Despite having over 50 years' experience a ham, as a non-smoker my own gear (and I never get rid of anything) has not had to bear the horrors of nicotine & tar contamination. I *have* used the ideas in this and similar threads for repairing vintage (like 60s) guitar & bass amplifiers.
I've seen product names bandied about with which I have zero experience, but a couple with whom I'm pretty familiar as to desirable and undesirable effects on components and cases, plastics, etc.
Buying isopropyl alcohol can be a matter of shopping several pharmacies. Nearly everyone sells ~71% isopropanol, but the thing to remember is that the percentage that *isn't" alcohol is water. I generally shudder at using low percentage alcohol on components or areas of chassis/panel/etc to which I will not later have access to apply something which will remove the water content.
Finding 99% isopropyl alcohol usually entails a conversation with a pharmacist. I think it's partly to assure the guy/gal in the white coat that it's not going to be going into a beverage. Not that it would be germane to the topic at hand, but watch their eyebrows if you ask for potassium chlorate or potassium permanganate......
"Absolute ethyl alcohol" is another good choice for simply cleaning, but it's only 100% with the bottle closed. As soon as the bottle is opened in normal atmosphere, the hygroscopic character of the alcohol will, if left open, absorb (adsorb? I can't remember the right term) atmospheric water until the solution is 95% ethanol and 5% water. That's usually fine for cleaning, as a little heat from a hair dryer will eventually drive out the water, and make the component ready for some DeOxit. FWIW, if you live in a state where 190 proof Everclear beverage is available, there's your 95% ethanol/5% water mixture in a convenient (if somewhat expensive) container. If it stays away from gullets and open flame, it should last awhile as a cleaner.
Caig's DeOxit comes in several versions, and there's a big difference in their delivery vehicle(s). If the label says "D100", than the contents is 100% DeOxit, which both cleans contacts AND leaves a lubricant & contact "enhancer". I flunked Physical Chemistry in college, so I don't know just what it is that can enhance conductivity without itself being a conductor of electricity. After, I are not an en-gunn-ear; mayhap others can weigh in on this. I've got two 15ml bottles with nail polish-like brushes. Along with a nearly inexhaustible supply of Q-Tips, and very sparing application of the DeOxit, these two bottles should last until my progeny takes over the shack/bench.
They also have a spray version of DeOxit, which is 5% DeOxit and 95% vaporizing diluting agent and propellant. I have a 2 ml vial of D100 in my bass gig bag for treating guitar cable plugs and, upon insertion, their jacks. For getting DeOxit into pots that have very small openings into "the guts", the 5% spray with its teensy straw can usually get a short blast inside, to be followed by sometimes-heroic rotation of said pot from stop to stop to de-gunk as much of the wiper and substrate as possible. I use that method as a quick diagnosis of a part (pot, slide switch, jack, etc.) that needs to be replaced after the next gig, as usually they're already on their way out and are relatively inexpensive.
For tube pins and sockets that are likely to be exposed to temperatures nearing (or exceeding) 240 deg C, Caig's Gold product is a product that doesn't turn to varnish. I've had a 15 ml bottle of 100% solution on the bench that's lasted over 4 years. They also have a couple products, GxL and Gx2, both of which are good to over 500 deg C, but are only available as samples to the aerospace industry. I haven't yet figured out how to ask for a sample to rebuild my current Viking I mxtr, and my "point & click" IR detector says the tubes in the Viking and my Amplidyne 621 run well under 190 deg C, so I'm probably good with the "regular" Gold product. Note that the Gold products yield only about 0.5% cleaning action; the rest is intended to function as a noble metal to noble metal (ideally gold) contacts.
Caig also has a specific lube product for conductive plastic components, like mixer faders, and is available as either a syringe loaded with light green grease, or as a much thinner spray product. I've tried it on conventional silver wiper/deposited carbon layer on a phenolic substrate pots with only limited success. It's hard to find a product (at least for me) that's good as a pot lube that also helps keep the contacts shiny and low resisitance.
YMMV may vary, of course. It's only been the past ten years that I've been reacquiring boatanchors made back when I got my first Novice ticket back in 1961 when I was 9 years old.
Oh -- almost forgot. My smarter half, a/k/a She Who Must Be Obeyed, repairs sewing machines. A class she attended espoused the Tri-Flow liquid with the straw for bearings, and their grease for gears. A single application on the two-position rotary switch switch that chooses the antenna output or the internal dummy load on my Amplidyne 621 turned the switch to being too locked in one position to turn with a Vise-Grip® to being able to turn it with the stock 1-1/4" diameter knob. Caig D100 on the terminals fixed the varying output through the switch.
This forum has taught me so much, and I'm hard pressed to express my thanks to all who have given their methods of getting this gear that's as old as I am back to working form. My only way to say thanks is to submit my own meager experience in the topic at hand.
73 es tnx
-- Stuart -- originally wn4ant (in 1961)