Cleanup of 1131 continues

After I removed the air filters under the two SLT logic card gates and vacuumed up the fragments of filter foam in the bottom of the machine, I opened the compartments where the cards themselves are plugged. The cards plug into a backplane and then are held in position from vibrating loose by . . . more of the foam. This is the type that turns to goo, rather than the instantly brittle type, but it was very spongy at this point.

Compartment cover opened, showing dreaded foam attached to metal cover

Spongy material on compartment cover also drying on surface

Using a shop vacuum, I removed the bulk of the bad foam from the compartment doors. I then was able to peel away the plastic backing that held the foam, pulling up the still tacky adhesive between the metal cover and the plastic. Once I glue down a replacement padding, I can put the covers back on the compartments.

One panel had some chunks that already fell off inside the card compartment

Foam chunks visible in bottom mostly blocking the air inlet below SLT cards

Similarly, the air filters that crumbled away are all removed. I have some fiberglass filter material that I can insert as a replacement filter, to keep the inlet air clean so that no particles are blown onto the SLT logic cards and other components.

Today was also an opportunity to unpack and store card decks for the main diagnostics, monitor system software, RPG, COBOL and Fortran compilers and some utilities I will need as I get this system operational. I restacked the blank card boxes and the many boxes of user contributed programs in a storage area for access later when the basic system is up.

The power leads from the machine ended in loose wire ends, which I trimmed up and hooked to a Hubbell L6-20 plug to hook my my single phase 230VAC 20A power in the garage which previously fed my woodworking machinery. Everything is ready for the work tonight where I plan to carefully check out and reform the capacitors in the 1131 power supplies. Ed Thelen will join me for this task, bringing his experience doing the same for the two restored 1401 computers and others at the CHM.

Power receptacle in garage originally used with woodworking machinery

Finally, I removed the shipping bolts on the console typewriter so that I can begin reversing or adjusting the local modifications found on my machine. The prior owner added a toggle switch, red light and buzzer but they are completely inconsistent with 1130 and S/360 parts and esthetics.