Re: cordless tool 18V to 12V converter

David Billington <djb@invalid.com> writes:

On 15/03/2024 18:35, Richard Smith wrote:

Leon Fisk <lfiskgr@gmail.invalid> writes:
>

On Fri, 15 Mar 2024 13:31:43 +0000
Richard Smith <null@void.com> wrote:
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<snip>

http://www.weldsmith.co.uk/tech/minerals/240314_rocksplit/240314_rocksplit_drill_feathers.html
"Rock-split granite with "cordless" SDS drill and "feathers""

Rich,
>
NICE job! You have a working solution to this problem👍
>
Forgive me... but my mind immediately went to why not make (or buy)
some larger feathers to fit the Pneumatic drill hole and maybe some
smaller feathers so your battery drill could use a smaller drill hole🤔

Not at all "forgive" - comment welcomed.
>
There are some large feathers for the 32mm to 34mm hole.
Thing is, from my observation, they work no better than the small
feathers on this granite.
Line of small holes with matching feathers is "it".
>
Problem is the compressor isn't running all the time.
Would be in a working mine, but this is a "hobby" mine.
Splitting rocks and clearing debris is like an infil job which comes
when it comes.
Takes several people and some time to get the compressor running.
Not going to happen when you find yourself with some time mid-way
through a club morning at the mine.
>
If I could make some wedges of the same taper but thinner, maybe could
come down to a 12mm / half-inch hole
Area-ratio, so proportional to diameter-squared
(/f (expt 14 2) (expt 12 2)) ;; 1.3611111111111112
(/f (expt 12 2) (expt 14 2)) ;; 0.7346938775510204
73% of the area.
Would be well worth having.
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Yes absolutely {thumbs-up}
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Best wishes, Rich Smith

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Richard,
>
Have you tried or considered the old method of dry wood hammered into
the holes and then wetting it, not something I've tried but an article
here
https://www.researchgate.net/figure/Rock-split-by-using-the-swelling-pressure-of-wood-Egypt-2001_fig5_267834899
.

Not tried it - should, to respect forebearers and live their experience.
Modern there is "splitting compound".  Mix the powder with water - is
expansile when "sets" - can be used to burst rocks.  Never tried that.
But yes if find opportunity would be good to try the ancient method and
experience it.  Would be good feeling of treading prior footsteps should
I get it to work.