1960's "Lampette E-6" Telescoping Desk Lamp

Does anyone here have any experience repairing 1960's vintage "Lampette E-6" desk lamps (like the one pictured at:

)?

I have two of these lamps. One works well, but the other one only lights intermittently because of what surely seems to be a problem in the telescoping arm mechanism. Specifically, it only lights when I apply tension to the first (lowest) moveable telescope segment, and only then when the arm is no more than about 30 degrees from the horizontal. There are a couple of millimeters of "backlash" in that lowest segment of the faulty lamp that isn't evident in the one that works well.

I think I could probably figure out and fix whatever the problem is, if I felt like I could open up the telescoping mechanism without more or less destroying it. In general it doesn't appear that these lamps were designed to be serviced -- their assembly seems to have been something of a "one-way" operation. I've managed to get the base open by prying off the aluminum bezel at the bottom, and I've managed to get the arm disconnected from the plastic case. But that's where I'm stalled.

Anyone been down this road already?

Thanks,

Michael

++++

If the base does not contain a transformer, its probably a death trap anyway

The base *does* in fact contain a transformer that steps down from 110vAC to

6.2v, or at any rate, to a voltage that the model 1133 bulb (rated at 6.2v) can handle. M

desk lamps (like the one pictured at:

)?

intermittently because of what surely seems to be a problem in the telescoping arm mechanism. Specifically, it only lights when I apply tension to the first (lowest) moveable telescope segment, and only then when the arm is no more than about 30 degrees from the horizontal. There are a couple of millimeters of "backlash" in that lowest segment of the faulty lamp that isn't evident in the one that works well.

like I could open up the telescoping mechanism without more or less destroying it. In general it doesn't appear that these lamps were designed to be serviced

-- their assembly seems to have been something of a "one-way" operation. I've managed to get the base open by prying off the aluminum bezel at the bottom, and I've managed to get the arm disconnected from the plastic case. But that's where I'm stalled.

The lamps I've seen like that are made like a telescoping radio or TV antenna. They are heavier to support the weight of the lamp, and to allow a wire to be run to the lamp. The tubing is used for the other conductor.

They have a small amount of grease on the sliding contacts, near the top of each section of the tube. The bottom of each additional tube is flared enough to keep the tubes from wobbling. Other than good contact clearner, there isn't much you can do, if you don't have the tools and materials to make a replacment assembly.

E-6" desk lamps (like the one pictured at:

)?

intermittently because of what surely seems to be a problem in the telescoping arm mechanism. Specifically, it only lights when I apply tension to the first (lowest) moveable telescope segment, and only then when the arm is no more than about 30 degrees from the horizontal. There are a couple of millimeters of "backlash" in that lowest segment of the faulty lamp that isn't evident in the one that works well.

I felt like I could open up the telescoping mechanism without more or less destroying it. In general it doesn't appear that these lamps were designed to be serviced -- their assembly seems to have been something of a "one-way" operation. I've managed to get the base open by prying off the aluminum bezel at the bottom, and I've managed to get the arm disconnected from the plastic case. But that's where I'm stalled.

Agreed. If you cannot access the secondary side of the transformer perhaps add a mains carrying thermal fuse in contact with transformer if there is not one, and add a very low current normal fuse in the situation where the central conductor insulation perishes (often rubber in th e60s) and shorts the transformer.

=20

Yes, precisely so, although in this case, all but the topmost segment have = a square cross-section.=20

Actually I'm fairly certain that there isn't a "wire" (as such) inside the = tubing. The topmost telescope segment, the one with the round cross-section= , allows the lamp head to swivel 360 degrees, and there's no tactile or aud= ible evidence of any kind of wire getting wound up or binding inside the tu= bing.=20

Certainly there has to be some kind of central conductor, but I think it mu= st be a more mechanically rigid contrivance than just a plain old wire. The= re *is* an actual wire coming from the transformer secondary that enters th= e base of the telescope through a grommet that makes up part of the hinge o= n which the arm rotates to change angle. But I think that wire must be atta= ched to something mechanically stable inside the telescope, because it does= n't wiggle a bit when I either extend or retract the telescope tubing, or c= hange the hinge angle.

Hmm, "sliding contacts": presumably you mean contacts for the conductor tha= t's internal to the tube, right? If so, is it reasonable to think that the = primary problem is that the grease has been displaced enough to cause the i= ntermittent continuity problem?

Well, sure... but at the moment the problem is that I can't figure out a wa= y [1] to get at the internals of the telescope mechanism to apply the clean= er. If I can figure out how to do that (or someone here tells me the secret= to the puzzle!), then presumably I'll need to apply a new coating of greas= e after using the contact cleaner. Any recommendation on a good brand of gr= ease to use for this application?

[1] Other than possibly a high-speed cutting disk, which will make reassemb= ly a bitch. M

e s

Access to the transformer is not a problem: once the base/case is open, the= transformer is fairly easily extracted from it. And in any case, there is = a conventional-looking glass-tube fuse between one of the secondary termina= ls and the outer part of the hinge mechanism, which is in electrical contac= t with the the telescope tubing. So the shorted secondary case is covered.

If I were to add the thermal fuse as suggested, is there a simple way to es= timate the target temperature rating? The formulae I've seen for estimating= transformer temperature rise involve a lot of parameters (flux density, co= re material constant, etc.) whose values I wouldn't know how to obtain.

(FWIW, I've never found the cases on either of these lamps becoming noticea= bly warm, even after many hours of operation.)

