It can be useful to take some mineral spirits, naphtha, or paint thinner and a tooth brush (or, even better, a brass bristle brush) to your typeface every now and then to clean the ink, dirt, paper, bits of ribbon, dust, etc. out of it. Doing it after changing ribbon is always a good idea. If you're really hard pressed, nail polish remover (acetone) or rubbing alcohol and a cotton ball along with a small pin tip for the loops of letters like 'a', 'o', 'p', 'g', etc. can be used.

How well (or not) your typewriter works from a print perspective can also change with the type of paper you're using, what your ribbon is made out of (usually nylon, silk, or cotton), how much ink it's got in it and how old/worn it may be. A good backing sheet behind your typing paper can also be helpful.

reply to u/kirrachristine at https://www.reddit.com/r/typewriters/comments/1dtuksy/one_letter_weirdly_thicksmudged/ RE: one letter weirdly thick/smudged

Smith-Corona 5-Series Touch Adjustment by [[Joe Van Cleave]]

https://www.youtube.com/playlist?list=PLJtHauPh529XYHI5QNj5w9PUdi89pOXsS

Typewriter 101

https://tsesaraheverett3.wixsite.com/justmytypewriter/team-4

To be more specific on solvents for beginners, potentially try mineral spirits (white spirit in UK), paint thinner, naphtha (lighter fluid), kerosene, varnish remover, PB B'laster, or carburetor or brake cleaner. Be careful as many of these are flammable and some can remove paint or decals; use all of them in a well ventilated area. You may see some recommend household variations of alcohol, but these do contain water and generally aren't very effective solvents for the types of oil/grease/dust you'll probably want to remove; professional typewriter repair shops would not use alcohol on a machine. And for those in the back, no one but a psychopath would use WD-40 on a machine's internals.

https://www.youtube.com/watch?v=xjumGF9NFE8 is a pretty solid cleaning primer. Searching YouTube will uncover some potential additional advice in addition to what you can find at https://site.xavier.edu/polt/typewriters/tw-restoration.html

Good luck. That's a lovely machine!

https://www.reddit.com/r/typewriters/comments/21zpri/what_you_should_know_before_cleaning_your/

Note the stated 33 year experience as typewriter repairman

should find a better reference

Typewriter 101: THE CLEANING GUIDE! by [[Just My Typewriter]]

A solid primer for cleaning typewriters

The white gunky substances seen on the plastic keys of old, unmaintained typewriters generally isn't mold, but plasticizers coming out of the plastic. These can usually be cleaned off using simple household cleaning products or if necessary heavier cleaners (Goo Gone, alcohol, naptha, etc. - test these on hidden parts first to ensure they don't react with or destroy the plastic or remove the paint of the key letters) followed up by light waxes or polishes and buffing.

Wiping dirty plastic typewriter keys with a soft cloth and then waxing/buffing them can bring them back to life.

Cleans them but probably doesn't repair them.

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.

Hermes Rocket Typewriter Case Cleaning — Crazy Results, Simple Tools

A few hours with some mild soap and water and a toothbrush will clean up most of a plastic typewriter case.

A mild solvent like isopropyl alcohol can generally get the remainder of any tough spots or gummy spills.

DIY Restoring Yellowed Plastic Featuring Royal Mercury Typewriter

Yellowed plastics can be treated with sunshine (or other UV light for several days) and hydrogen peroxide (3%) to repair the yellowing.

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.

Typewriter Cleaning and Repair Basics #2 Type Bars, Case, and Crinkle Finish

https://www.youtube.com/watch?v=82O_iUAI5og

Segment comb cleaning - isopropyl alcohol (gentler solvent) - odorless mineral spirits - Lacquer thinner (maybe a bit too aggressive) - naphtha (lighter fluid) take care for flammability and ventilation

Work solvent into bearing between type bar and segment comb. To dry things out one can used compressed air when done or just air dry.

If sticking keys not due to being gummed up, bend portions slightly for better alighment.

Do not lubricate the segment comb.

Only lubricate the carriage rails when necessary.

Exterior cleaning

Brass bristle or nylon bristle brushes (toothbrushes) can be used to clean the exterior of the typewriter and/or cases with mild detergents or other solvents. Depending on the finish, try the brush and solvent on a small portion to determine colorfastness and potential scratching first.

Typewriter Cleaning and Repair Basics #1 Assessment and Testing

Recommends against any lubrication on the key mechanism, just keep it clean. Lubrication in some cases may actually gum up the works and cause the keys to return slowly.

He suggests Krud Kutter as a cleaner/degreaser.

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.