I use a double boiler which consists of a hot plate , with a pot of water and a soup can with wax in it. as I replace the paper caps I let them sit in the molten wax a minute, then just use a pencil to push out the guts from the paper tube.
and then I put the new caps inside. usually I splice on thicker wire to mimic the old ones solder the splice and hide the splice inside. . lots of new caps have thinner wire. I stuff a little kleenex in the end of the tubes hiding the new cap and put a bit of hot melt glue in the ends to seal it up. when done that I return them to my molten wax for a dip.. a lot of those old caps have beeswax so I just keep the same wax going to let it discolor a little and to let it accumulate some of the beeswax.
I like doing it that way as it preserves the labels. I’ve even found I can drill out the old black beauties and do the the same way. someone might come along and clip them all out at some point but it’s worked for me. If you want to be so ahem..-retentive , you can too.. 😉 of course if you do a really perfect job you can revel in the fact that no one notices your work, as is the case with most good restoration. Especially here because they are usually hidden below chassis anyway.
if you are having fun it’s ok, Some like to stretch out the fun a little longer 😉
if you ever go to work on electric motors, sometimes you’ll see the spaghetti used there to cover up the wires from the field windings to the little connection box. i found some on ebay a long time go and still have most of it. You can usually reuse it and sometimes its handy to have some of the thinner stuff to cover wires from capacitors and stuff.. or maybe wires that do show like to grid caps on tubes. as a last resort you might ask if you have a motor repair shop. maybe they buy new spagetti. It might be better under heat and vibration.. it looks a bit more original than heat shrink.
some of the heat shrink has sort of like glue inside it. there are different types and colors.
a source of rubber coated wire is from AC wire ( cabtire) the black heavy rubber coated cord used in commercial electrical wires. the most common is white red black and green. the red is usually a bit more pink than red. I think its OK but it isn’t really the most durable insulation. sometimes if you cut just a few inches you can pull the old wires out of the rubber sheathing and then stick your solid wire inside it. an example is to cover an inch of wire between a cap and where it is connected. if you do this ,you can be sure the wire now has no real CSA rating since you messed with it so use caution and common sense of course. the meter lead wire has a good resistance I think 600 volts and the wire inside is many strands of soft coppper so it will work in pretty much any radio application with perhaps a wider safety margin. I dont; like plastic wire , its too easy to melt it accidentally with a solder gun though in reality its probably quite safe. it kind of glares at your work like the yellow caps and jelly beans do. In most cases probably safe enough just not my favorite so far as original looks.
a lot of the parts in old radios were way overkill and probably most of the wire is ridiculously huge when you consider the amps it is carrying but there isn’t enough used to consider trying to work though ohms law and compare the load and wire size to save wire cost. , Instead we use wire and insulation that is way too heavy so that in some instances where the insulation rating is important , it is good enough. I think once we’ve made any changes to the wiring we have also required our work to be re certified by CSA , like if you were to try to use an old radio in a business or commercial setting they may want it re certified to have a valid CSA stamp and that would be interesting 😉 Care homes usually have a requirement that they need to inspect any electrical devices that you take to residents. I’ve often wondered what they would think of an old radio that was restored.
Phil
