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Pictured above is the last design loading assembly. It is motor driven and shares some issues with earlier types. The most common problem is the driven pins on each side get brittle over time and shear off. These are attached to the cassette carriage and a lever arm the moves the receiver in the guide slots located in the side plates on either side. As the driving arm (lever) moves front to back the pins slide along in the slots making the receiver travel backward and down to load the cassette. The process is reversed during unloading. When the pins shear off cassette becomes cocked on insertion. It can become trapped and damage to the machine and tape can result. Click on the picture. Pictured here is the cassette receiver removed in the upper left and two broken off pins laying on the transmission cover. When the pins break off the driving arm can no longer move that side of the receiver. Click on the picture. Here are the pins and receiver in close up. Click on the picture. Here is what remains of the pins after they break off. The loader assembly is no longer available so the only solution is to replace the pins. Click on the picture. The first thing to do is to remove the stump. Here you see the plastic being machined away around the metal center upright. Click on the picture. Here is a picture showing the area after the plastic has been removed. T he metal upright can be seen in the center. Click on the picture. This photo shows the replacement pins that will be bonded to the metal pin. They are made of polystyrene and have to just the right length and diameter. Notice they have holes through the center. They will be pressed over the metal pins. Click on the picture. Here we see that the replacement pin is in position and phenolic resin has been added around the opening for re-enforcement. The resin is a special fine powder that hardens when a liquid agent is added. It binds with the pins and the plastic receiver material together for strength. Click on the picture. This shows both sides of the receiver after a repair and hardening. Click on the picture. Here is on side after clean up. It is very important that the pins be uniform and of the right diameter otherwise the loader will hang up and not travel smoothly. Click on the picture. This close up shows the pin in place in the loader lever arm and ready to operate the cassette tray. This completes this repair. Click on the picture. Here is the repaired loader with a cassette inserted ready to operate. It is even with the front and not cocked or crocked. Another failure for this type loader is the left side lever (driving) arm falling off. As you can see from the above composite photo there is a slot in the arm that is curved and a clasp that is supposed to hold the gear in place. Unfortunately sometimes this plastic clasp gets bent or deforms with age and allows the lever arm to slide outward and coming loose. Click on the picture. There is a simple and effective way to correct this failure and prevent it from happening again. The center shaft that the arm rotates on has a small hole in it and inserting the proper type of screw and washer on the shaft corrects the problem. Click on the picture. To simplify production Sony designed later model loading assemblies with a snap on driving arm. Held in place by a plastic clasp that captured the arm in a slot, it would sometimes pop off causing the loader to fail. Then when a cassette was inserted only the right side arm could move the carriage, pulling it off center and driving it inside at an angle. If you were lucky the loader would reverse and force the tape back out, but in a lot of instances it would become trapped. Once cocked in the machine, repeated cyclical attempts by the system control circuits eventually resulted in damage to the power supply. The repair solution is to place a screw in the center shaft that the lever arm rotates upon. A washer is used under the screw for proper clearance. Click on the photo to see the repair. Click again to a Sony production change that corrected this problem. There is another more complicated loader repair that I perform just for the SLO-1800. To see it click here. To proceed to the next section that describes the EXTERNAL CLEANING AND RENEW click here.
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