Depending on what you're working on, IMHO, the squig technique is viable.
(Cut the leads as close to the component body, bend the lead so
they're pointing out, make a squig on the new component leads, place
over the old leads, solder with regular solder.)
See:
For more (not my) details.
On Fri, Mar 1, 2024 at 3:03?PM Ed Breya via groups.io
<edbreya@...> wrote:
You definitely want to use a silver bearing solder (about 2-3%), if you want to preserve the contacts. In an emergency repair, you can use use regular solder, but it will degrade it almost immediately, and the Ag will lose its bond to the porcelain. It's not the end of the world - as long as the part leads are all in place, they will solder together and work just fine, but lose some of their mechanical support, and it looks ugly.
The iron needs to have enough power (around 40-60 W is good), and a chisel tip thin enough to go into the slot, like a screwdriver. Don't pry on it of course, since the porcelain can easily chip or crack. Feed the solder to the flats on the tip and the slot at the same time. Be aware that even with the right solder, if you overheat it enough, it will degrade too. You have to know when to ease up and let it cool, then try again. Practice makes perfect. I think all the old scope manuals should have a section on the right stuff to use, and proper techniques, so use that for reference. I think it's basically as I described.
I have lots of the ceramic strips salvaged from old Tek gear, a couple old-school 50 W irons and tips, and a couple pounds of Ag-solder, all set aside for only this kind of work. But, I wouldn't use the strips for routine circuit construction - too much grief. It's only for repairs on existing gear, or building high voltage or high temperature circuits.
Ed
