https://www.austintypewriterink.com/typewriters-201-general-maintenance.html

Fossilized Masking Tape Removed Cleaned from Typewriter Body by [[Phoenix Typewriter]]

The paint on the metal of the SMC 6 series typewriters will generally stand up well to lacquer thinner and along with scratching can be used to remove the old residual masking tape often found on these typewriters.

WD-40, gun bore cleaner, and Simple Green generally don't do much to this sort of tape residue.

Royal Futura 800 Typewriter Plastic Key Top White Crud Removal Cleaning Servicing by [[Phoenix Typewriter]]

For the white, crusty out gassing (or off gassing) on plastic typewriter keys, Duane recommends a round or two of Simple Green with a stiff bristle brush. Follow this up with a scrub down using WD-40 to displace the water from the Simple Green and then follow up with denatured alcohol, which is safe on plastics, and a wipe down with a rag to dry.

The case FOR WD-40 use in typewriters by [[Thom Cholowski]] in Antique Typewriter Maintenance Group

Some thorough colloquial and unreferenced, but reasonably scientific advice about the use of WD-40 to clean typewriters, particularly with respect to water displacement.

Once used for cleaning typewriter internals, WD-40 needs to be flushed out with kerosene or naphtha.

Underwood Typewriter Black Matte Paint Wash & Shine Process Clean Restore Luster No Decal Damage by [[Phoenix Typewriter]]

How Duane cleans black matte paint and crinkle finished typewriters: Simple Green and a stiff brush, dry, then finish off by brushing in oil or WD-40 and wiping down.

Olympia SM Typewriter Wash, Scrub Clean Lid Cover, Restore Paint by [[Phoenix Typewriter]]

Simple Green gets off most dirt and nicotine as well as some White Out. Duane uses Nu-Trol Control Cleaner (for electronics) as a mild specialty cleaner for tougher White Out cleaning.

https://www.youtube.com/watch?v=EbGUVjOF2uw

He still seems iffy about the value of using WD-40 on crinkle cut finish, primarily because of the smell.

Others use brass bristle brushes for applying the WD-40 instead of nylon brushes.

WD-40 for Crinkle Finish Typewriters — Does it work??

https://www.youtube.com/watch?v=nz1t6QtARyI

WD-40, which has paraffin wax as an ingredient, can be brushed onto the crinkle finish of a typewriter to clean it up and give it some shine. Use a rag to wipe off excess and take care not to get any in the segment comb. The difference on a generally clean typewriter appears to be negligible and primarily results in a WD-40 smell.

Would something like Armor All work better? Car wax might also work as well. Powder coating polish could work, but it may act as a gentle abrasive as it is also meant to lift stains.

How to Clean a Typewriter

Rubbing alcohol or WD-40 for cleaning out light rust, oil, dirt and grime.

Use Rem-Oil for oiling typewriters

Toothpaste and toothbrush is great for cleaning crinkle paint on typewriters.