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Old August 11th 07, 10:25 AM posted to rec.radio.amateur.antenna
Ian White GM3SEK Ian White GM3SEK is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 232
Default Hammer drills and ground rods, followup

Owen Duffy wrote:
Ian White GM3SEK wrote in news:vjC1vRDSbWvGFAt1
:

...
The only special part is the slotted shank that snaps into the chuck.
This is exactly the same on every SDS+ drill bit and tool, so you can
simply buy the cheapest item you can find (probably a small masonry

bit)
and chop off the end that you don't need.

Then find a short piece of steel tubing that will slide loosely over

the
end of your ground rods, and have the two parts welded together.


This can't be too hard, can it Ian!

I just looked on Ebay here in Oz, and I can buy a 20mm SDS chisel for
about $14 delivered. I would cut the shank just above the chisel end and
slip a 50mm long piece of 20mm NB steel pipe over the remaining shank
end, weld it on, and there you go.


Good idea! The shank part of an SDS+ tool is quite a small diameter, so
it's a good idea to buy some kind of tool that widens to about the same
diameter as the ground rod.

Ideally, the end of the tool should be
harder, but if you are only driving a few rods, you probably won't split
the collar.

The collar needs to be a *loose* fit over the rod, so there should be no
risk whatever of it splitting.

Wrap your copper clad earth rod with a good few wraps of electrical tape
so that the tool does not noodle up the end of the electrode.

The ground rod is only mild steel, so the top of it will probably
mushroom over anyway (which is the main reason for making the collar a
loose fit). In general, you'll have to plan on making the connection a
few inches below the very top.

Protect your eyes when using this type of tool, especially improvising
tools from cheap asian chisels.


Even the cheapest SDS accessories have to be made from good tool steel,
or else they couldn't handle any normal use. Also, the collar acts as a
safety guard around the place where the hammer action is being applied.

However, protection is always a good idea. When you're driving a typical
4ft rod, the action begins right up at chest level, and then moves
slowly downward past other vulnerable parts of the anatomy.


--

73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek