The process of re-forming caps does work; the problem you may well run into is the fact that quite often the caps have dried up over the decades as they are not perfectly sealed. In some cases if you look at the bottom of them, you may find that they are bulging- you can count on these to form up properly about as much as you can count on a bulging tire on your car. I would only attempt to re-form a cap that shows no sign of damage due to age or heat.
The half life of filter caps in round numbers is about 20-25 years, which is to say that in that time about half of them will have failed. In an amplifier like this that is more like 50 years old, harboring the idea that some of the filter caps might still be good after that time is simply asking for trouble.
The half life of filter caps in round numbers is about 20-25 years, which is to say that in that time about half of them will have failed. In an amplifier like this that is more like 50 years old, harboring the idea that some of the filter caps might still be good after that time is simply asking for trouble.