How best to clean old 78s.

Well, this is the first time I'm posting in the analog forum. I was wondering if you could help a poor, unenlightened digital format guy.

A friend of mine knows someone that has inherited a collection of old 78 records from circa 1920. They had been stored away, but like anything that's been in existence that long [I guess that would include my dad] they're not in optimum playing condition.

Can you offer some recommendations as to how to clean and/or to a certain extent restore these old records? Would it be much different from your regular cleaning routine?

I apologize for the vague question as I don't know the exact condition of these 78s. I'm told they probably won't be played back on a high end system either.

Thanks in advance,
This might be quite an adventure! First of all you cannot be sure of what you have. And you would not want to play them on a high end system unless you have a 78 cartridge such as Shure is making. So, begin with examination. Are they gritty grimey? Then start with a nice wash under the tap. No rubbing! Are they just dirty, then use purified water liberally. You can use clean dish towels as a work surface and the great brushes that Disk Doctor makes. You are going to need his cleaning consentrate anyway (no alcohol!)so you may as well just order his whole kit with a pint or quart of fluid. Are they mildewed? Then you need an enzyme cleaner. Try Bugtussel. After you do the prelim wash(es), you are ready to use the good Doctor's fluid and brush for the clean. Change base towels as needed. He encloses comprehensive directions so I will not repeat. Just know that nothing else is as good, safe or easy as DD. Do the final purified water rinse and dry. Then use Last record preservative. You will see the surface drink it in. It seals without sonic residue. It reduces friction to put less wear on the stylus and less noise in the play. A clean new sleave, preferably acid free paper, and you are done. Best wishes. It ain't digital, but it has a sound of its own which has an artful immediacy.
"Artful intimacy" from the guy who gave us "toothsome"! We have a poet! Keep'em coming, Aceto, a good antidote to what confronts us on television these days...
I use Record Research Labs cleaning fluid on my 78 RPM jazz records. Safe and very effective.
At least get a turntable that can handle a modern cartridge, so you don't ruin the records. There are a few budget cartridges that still have 78 styli available.

Ortofon OM stereo cartridges start at $25; the 78 styli is another $39. This way you can play regular LP's with the same cartridge.

The Shure 78 cartridge is the M78S for $59.

Stanton and Grado also offer 78 styli for some model cartridges.

Try for any supplies, cleaner, cartridges, styli.

Dual Turntables from Germany are decent. Many play at 78 speed. Many used ones available really cheap on eBay. I have a Dual 1219 that I use for 78's and for poor condition 45's and 33's that I just want to listen to.

If the records are very dirty, then maybe warm water with a little dishwashing liquid to start off, before professional cleaner for deep cleaning.
These things are tough and there's no need to be gentle with them. I use a large old toothbrush on the worst of them with diluted Dawn dishwashing liquid and scrub the heck out of them, following the grooves. Then I rinse them under the tap and do a final rinse on my Nitty Gritty using distilled water. For 78s that look to be in basically clean shape, I just use VPI fluid in the Nitty Gritty with no rinse (at least until I play them and see if additional cleaning is necessary). I have three 78 rpm styli/carts: Grado, Stanton 881, and Shure. Soundwise, they rank in that order. The carts sound unbelievably better if you strap the two hot pins and two ground pins with very thin wire, holding it on with the cartridge leads. This can virtually eliminate surface noise on 78s in decent shape. I have many 78s that sound better than the same music on LP and CD -- this can be a jaw-dropping comparison. BUT WHATEVER YOU DO, DON'T USE ALCOHOL ON 78S -- IT WILL DISSOLVE THEM. Good luck, Dave
Afterthought: When I say they're tough, that doesn't mean you can handle them without being mindful of one thing.

They're not vinyl. They break.
Thanks so much for your recommendations! My friend is passing this thread and your great responses to the owner of these old records.

Happy listening!