Ivory Kellogg 700A...The Saga Continues

[savageje]

I've started on the restoration of this interesting phone and thought I would post some more pictures.  Luckily, the glue holding the handset to the base turned out to be water soluble, so I was able to get the handset off of the base without further damaging either.  Amazingly the handset was still in one piece, and the base looks to be in perfect condition.  The receiver capsule looks pretty tired, as you will see below.  The transmitter capsule has some writing on it, which I can't quite make out, but it appears to have a name on it...looks like "Stanton." 

I think have a strategy on how to repair the handset, but it is going to take some time and extreme care to get it done.  I'll post updates as I can.

[savageje]

Sorry to reply to my own post...here are some more photos.  Forgot to mention that the hookswitch assembly was missing, and the replaced one you see in the photos I obtained from Kellogg Mike.

Jim

[LarryInMichigan]

Jim,

Does the hole in the handset go through either of the conductors?

Larry

[Jim Stettler]

Jim,
That lamp  looks much better as a telephone. I went back to the old thread and was looking at your before photo's.

The damage doesn't look as bad as it could of been.
Good luck on your repairs.
Jim S.

[savageje]

In response to Larry, from what I can see, the hole does go through one of the conductors, but not the other.  Since the conductors are molded into the plastic, I have no way of knowing where the other conductor rides within the handle.  I am going to experiment by trying to fashion a "plug" out of a piece of dowel rod with a thin band of conductive material around it to see if I can restore continuity to the broken conductor.  If I can get some variation of that fix to work, then it may be possible to fix the remainder of the damage to the handset with some kind of fill material.  Jim, thanks, I am pretty happy with the overall condition at this point.  It was a lucky thing that I was able to get the handset and base apart without further damaging either.

[LarryInMichigan]

Jim,

If you can fix the broken conductor, you can probably fill most of the hole with wood filler.  I do not know what you would use on the surfaces.  I am anxious to hear how it turns out.

Larry

[Dan/Panther]

If I were going to fix the broken wire I would very carefully try to expose more of the existing wire inside of the handset. then I would make the ends of the exposed conductor as flat as I could. then I would cut an appropriate sized piece of solid copper wire long enough that it would fit snugly between the ends of the exposed wire. THEN CAREFULLY AND QUICKLY solder where the ends meet, using a low wattage soldering pencil. NOT ONE OF THOSE CAVEMAN SOLDERING GUNS. Just take care not to get every thing too hot for obvious reasons, even if you do it will not harm the outside of the handset.
Just my 2 cents worth.
D/P

[savageje]

D/P:

Thanks for the suggestion.  I think that approach makes sense to repair the conductor.  It will probably be a couple of weeks before I attempt to repair the handset.  I've been taking my time on this one, since the phone and the damage are so unusual.  I felt like I was on top of the world when I managed to get the handset off the base -- I want to savor that feeling for a while before moving on to the next nail-biting phase of the repair.   

[JorgeAmely]

There is a lot of mass in that handset. The conductors are thick and the plastic of the handset will act as a heat sink. Plan to spend some time heating up the wire ends before solder can melt and cover the wire. It will help if you can apply flux to the wire before heating it.

If only one of the wires is exposed, you may try to create a floor with epoxy, then another layer of conductive epoxy to cover the exposed severed lead and another final layer of epoxy to seal the hole. So essentially, you end up with an epoxy sandwich with a conductive layer in the middle. I would experiment with what type of resistance you can tolerate in the speaker, since conductive epoxy, although low in resistivity, does not behave like the metal long gone.

Check out this site:

http://www.mgchemicals.com/products/8331.html

[Dan/Panther]

Jorge;
I didn't know they made conductive epoxy. On an ohm meter will it zero out or show resistance on say the 10,000 ohm scale ?
D/P

[JorgeAmely]

D/P:

There are many kinds of conductive epoxies, but this one in particular seems very good for this application. If you had a small block of 30 by 25 by 1 mm, the expected resistance would be 2.5 ohms. Not bad in my opinion. In this application, it could be less, since the conductors are closer than 30 or 25 mm.

However, I suggest inserting a 2.5 ohm resistor in series with the receiver to see how good it works. Increasing the area of the exposed copper wires will bring the resistance down. With an ohm meter, once the epoxy cures, the meter will get close to zero (in this example, 2.5 ohms), depending on the meter scale.

My 2 cents.