The unit is close to being completed here. The back panel was removed and cleaned. The RCA jacks were all polished. I did not
take photos of the that step. Fairly straight forward and I have covered that in detail in other write-ups. What remains is the
replacement of the main supply capacitors. The object here is to stuff the original cans with a new set of capacitors. The
progress of time has produced smaller and smaller capacitors. It is difficult to find capacitor in the large sizes these days. When
you do they are often very costly. But, the smaller one that are widely available offers a nice work around, as we can use the
original cans.
take photos of the that step. Fairly straight forward and I have covered that in detail in other write-ups. What remains is the
replacement of the main supply capacitors. The object here is to stuff the original cans with a new set of capacitors. The
progress of time has produced smaller and smaller capacitors. It is difficult to find capacitor in the large sizes these days. When
you do they are often very costly. But, the smaller one that are widely available offers a nice work around, as we can use the
original cans.
I have done a lot of can stuffing. I have found the easiest way is a follows:
1) Cut the crimp off the original cans using a cutting wheel and a dremel tool.
2) Pry up the contact base and free it from the can.
3) clean up the can edge using a file and a bit of sand paper.
Just flatten the edge and soften the edges of the cut with the sandpaper.
4) Clean the can out.
Place the can in hot watter for a few minutes. This soften the wax.
Use needle nose pliers to pull the core out of the can.
Use an old screw driver to scrape the wax from the can. You don't need to get all of the wax out, just the bulk of it.
There is always some residue... just leave it).
5) Mount the new capacitor to the contact base.
I drill small holes in the lead rivets, just large enough to pass 20ga. wire through.
Mount negative to negative and positive to positive so that the old contact base reflects the proper polarity of the new
capacitor ( i.e., "negative black").
Solder a length of wire to the posts of the new cap and pass the wire through the holes in the old contact base.
Wrap the wire around the contact and solder.
Pack some reinforced epoxy between the new capacitor and the underside of the contact base (around the posts).
This give a solid joint between the two part.
6) Insert the new capacitor into the old cans.
I put a small amount of expanding foam in the bottom of the old can just before inserting the new cap.
Just a small amount. This will provide a solid footing for the new capacitor to rest on and secure the new cap in the
can. I also put a small amount of epoxy around the inside lip of the can (i.e., the foam glues the new capacitor down
and the epoxy glues the contact base in.
1) Cut the crimp off the original cans using a cutting wheel and a dremel tool.
2) Pry up the contact base and free it from the can.
3) clean up the can edge using a file and a bit of sand paper.
Just flatten the edge and soften the edges of the cut with the sandpaper.
4) Clean the can out.
Place the can in hot watter for a few minutes. This soften the wax.
Use needle nose pliers to pull the core out of the can.
Use an old screw driver to scrape the wax from the can. You don't need to get all of the wax out, just the bulk of it.
There is always some residue... just leave it).
5) Mount the new capacitor to the contact base.
I drill small holes in the lead rivets, just large enough to pass 20ga. wire through.
Mount negative to negative and positive to positive so that the old contact base reflects the proper polarity of the new
capacitor ( i.e., "negative black").
Solder a length of wire to the posts of the new cap and pass the wire through the holes in the old contact base.
Wrap the wire around the contact and solder.
Pack some reinforced epoxy between the new capacitor and the underside of the contact base (around the posts).
This give a solid joint between the two part.
6) Insert the new capacitor into the old cans.
I put a small amount of expanding foam in the bottom of the old can just before inserting the new cap.
Just a small amount. This will provide a solid footing for the new capacitor to rest on and secure the new cap in the
can. I also put a small amount of epoxy around the inside lip of the can (i.e., the foam glues the new capacitor down
and the epoxy glues the contact base in.
