Richard Polt has collected a number of typewriter manuals from various sources, including this site. After an email discussion we decided it would be a good thing to duplicate these manuals just in case something goes wrong online.
The Ames Corporation used to make various typewriter parts including rubber parts. Until just a few years ago, the company continued to recover platens and other rubber parts. Unfortunately, they no longer provide that service. While in the typewriter business, they produced an extensive manual for typewriter repair and adjustment. Here’s a scan of one of the manuals.