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276145 Matthew Groves <grovesthegrey@g...> 2022‑08‑13 Pricing plumb bobs. Impossible task?
So the friend’s collection that I’m selling has a tub o plumb bobs. 

How the heck do you price em?

https://share.icloud.com/photos/014weepI_KjNQEVNTzxTmoLIw

Matthew Groves
Springfield, MO
276150 the_tinker <tinker@z...> 2022‑08‑15 Re: Pricing plumb bobs. Impossible task?
Mathew,

Can't help much with pricing, I see those old bobs high and low. One bit
of advise though - more than likely some of them are full of Mercury.
Some folks will recoil in horror but the knowledgeable ones will pay
your price for an old mercury filled plumb bob.

On a side note, my Dad used to tell me that part of he and his friends
routine for getting duded up for a Friday night on the town was to rub
mercury on all the silver coins in your pocket to shine them up. He
lived to 89 and was active to the end.

-JP
276151 Matthew Groves <grovesthegrey@g...> 2022‑08‑15 Re: Pricing plumb bobs. Impossible task?
JP, I know how to spin an egg to discover if it’s hard boiled or raw, but is
there a trick to knowing which bobs are filled?

Matthew Groves
Springfield, MO
276154 Kirk Eppler 2022‑08‑15 Re: Pricing plumb bobs. Impossible task?
The density will be higher.  Figure out the volume and weight of a normal
one (like a General), then gather the relative heft of others, calculate
the density of it, should be much higher.

There are rumors that the mercury is supposed to move to dampen the swing,
but Starrett etc never made that claim, just higher density.

Mercury is 13.59 grams per cubic centimetre

Steel is about 7.9

So if the whole thing was mercury, would weigh almost twice as much, but
would be hard to get a string around.

So guess at 30 - 50% higher weight for the same sized plumb.

This says even less, 25% for the same size

https://archive.org/details/StarrettToolsCatalogNo25/page/n64/mode/1up

Kirk in Half Moon Bay, still looking for hewing hatchets in the mess

On Sun, Aug 14, 2022 at 7:33 PM Matthew Groves 
wrote:

> JP, I know how to spin an egg to discover if it’s hard boiled or raw, but
> is there a trick to knowing which bobs are filled?
>
>


-- 
Kirk Eppler in Half Moon Bay, CA 

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