Cleaning up the stacker mechanism

REMOVING CRUD AND CORROSION ON PARTS

Most of the brown caked crud on the parts, which looks like rust, is actually a mix of mouse urine, dirt and a bit of aluminum or other metal corrosion rather than iron oxide. I was able to remove much of it with 409 spray and in some cases a mild sanding block to break free the layers. 

Example of corrosion

The rod that the card stacker shoe slides along cleaned up quite nicely. With a bit more work on it and some cleaning of the side plates that the shoe slides underneath, I should get it to return rightward under spring tension and move freely. 

MORE DISASSEMBLY IN ORDER TO CLEAN AND LUBRICATE CARD PUSHER PARTS

I removed the metal arch that converts the card motion from horizontal to vertical as it enters the stacker. This gave me good access to the card pusher plates that should oscillate smoothly left and right to move cards leftward to join the stack of other cards. 

I did a trial assembly after the cleanup and lubrication and found that everything moved reasonably well, but still had some resistance that kept the return spring from always pulling the card pusher plates rightward. The cam which causes the pusher plates to oscillate will move the plates leftward at its high spot but when the cam profile lowers, the spring must move the plates rightward to ensure smooth back and forth action. 

Pivot driven by cam moves card pusher back and forth

Shoe at bottom sliding on the rod

WORKING ON EASY MOTION WITHOUT ADDING OIL

Normally with mechanical parts I would add some oil or grease to reduce friction and ensure smooth motion. However, the stacker parts can come in contact with the punched cards. Since they are made from paper they will wick up some of the oil. 

That would cause the card to swell up. The throat in a card reader that allows just one card to enter at a time is based on the nominal thickness; a card that is too thick will jam up and bend. 

Therefore I have to find a way to reduce friction without the oils. I will use a combination of paste wax and more work removing sludge and corrosion from the moving surfaces. 

DISINTEGRATED BUMPER THAT MUST BE REPLACED

Below you can see the broken fragments of the bumper that the cards will fly up into and come to a stop. Fortunately I was warned about this and already have a replacement part in the works. 

The sound deadening foam that was glued between the ribs above has disintegrated. This is pretty typical of the foam used in 1960s IBM gear. I will remove it since it has no functional role, simply reduces sound levels. 

DISCOVERED MY ISSUE WITH HOPPER GEAR ALIGNMENT DOESN'T EXIST

In prior posts I was concerned about the timing between the picker knife actuation cam and the timing disk. The solenoid for the knife is triggered at the time of the CB 3 pulse from the timing disk and released at CB 1 time. This timing also starts the card feeding from the pre-read station out through the read photocells and into the stacker. 

I was worried that if the knife moves at the wrong time when the previous card hasn't cleared the pre-read station, we could have a jam. I wanted to get a copy of the FE Maintenance Manual to learn how to mesh the gears for proper synchronization.

However, that was due to a big misconception of mine. It appeared that the gear with the timing disk on it was meshed to other gears that not only turns rollers to move cards but also turns a cam to move the picker knife. Thus, the two gears would have to be set in the proper relationship in order to turn the cam at the right time. 

The diagrams in the Parts Catalog appeared to match that assumption. However, as I disassembled the card reader I realized that the cam for the picker knife is on the SAME shaft as the timing disk. The shaft has a key that orients the timing disk to the shaft, thus the timing between feed and pickerknife are assured. 

DRILLED OUT AND REPLACED A FROZEN RUSTED SCREW

As I was removing side plates to get access to the card stacker shoe and rod, one of the screws was too rusted in place to turn with a screwdriver. It was a recessed head screw as well, thus harder to apply turning torque to the end of the slot. I had to drill out the head in order to get the screw turning. 

Fortunately, it was a pretty standard type of screw that I could buy and use as a replacement when I reassembled the stacker assembly.