New mainspring for typewriter, more adjustments and lubrication, motor power testing

NEW MAINSPRING ARRIVED AND WAS INSTALLED

The process of installation requires preloading the spring with about five turns while the carrier is at its rightmost position, then additional tension is added by the motor as it moves the carrier to the left in a carrier return operation. 

FREED UP LEVER SO THE CARRIER CAN SPACE

The mechanism to move the carrier one space to the right is activated in two ways - by a cam at the end of any print cycle and by triggering the operational clutch for a space. The operational clutch itself is triggered two ways - by a solenoid activated by the computer or by a pushbutton on the front of the printer faceplate which trips the trigger. 

All of these merge to a claw which pulls down on a pivot to turn the space torque bar, with the claw moving backwards and snapping off the pivot so that the torque bar is only twisted for a brief moment. This is long enough for a tooth to be pulled out of the escapement rack and the mainspring to start the carrier sliding to the right. The tooth pops back into the very next slot in the escapement rack due to the short duration of the torque bar operation, resulting in a move of just one column.

The claw was frozen in place so that it wouldn't snap off the torque bar pivot and then snap back for the next space operation. I lubricated and worked it free until it reliably spaced. 

WIRED UP MOTOR AND TESTED CARRIER MOVEMENT OPERATIONS UNDER POWER

The machine performed carrier returns and tab movements very well when commanded by the front pushbuttons. The space button triggered the movements but sometimes stuck blocking it from triggering again. I will work on that. I did a few print cycles and felt satisfied with that at a gross level. I will fine tune the selection to be sure it prints the right character during a later phase of the restoration. 

I tested the operational triggers for line feed (which worked great) and backspace, which did not work. I will have to find the gummed up parts for the backspace and ensure they more correctly. The operational clutch was turning but that wasn't translated into movement of the backspace rack. 

The shift between upper case and lower case sides of the typeball worked decently, but it needs adjustments to trip to restore to lower case. The solenoid moves a lever but the shift clutch doesn't detect that and spin. 

The typewriter is coming along very nicely and should be fully restored with just a few more hours of work.