Mickey2

It's a very nice find. The safest way is of course sewing machine oil, and usually the grimiest machine cleans up with persistance and patiences; sacrifice a few of those velvety microfiber cloths, apply sewing machine oil and lots of swirly movments and gentle rubbing should get you far.

I have to admit I have used microfiber cloths, lukewarm water, and even a bit of soap (well wringed up) on machines with the shellac in good condition. I have been lucky and no damage to decals or shine (these were later 1930s and 50s machines). I know they used to recommend wiping off wooden furniture with shellac finishes with a damp goat skin, and I assume microfiber cloths are a good alternative these days. The idea is not to leave any moisture on the finish. I start with the gentlest alternative and advance from there if needed. I have never used anything very harsh, and even the worst of grime have come off.

Shellac is often surprisingly restistant to time and grime, and cleands up very nicely. A resin type car polish will further clean, polish and protect. Swirly movements with car polish should lift up the last remains of dirt. Once cleand and polished a gently wipe is all I have needed to keep my machines clean, I give it polish every other year or so, even less frequent (again, resin type car polish).

Inspite of the dirty and dull surface, your machine looks very nice and not much wear to the surface and decals at all. The shiny metal bits I clean with a cream type metal polish, even rods, parts under the base. I take of needle clamp and presser foot, apply polish to strips of cloths or cotton fabric; I hold on to each end of the strip, wrap it around the bars and rods and pull back and forths. Usually the metal shine up like new.

What I usually do first is lubriate all oil points, and cleaning the feed dogs and bobbin area, take of the face plate, throat plate, bobbin plate, take the bobbin case out. Underneath there are two black caps, each covering a set of meshing gears; I unscrew those (held in place by three screws), clean and oil them. The 201-2 needs to have the upper gears near the motor and hand wheel cleaned and greased.