what is this ? direct indicating vibration pick up

[razors edge]

How was it used -ww2? Any info will be appreciated. Thanks

[emmagee1917]

It was used to check the balance of the propellers on aircraft.
Chris

[dave]

I was a vibration analyst for 10 years at an oil refinery and that looks like a very primative device. How was it used w/o picking up vibrations from the engine? It certainly was not attached directly to the prop. Looks like photo election cell or somthing?

[emmagee1917]

A 5 minute search on Google told me what is was and what it was used for. No Instructions were included . I'd guess start the motor and get it spinning , then kill the motor . We use something like this on car motors when we have an unlocated rattle. Placing the blade of a large screwdriver on the alt. , ps pump , water pump , etc. and hold the handle to your ear allows you to isolate those vibs from the rest of the engine. A bad bearing or loose / bent shaft or vane will pop right up.
Chris

[jgaynor]

Im guessing the GI flashlight is just the battery holder/power supply. It looks like there is some sort of sliding scale on the black piece. Maybe the scale provides a readout of the vibration frequency??

[Varmintpopper]

possibly a series of tuning forks with different freguency ranges and a visual means of determining freguency. Just a guess though.

Good shooting

Lindy