M

transformer is fairly easily extracted from it. And in any case, there is a conventional-looking glass-tube fuse between one of the secondary terminals and the outer part of the hinge mechanism, which is in electrical contact with the the telescope tubing. So the shorted secondary case is covered.

estimate the target temperature rating? The formulae I've seen for estimating transformer temperature rise involve a lot of parameters (flux density, core material constant, etc.) whose values I wouldn't know how to obtain.

warm, even after many hours of operation.)

I see no need to add the thermal fuse. There is probaby one inside the transformer to prevent a fire.

square cross-section.

tubing. The topmost telescope segment, the one with the round cross-section, allows the lamp head to swivel 360 degrees, and there's no tactile or audible evidence of any kind of wire getting wound up or binding inside the tubing.

It wouldn't be 'wound up'. It wuld simply run through the tubing, like wore in conduit.

be a more mechanically rigid contrivance than just a plain old wire. There *is* an actual wire coming from the transformer secondary that enters the base of the telescope through a grommet that makes up part of the hinge on which the arm rotates to change angle. But I think that wire must be attached to something mechanically stable inside the telescope, because it doesn't wiggle a bit when I either extend or retract the telescope tubing, or change the hinge angle.

it would make more sense for extra wire to go into the top piece, rather than into the base.

internal to the tube, right? If so, is it reasonable to think that the primary problem is that the grease has been displaced enough to cause the intermittent continuity problem?

NO, I mean the the return is the metal arm. Test it with a meter, between the top section and the lowest section and wiggle it to make it go on & off to see if yoou read a voltage across the tubing. At that age it's possible the internal wire has hardened and broken, and only works when in the right postion.

[1] to get at the internals of the telescope mechanism to apply the cleaner. If I can figure out how to do that (or someone here tells me the secret to the puzzle!), then presumably I'll need to apply a new coating of grease after using the contact cleaner. Any recommendation on a good brand of grease to use for this application?

Spray it above the opening where they overlap, and let it run down into the lower tube. You don't need much. If you do, it's beyond repair.

a bitch.

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From the movement of the telescopic section, most likely the wire inside is damaged. It will be a bit of a job to fix this. un-assemble the lamp. Remo ve the wire inside of the telescopic section. Find an adequate wire replace ment, and replace it. If I remember correctly, this will involve some solde ring to replace the wire.

Jerry G.

-6" desk lamps (like the one pictured at:

)?

intermittently because of what surely seems to be a problem in the telescop ing arm mechanism. Specifically, it only lights when I apply tension to the first (lowest) moveable telescope segment, and only then when the arm is n o more than about 30 degrees from the horizontal. There are a couple of mil limeters of "backlash" in that lowest segment of the faulty lamp that isn't evident in the one that works well.

felt like I could open up the telescoping mechanism without more or less d estroying it. In general it doesn't appear that these lamps were designed t o be serviced -- their assembly seems to have been something of a "one-way" operation. I've managed to get the base open by prying off the aluminum be zel at the bottom, and I've managed to get the arm disconnected from the pl astic case. But that's where I'm stalled.

desk lamps (like the one pictured at:

)?

intermittently because of what surely seems to be a problem in the telescoping arm mechanism. Specifically, it only lights when I apply tension to the first (lowest) moveable telescope segment, and only then when the arm is no more than about 30 degrees from the horizontal. There are a couple of millimeters of "backlash" in that lowest segment of the faulty lamp that isn't evident in the one that works well.

like I could open up the telescoping mechanism without more or less destroying it. In general it doesn't appear that these lamps were designed to be serviced

-- their assembly seems to have been something of a "one-way" operation. I've managed to get the base open by prying off the aluminum bezel at the bottom, and I've managed to get the arm disconnected from the plastic case. But that's where I'm stalled.

As I recall that lamp used a single wire inside the tube, with the tube itself being the second lead. So if the tube is not making a good electrical connection at the hinges it won't work reliably.

Pretty sure there is a transformer in the base and a 12or 24V bayonet base lamp. These things were sold in Canada and CSA regulations would not allow for a hot chassis lamp!

John :-#)#

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desk lamps (like the one pictured at:

)?

intermittently because of what surely seems to be a problem in the telescoping arm mechanism. Specifically, it only lights when I apply tension to the first (lowest) moveable telescope segment, and only then when the arm is no more than about 30 degrees from the horizontal. There are a couple of millimeters of "backlash" in that lowest segment of the faulty lamp that isn't evident in the one that works well.

felt like I could open up the telescoping mechanism without more or less destroying it. In general it doesn't appear that these lamps were designed to be serviced -- their assembly seems to have been something of a "one-way" operation. I've managed to get the base open by prying off the aluminum bezel at the bottom, and I've managed to get the arm disconnected from the plastic case. But that's where I'm stalled.

This is a three month old thread.

E-6" desk lamps (like the one pictured at:

)?

intermittently because of what surely seems to be a problem in the telescoping arm mechanism. Specifically, it only lights when I apply tension to the first (lowest) moveable telescope segment, and only then when the arm is no more than about 30 degrees from the horizontal. There are a couple of millimeters of "backlash" in that lowest segment of the faulty lamp that isn't evident in the one that works well.

felt like I could open up the telescoping mechanism without more or less destroying it. In general it doesn't appear that these lamps were designed to be serviced -- their assembly seems to have been something of a "one-way" operation. I've managed to get the base open by prying off the aluminum bezel at the bottom, and I've managed to get the arm disconnected from the plastic case. But that's where I'm stalled.

Yup. I read it too.