Gram Gauge

[Bill Ballard]

At 4:38 PM -0400 10/14/00, Jon Page wrote:
>McMaster Carr has force gauges.
>http://www.mcmaster.com/
>
>Check out the digitat readouts: #'s 8727T17  & 8727T54   $608.00 & $842.00
>
>Their Pivot-Arm gauges are $135 (lower on same page).

The above is what you'll need, ones with auto-zero and peak memory 
storage. Springs and weights don't have this. Remember that springs 
work by measuring their distortion. This is easy to read while the 
key has yet to break into motion because the object on which the 
distortion is based is stationary. As soon as the key moves, your 
hand holding the spring gauge has move at the exact same speed as the 
key, so as  to be certain of reading the force required for the 
minimum readable motion of the key. I bought the P.K.Neuse set of 
three (10-0-10, 50-0-50, and 0-150g) twenty years ago when they were 
being offered by Jensen Tools. For the reasons detailed above I 
decided that, for DW and UW, dead weights were better than 
spring-based force gauges. But when my MacArthur grant come through 
I'm definitely getting the digital model. (RS232 into a PC would be 
nice!) About 8 years ago David Stanwood was investigating strain 
gauges to do this measuring. It is finicky work, when done seriously.

Industrial engineers have all the best toys!

Bill Ballard RPT
NH Chapter

"If ducks were smart enough and well-built enough, they'd be shooting 
at us. It's not my fault they can't aim and shoot."
     ...........Talk Show host Rush Lamebaugh, explaining why duck 
hunting is a sport, 1/12/98