[ARC5] Re-stuffed cap

[Kenneth G. Gordon]

Later this evening, I'll post the article and photos of my latest re-stuffing job 
to my website.

Although this first attempt looks "acceptable" and works well, it does not look 
as good as I think I can make them. I would like to make them look identical 
with the originals, but may not be able to.

I am working on another one, which, by the way, was made by Aerovox. The 
previous one was made by Sprague. Both appear to have been built 
identically, probably according to either A.R.C. or military specifications. 

However, the Aerovox cap was MUCH more deteriorated, both internally and 
externally, than the Sprague. All the individual caps in the Aerovox cap were 
completely "soaked" in green corrosion, and the connections to the ends 
were all loose. They ALL came loose with a very slight tug on the leads, and 
the interior of the brass pot was covered in green corrosion, which was very 
difficult to clean out.

I have tested the Sprague cap that I finished, and have found some 
interesting things: 

1) there is considerable capacitance measurable BETWEEN each of the 
three disk ceramics, even the "outside" two, in the restuffed cap: about 0.025 
mfd between EACH 0.05 mfd cap, almost exactly 1/2 of the capacitance of 
each individual cap. I installed all three disc ceramics "facing" the same way. 
In the next one, I'll reverse the center one to see if that makes any 
difference.

2) When measuring the originals, there was ALSO just about 1/2 the rated 
capacitance between each of the paper caps. I wonder if this was a 
"designed-in" feature of the original circuitry? If it was, i wonder what its 
purpose was intended to be? Maybe it doesn't matter? 

3) There is no measurable leakage at 450 VDC (the upper limit for my C-3) 
between any of the three caps. The capacitances between them, again 
0.025 mfd, have identical leakage as that of each individual cap....essentially 
none.

4) Although I did this first job in several sessions, I suspect that if I were to sit 
down and complete one, from start to finish, it would take a little over 1 hour 
apiece.

Does anyone know that these brass pots were plated with? Zinc? Some 
other metal?

Is it worth it? I don't know, but it is certainly interesting...

Ken W7EKB