To finalize the mechanical repairs on this Beogram 4002 (5503) turntable, new transport lock bushings were necessary. These bushings ensure the sub-chassis is properly aligned within the upper and lower lock positions. This particular Beogram was missing these bushings, with no indication they were ever there. This photo shows the left transport lock disassembled:

The bushing should be located in the opening on the sub-chassis arm on the right.

The first step of the replacement bushing installation is shown here:

The replacement bushings were designed in two parts to simplify installation, eliminating the need to remove the sub-chassis. A video demonstrating the installation of the transport lock bushings is available in the Beogram 4002 playlist. The bushings can be purchased from the Shapeways store. Two bushings are required per transport lock.

Here, the upper half of the bushing is shown installed:

This shows the reassembled lock with the new bushing. This process was repeated for the remaining two locks. Taking advantage of the opportunity, the original, cracked cabinet guiding washers were also replaced. The replacements, now printed in nylon using selective laser sintering, are more precise and offer greater mechanical stability compared to the initial stereolithography reproductions. An example of a cracked original washer is shown here:

The cracked washer is pictured alongside its replacement:

And, finally, installed:

A video demonstrating this procedure is available in the Beogram 4002 playlist. The washers can be ordered directly from the Shapeways store. With these replacements complete, the sub-chassis and platter height are ready to be adjusted.