A relative gave me a flaky table lamp to look at. It turns out that
it had a blown lamp & a loose connection in the lampholder. It also
had a semi-antique MK plug & zipcord (single-insulated 2-core flex),
which I said needed replacement.

http://www.ducksburg.com/diy/lamp-old-cable.jpg


The whole thing consists of alternating pieces of glass & plastic,
topped with a switched BC lampholder, all held together with a steel
tube threaded at both ends, with a nut on the bottom (inside the base)
& a knurled nut on top with an external thread that the lampholder
screws onto.

http://www.ducksburg.com/diy/lamp-bottom.jpg

http://www.ducksburg.com/diy/lamp-side.jpg

http://www.ducksburg.com/diy/lamp-top.jpg


In one of my boxes of crap^W surplus parts I found a double-insulated,
two-core flex cable that would fit through the pipe, but I'm concerned
about the lack of earthing on the pipe, the possibility that the
pipe's edges might damage the cable (at either end). (When the whole
thing is assembled, the only exposed metal is the nut & the end of
pipe in the base.)

Suggestions? (I doubt this is a valuable antique, so "chuck it
because it can't be done right" is a possible answer.)

Thanks,
Adam

On Fri, 11 Jan 2013 22:32:22 +0000, Adam Funk
wrote:

A relative gave me a flaky table lamp to look at. It turns out that
it had a blown lamp & a loose connection in the lampholder. It also
had a semi-antique MK plug & zipcord (single-insulated 2-core flex),
which I said needed replacement.

http://www.ducksburg.com/diy/lamp-old-cable.jpg


The whole thing consists of alternating pieces of glass & plastic,
topped with a switched BC lampholder, all held together with a steel
tube threaded at both ends, with a nut on the bottom (inside the base)
& a knurled nut on top with an external thread that the lampholder
screws onto.

http://www.ducksburg.com/diy/lamp-bottom.jpg

http://www.ducksburg.com/diy/lamp-side.jpg

http://www.ducksburg.com/diy/lamp-top.jpg


In one of my boxes of crap^W surplus parts I found a double-insulated,
two-core flex cable that would fit through the pipe, but I'm concerned
about the lack of earthing on the pipe, the possibility that the
pipe's edges might damage the cable (at either end). (When the whole
thing is assembled, the only exposed metal is the nut & the end of
pipe in the base.)

Suggestions? (I doubt this is a valuable antique, so "chuck it
because it can't be done right" is a possible answer.)

Thanks,
Adam

replace the plastic lampholder with a brass one, which will have an
earth terminal, and use 3 core flex

--
Graham.
%Profound_observation%

Assuming the tube has enough clearance for that ccable. I am sure I've seen
similar lamps with some kind of gunge, maybe silicon in the bottom of that
tube so the two core cannot get near the edge of the tube, kind of like a
diy grommet!

Brian

--
From the Sofa of Brian Gaff Reply address is active
"Graham." wrote in message
...
On Fri, 11 Jan 2013 22:32:22 +0000, Adam Funk
wrote:

A relative gave me a flaky table lamp to look at. It turns out that
it had a blown lamp & a loose connection in the lampholder. It also
had a semi-antique MK plug & zipcord (single-insulated 2-core flex),
which I said needed replacement.

http://www.ducksburg.com/diy/lamp-old-cable.jpg


The whole thing consists of alternating pieces of glass & plastic,
topped with a switched BC lampholder, all held together with a steel
tube threaded at both ends, with a nut on the bottom (inside the base)
& a knurled nut on top with an external thread that the lampholder
screws onto.

http://www.ducksburg.com/diy/lamp-bottom.jpg

http://www.ducksburg.com/diy/lamp-side.jpg

http://www.ducksburg.com/diy/lamp-top.jpg


In one of my boxes of crap^W surplus parts I found a double-insulated,
two-core flex cable that would fit through the pipe, but I'm concerned
about the lack of earthing on the pipe, the possibility that the
pipe's edges might damage the cable (at either end). (When the whole
thing is assembled, the only exposed metal is the nut & the end of
pipe in the base.)

Suggestions? (I doubt this is a valuable antique, so "chuck it
because it can't be done right" is a possible answer.)

Thanks,
Adam

replace the plastic lampholder with a brass one, which will have an
earth terminal, and use 3 core flex

--
Graham.
%Profound_observation%

On Friday, January 11, 2013 10:32:22 PM UTC, Adam Funk wrote:

A relative gave me a flaky table lamp to look at. It turns out that
it had a blown lamp & a loose connection in the lampholder. It also
had a semi-antique MK plug & zipcord (single-insulated 2-core flex),
which I said needed replacement.
http://www.ducksburg.com/diy/lamp-old-cable.jpg
The whole thing consists of alternating pieces of glass & plastic,
topped with a switched BC lampholder, all held together with a steel
tube threaded at both ends, with a nut on the bottom (inside the base)
& a knurled nut on top with an external thread that the lampholder
screws onto.
http://www.ducksburg.com/diy/lamp-bottom.jpg
http://www.ducksburg.com/diy/lamp-side.jpg
http://www.ducksburg.com/diy/lamp-top.jpg
In one of my boxes of crap^W surplus parts I found a double-insulated,
two-core flex cable that would fit through the pipe, but I'm concerned
about the lack of earthing on the pipe, the possibility that the
pipe's edges might damage the cable (at either end). (When the whole
thing is assembled, the only exposed metal is the nut & the end of
pipe in the base.)
Suggestions? (I doubt this is a valuable antique, so "chuck it
because it can't be done right" is a possible answer.)
Thanks,
Adam

If you're going to fit double insulated cable, the metal tube shouldn't need earthing, as long as the detailing's ok at the top it'll be class II. If the detailng's wrong, ie a stray flex end could touch the tube, the 2 flex ends can generally be tied together to solve the issue.

You may be able to get a small clamp inside the lampholder at the top, perhaps a cable tie if the flex is fitted in such a way that it doesn't rotate.


NT

On 2013-01-12, Brian Gaff wrote:

Assuming the tube has enough clearance for that ccable. I am sure I've seen
similar lamps with some kind of gunge, maybe silicon in the bottom of that
tube so the two core cannot get near the edge of the tube, kind of like a
diy grommet!

I don't think 3-core flex will fit through the tube or through the
notch in the side of the base (not clear in the photos) that lets the
base sit flat on a table if you pass the flex out the right way.