NOTICED ERRATIC SPACING AT TWO ENDS OF THE CARRIER TRAVEL
While I am waiting for the tool to set the initial home position of the golf ball for character selection, I did some testing of the rest of the machine. I noticed that when the carrier is near the left margin, it can fail to space. That means the escapement pawl is not pulled out of the escapement rack by the twist of the escapement torque bar.
I can see that the torque bar does bend so that it is not at a uniform distance from the carrier. There is no adjustment or way to ensure that the bar is perfectly parallel; the design of the Selectric handles this in a different way. However, there is a center support that seemed to be pushing the bar in a bow so I backed it off a bit.
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| Escapement torque bar with screw supporting it at center |
The issue occurred at the right hand side of the machine as well as near the left margin. The escapement only worked reliably in the center range. This has to be corrected.
ECCENTRIC STUD FOR ESCAPEMENT PAWL SETS DISTANCE
The design of the rear of the carrier has a bar that rides behind the escapement torque bar and a cam surface that rides in front, to keep the bar confined in a narrow range relative to the escapement pawl and rack. The stud that the escapement pawl pivots on is offset as an eccentric adjustment. One would rotate the stud and lock it into the proper position to achieve a target gap from the escapement bar at the tightest spot.
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| Top screw for escapement eccentric stud |
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| Carrier from donor typewriter |
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| Underside of donor carrier |
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| View of eccentric stud against torque bar |
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| Screwdriver reaching eccentric stud adjustment |
Once that was set properly, the space operation did not work in any location from left to right. Print escapement, the automatic spacing at the end of a print cycle, was working well. What didn't work was the operational clutch driving down a different linkage to twist the escapement torque bar. More exactly, it twisted but not sufficiently to pull the pawl out of the rack so it didn't move.
There is an adjustment to increase the movement of the link to twist the bar, which had a fairly large gap at the rest position which lessens the amount of the operational lever movement that is transferred to the torque bar. I moved the screw down to increase the range of motion, which fixed the issue completely.
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| Screw to adjust operational space movement |
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| Arm that pulls escapement torque bar |
PINSTRIPING AND KAPTON TAPE BOTH STRETCH TOO MUCH
The ribbon color mechanism used a flat plastic tape to pull or release the ribbon lift adjuster, thus moving either the top half or the bottom half of the ribbon in front of the paper. This runs around pulleys in a similar way as the tilt and rotate tapes, but is pulled by solenoids instead of mechanical linkages.
The tape was missing on the typewriter and I was working on a replacement for it. I bought two kinds of plastic tape to test their suitability for the task - automotive pinstripe tape and Kapton tape. Both were 1/8" wide and also were befouled with adhesive on one side. I thought that I could remove the adhesive if they were going to work out.
What I discovered is that both of then stretch elastically with just a moderate bit of pull. This would absorb a lot of the movement introduced by the solenoids, all of which is needed to move the lift mechanism inside the carrier.
TESTED PLASTIC GLUE FOR REPAIR OF RIGHT MARGIN INDICATOR
The right margin indicator was cracked and completely broke as I moved the margins earlier in the restoration. I wanted to test out glues to be certain it will hold the indicator together. First up, I used some plastic glue that I have used in the past when working with plexiglas and polycarbonate. The donor typewriter margin levers were my test bed. They appear to be holding but tomorrow after they have had 24 hours to fully set I will see how firmly they hold.
If that doesn't work, my
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