Radiator earth bonding

[EFLImpudence]

There is the famous case of a woman being electrocuted when she touched a metal kitchen utensil rack which was live because one of its screws was touching a buried live conductor while her leg was touching, I think, an oven; so it would have been better had the oven not been earthed.

However, no one would advocate not earthing an oven.

 

[EFLImpudence]

As for drilling walls: use a cordless drill with the electricity switched off.

 

[JohnW2]

There is the famous case of a woman being electrocuted when she touched a metal kitchen utensil rack which was live because one of its screws was touching a buried live conductor while her leg was touching, I think, an oven; so it would have been better had the oven not been earthed. .... However, no one would advocate not earthing an oven.

Not if it were an electric oven. However, there was a day in which people may well have earthed a gas oven (even if there was nothing 'electrical' about it) - and, in such a case, I would certainly agree with you that it would have been safer not to earth it.

Kind Regards, John

 

[JohnW2]

As for drilling walls: use a cordless drill with the electricity switched off.

That's probably what I would do (if any of my cordless drills were man enough for the job!) - even though it carries the risk that damage to cables might go unnoticed.

However, so long as they are manufactured and sold, that has no bearing on the design of corded electric drills - which, as I said, one might feel warranted treatment as a 'special case'.

Kind Regards, John

 

[securespark]

Also, do not earth your cutlery.

Ahhhhhhh. I'm disappointed now.

 

[ade11]

My cordless certainly is not man enough for whatever the almost black,rock hard stuff is that lies beneath the plaster here,nor the stone on the outside. My Makita SDS is plastic bodied,my question was hypothetical,something that one of these new DIY enthusiasts might have done in the 60s after seeing an episode of Barry Bucknall.
I have removed the radiator bonding,and the dust,many thanks.

 

[JohnW2]

My cordless certainly is not man enough for whatever the almost black,rock hard stuff is that lies beneath the plaster here,nor the stone on the outside.

Similar here, hence my qualification that I only use a corded drill when a cordless one is not man enough for the job. In my house (a mixture of Georgian and Victorian), it is the 'plaster' itself that is the problem, and I have both the sublime and the ridiculous - some appears to have the characteristics of reinforced concrete, whilst the other behaves like sand - and neither is much fun to work with/on! I certainly have yet to come across any cordless drill which is in the slightest interested in the former!

My Makita SDS is plastic bodied,my question was hypothetical,something that one of these new DIY enthusiasts might have done in the 60s after seeing an episode of Barry Bucknall.

At least in my opinion, it was neither a hypothetical or a silly question. As I said, the situation is nearly always that of protecting people from live electrical parts within some item and, as EFLI has said, the approach of non-earthed (even if metal-cased) and double-insulated is then generally favoured. However, as I've said, I think that things like corded drills are a very special case since, fairly uniquely, they then come with a risk of 'becoming live' as a result in coming into contact with live parts outside of the item (in addition to the usual risks associated with anything which has live parts 'within it').

So, although it doesn't seem that EFLI agrees, if I thought that there was the slightest risk that I could drill into a live cable (which is a possibility I would obviously seek to avoid), in the specific case of a drill (or similar) I would personally be happier if any touchable metal parts (including chuck) were earthed (whether or not it was also 'double insulated' - and that would even remain the case if there was no RCD protection, since an MCB or fuse should normally respond to such a live-earth fault.

Like you, I do still have some (working, but very rarely used these days) drills of this type, like the one illustrated below - metal bodied, 'double insulated' and not earthed, with very low resistance between chuck and touchable metal parts of the body.

Of course, even if the body of a non-earthed metal-bodied drill becomes 'live' that, alone, will not result in an electric shock. For a shock to happen in that situation requires that one is simultaneously touching something else which IS earthed. That's why, as EFLI has said, it is, in general, undesirable to ('unnecessarily') earth metal-bodied double-insulated items - since if one touches one of them at the same time as touching, say, a 'live' drill body, one would get an electric shock that would probably not have happened in the absence of that ('unnecessary') earthing of the second item.

Kind Regards, John