On Sat, 14 Feb 2004 22:04:12 GMT, Gunner
wrote:

A probably really stupid question about dial test indicators.

I stumbled across a minty Lufkin LARGE dial, dial test indicator
(.0001) for $5 the other day. Crystal is good, everything moves
smoothly..but the "pointer" was missing. A customer gave me one that
screws in just fine..but here is the question...and Im blushing to
ask..

How long are the pointers supposed to be? Perhaps Ive had a stroke
or its a case of brain fade..but doesnt the length of the pointer make
a difference as to the actual measurement displayed on the dial?

Length of lever and all that stuff.

Gunner

"To be civilized is to restrain the ability to commit mayhem.
To be incapable of committing mayhem is not the mark of the civilized,
merely the domesticated." - Trefor Thomas


Gunner the contact point length is important.. the higher the
resolution of the indicator the more important the contact point
length and the angle at which the contact point touching the surface
to be measured is..

Other then Lufkin docs.. take your contact point.. make sure the
contact point is does not have flats.. should be a perfect
sphere...just test the movement on a height check.. a good test is
plus of minus .0005.. in .0001increments.. with the contract point
horizontal to the height check surface....and see how close it is..
should be perfect at .0005 and start to differ around .008 or so..
repeatability is always much better on test indicators then accuracy
in travel , depending on the range quality, etc..

Lufkins are a little stiff so don't be discouraged if you can't see a
..0001 movement very well... and it could be dirty, etec..

later,
Mike