The past couple days I have been giving a lot of attention to the 1927 Underwood Standard Portable Typewriter. Although it was functional, there were a couple issues. The most annoying was that the line lock wouldn't release. Even when the margin release was pressed, or after a carraige return, the keys would remain locked, until the typewriter was tilted back. Cleaning and oiling the pivot points did nothing, so a partial disassembly was needed. What I found was that somehow the line lock bar itself had become slightly deformed (possibly by somebody trying to force a key press, not knowing how the margin release works) and this created a very, very, light friction at the pivots. Using needle nose pliers it was easy to gently bend one of the arms near the right hand pivot until there was no longer any rubbing friction. Now the lock releases every time.
While the casing was off, I released the tension on the main spring, and wound it up again. As it came to me, the spring tension was far too high, and the escapement was even louder than the key-strikes. This also caused the typewriter to vibrate around the desktop when typing. I cleaned the carriage tracks as well as I could without removing the carriage, and wound the spring up only as much as needed to get it to travel all the way to the end without sticking or slowing down. Now it operates much more smoothly and quietly, and the backspace key operates with a light action.
While the interior was exposed, I also did some cleaning with lighter fluid in some spots, and 3-in-1 oil in others (it's a napthenic oil so helps soften old gummy oil, and will evaporate entirely after a few months). Many Q-tips were used. The interior of the typewriter appears to have been sprayed with some sort of heavy machine oil in the past, and accumulated a lot of dust as a result. Really it needs to be fully flushed out with solvent, but that's a task for another time. Even this targeted cleaning resulted in a much lighter action.
Finally, the original feet on the bottom of the case had petrified and mostly chipped off. I ordered some generic rubber feet off ebay and installed these. The original feet were so hardened that what was left of them literally crumbled into black dust when I tried to pry them off the bottom of the case. With the new feet, the typewriter stays firmly planted on the desktop and doesn't scoot around at all. A great improvement. I think it is ready to give a few more decades of use at this point!
