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Re: Problem with a sextant
From: Joel Jacobs
Date: 2006 Apr 26, 11:39 +0000
From: Joel Jacobs
Date: 2006 Apr 26, 11:39 +0000
Alex,
If you want to trace out the problem, you can buy a dial indicator for not much money. Maybe $25.00 at Lowe's or Home Depot. It would have other uses.
In other messages you mention the writings of others who experienced an unexpalined change in their instruments over time. I just wonder if some of that might not be due to changes in climate as they move from one location to the other. The early instruments were made primarily of ebony and ivory and I would think their expansion and contraction could be a function of temeperature and humidity.
Regards,
Joel
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-------------- Original message from Alexandre E Eremenko <eremenko@MATH.PURDUE.EDU>: --------------
> Dear Joel,
>
> > My suggestion is to take the sextnat frame to a
> > machine shop and ask them to use a "dial indicator" measuring the change
> > in 1/1000 along the arc from its pivot point.
>
> This is not so simple for me:-( You know, I live in a little
> Midwest city where there is no decent watch repair person,
> not speaking of machine workshop!
>
> Of course Purdue University has everything, but my experience
> with showing my inverting scope to Purdue people was negative:-)
> (Finally I found and fixed the problem myself).
>
> Alex.
