[Milsurplus] Recovering "Bumble Bee" Capacitors

[John Hutchins]

All -
In the trade these are called BARCS, for Bake recoverable parts.

Hutch

> David Stinson wrote:
>    
>> At a recent hamfest, I bought a large bag of NOS Sprague
>> .1 uFd, 400 volt "Bumble Bee" capacitors, the ancestors of
>>   the "Black Beauty" type, for $3.
>> All of them were, of course, leaky to one degree or the other.
>> I took a handful of the worst leakers and put them in the stove
>> at 250 degrees for one hour.  The cases split, of course,
>> and a small amount of wax pooled under them.
>> I let them cool overnight and checked them again.
>> To my surprise, they check excellent!  Every one of them
>> came back.  At full voltage, they are in spec for capacitence
>> and leakage is less than 10-20 microamperes at 400 volts.
>> Of course, with the cases split, they'll absorb water again.
>> I'm thinking of resealing with liquid tape or the like.
>> I have quite a few more of them left.
>> Perhaps if I use a lower temp and longer time,
>> I can "dry" them without splitting the cases.
>>
>> 73 Dave S.
>>
>>