or tue, important oblate spheroid, ellipsoid

["Bob May" <rmay@nethere.com>]

Ah, sorry about that!  Like they say, the Internet is a big
place!
Probably the best thing to say here is that the chinese make very
cheap tools, even tho they may not be up to the standards
elsewhere, they do tend to do their job.  Any old source for dial
indicators will do well and you don't even need to have the
indicator to be anything more accurate than the coarsest ones
available.  I don't know how coqrse they get with metric but in
inch sizes, a thousandth of an inch are the common ones and are
more than accurate enough for the job.
I'll also note that there may be (if you're in a bigger city) a
used machinery place and one of the things they do sell is old
measuring tools for much less than what a new one would be.  You
might, like I've had to do with some of the dial indicators that
I've bought from such places, hqvve to lubricate the tool.
Sometimes they are also stuck because of old oils that have
gotten into the measuring rod and its bore and bummed up the
works.  Those are best handled with a bit of kerosene until the
run freely;.  Get the longest travel ones which is usually 25mm
or so.  Leave the 50mm ones alone as the guy will probably wqnt
more for them  and the long travel isn't needed.
Bob May
Due to the large volume of SPAM thaat I'm getting, add an open
square bracket to the subject line or my spam filter will reject
your post~
rmay at nethere.com
http: slash /nav.to slash bobmay
http: slash /bobmay dot astronomy.net
Replace the obvious words with the proper character.

_______________________________________________
ATM mailing list http://www.atmlist.net/