On 12/16/2017 5:12 AM, John B. wrote:
On Fri, 15 Dec 2017 18:38:09 -0800, Jeff Liebermann
wrote:

On Thu, 14 Dec 2017 19:23:37 +0100, Emanuel Berg
wrote:

Once there was a guy who had a bounce free
hammer and I asked how it worked. He explained
the little balls going up and down. I was
terribly impressed by this. But then one day
I used one myself and slammed it open and could
see it all first hand. It was still a good
answer but quite possibly that's the way he had
found out as well. Somehow took the magic out
of it.

Perhaps you are thinking of a "dead blow hammer"?
https://en.wikipedia.org/wiki/Dead_blow_hammer
https://www.google.com/search?q=dead+blow+hammer&tbm=isch
The good ones are full of tiny steel balls. The cheap junk uses sand.

"Learn by Destroying(tm)" also means that you really don't understand
how something works until you've broken it, taken it apart, and fixed
it. I've learned more from things I've broken than from playing with
the pretty knobs, reading the instructions, or using it for its
intended purpose.

Re "Dead Blow Hammers". For work in the shop we used to cast hammer
heads out of commercially pure lead. As we had the mold we used to
recast the hammers when the heads got badly banged up. Surprising how
little actual lead was lost in use.

As for Learning by destroying". After a number of years of replacing
bent, busted and broke eventually the penny will drop.... Read the
F...ing Manual. First!
--
Cheers,

John B.


"as we had the mold".
I cast my lead hammer in a steel can with a piece of water
pipe handle stuck into the side of it.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971