Tip: of the 3 things WD-40 is actually useful for on a typewriter, one is cleaning and giving a nice sheen to crinkle paint safely. Apply lightly on a clean rag. The other two are cleaning white-out off plastic card guide without fogging the plastic, and removing the calcified masking tape often found on SCM portables.
via Ted Munk as a comment on a YouTube video
Typewriter Clear Plastic Card Guide Holder Clean Polish White Out Dirt Restore by [[Phoenix Typewriter]]
For cleaning white out off of the clear plastic on card guides try the following: - scrape with fingernail<br /> - Simple Green - Marvel Mystery Oil (from automotive shops) followed by lacquer thinner in miniscule amounts (one drop). The oil helps protect the plastic from melting from the lacquer thinner. Rinse and repeat.
Others have indicated that floor wax stripper will remove white out without damaging the plastic of the card guides.
When the card guidesare also used for classification purposes (144) a specially strongguide should be selected, as their replacing entails a great dealof re-writing.