Discovered broken mainspring during the Tab and Carrier Return cord work

FOUND ANOTHER METHOD ONLINE AND TRIED IT

The key to this new method is that I don't have to shorten the tab cord with a knot. That dramatically reduces the risk of the cord popping off the pulley as it did before. This method comes from a Phoenix Typewriter YouTube video I just watched.

First step, with all cords disconnected from drums, is to latch in carrier return and hand cycle until the mainspring stops at full tightness. The next step would be to release about seven turns before attaching cords and the rest. 

The mainspring never tightened past a certain point, which indicated that it was broken internally. That explains some of the funky behavior I saw during my prior attempts to attach the cords 

DONOR SELETRIC TO THE RESCUE, AGAIN

The mainspring on the Selectric 1 I bought as a parts donor was in good shape, so I moved it over. I then opened the original mainspring and confirmed that it had broken inside. 

Broken spring

Donor machine replacement

Next session in the workshop I will wind it up then go through the Phoenix Typewriter procedure to try to get my carrier return and tab cords properly installed. Hopefully that will be successful so that I can move on to fixing the excessive tension on the Rotate spring.