[ARC5] Flower pot cap restoration

[Brian Clarke]

My solution was to use a very fine parting-off tool in a lathe: chuck-up the 
capacitor body, and then part off just below the swaged lip. A hacksaw blade 
could do the job, but flying lathe chuck parts make that less safe than 
using the micrometer-driven tool-post.

After sucking off the solder from the grounding connection, a little heat 
from a small flame torch (not enough to discolour the outer 'skin') and the 
defunct capacitors came flying out.

After restuffing with 400 Vdc capacitors, I soldered the swaged lip directly 
to the body and wiped off the extra solder, just like an olde tyme plumber 
would have. And you can't see where I've been unless I tell you. I found no 
need to add spaghetti to the capacitor leads - they are far enough apart.

Some Sprague-marked capacitors had a terminal plate soldered onto the 
cylindrical body. Terminals came through rubber or fibre feed-throughs - 
obvious path for dehydration or gassing out. But no need to chuck in the 
lathe - just unsolder the grounding wires, apply torch heat to the lip and 
then the body of the capacitor. It's a safe practice to wear closed shoes to 
avoid hot solder causing you to attempt St Vita's dance.

BTW, I didn't pot the replacement capacitors with epoxy or wax - I was 
thinking of the next maintenance person.

73 de Brian VK2GCE.

On Saturday, June 21, 2014 3:37 PM, Neil said:


>A little inward bevelling (with a file) on the mating edges of both parts
> might create a little "trench" around the perimeter when they are fitted
> together and give the solder somewhere to sit. Maybe the excess solder 
> that
> rises above the trench could be ground off or machined off.