Interesting gadget

[Neverenoughwatches]

As we all love tools ( except the price of them ) i came across this curious device on ebay. I'm not buying but i thought some of us might be interested to see it. Its description from the seller  is a mainspring dynamometer  ???

Edited April 21, 2023 by Neverenoughwatches

[nickelsilver]

I had one of these years ago, yes it's to measure the force of the spring as it's wound and unwound; it attaches directly to the barrel arbor. I got it just as curiosity, and it only had one collet so I eventually sold it. Neat little machine. There are much larger industrial versions that are about a meter long, and use a calibrated spring blade that carries a pen and makes a trace on a long piece of paper; those have been replaced with digital equipment now.

[kd8tzc]

Any idea what the two different scales are measuring?  I take it the one of the right is grams of force, but uncertain of the one on the left.  Torque possibly?  It's interesting as the scale on the left gauge is reversed between the top reading and bottom.

That is a very cool looking piece of equipment.

[nickelsilver]

2 minutes ago, kd8tzc said:

Any idea what the two different scales are measuring?  I take it the one of the right is grams of force, but uncertain of the one on the left.  Torque possibly?  It's interesting as the scale on the left gauge is reversed between the top reading and bottom.

That is a very cool looking piece of equipment.

Yes, the right hand one is force, the left scale is the turns of wind.

[kd8tzc]

Okay, thanks.  That makes more sense being turns as it doesn't have a scale on it.

I am seeing what looks like a red arrow below each of them... is that just part of the design, or was that a "Max" indicator or something?