The visual appeal of a Beogram 400x relies heavily on the platter’s alignment with its surrounding aluminum panels. A correctly aligned platter sits flush with these panels, allowing the black ‘ribs’ to stand out against a flat aluminum surface. Achieving this alignment is intricate, requiring several parameters to be perfectly adjusted. I’ve observed that a sensor arm that isn’t entirely parallel to the floating chassis often complicates this process. Both the service manual and my videos detail an adjustment procedure assuming the sensor arm’s parallelism. If this isn’t the case, the process becomes skewed, leaving one or more parameters misaligned, even when the platter appears flush. This often results in a tilted chassis that rubs against the transport lock bushings.

To address this, I’ve adopted a new approach: prioritizing the sensor arm’s parallelism to the floating chassis that houses the platter. The arm sits on a carriage moving along two precision rods. These rods are secured in fixtures allowing for height adjustment with set-screws accessible from below, as depicted in this image:

Adjusting these screws typically necessitates removing the floating chassis, which is cumbersome.

Therefore, I opted for a different method. I began by detaching the floating chassis from its supporting leaf springs, letting it rest on the enclosure’s base. Next, I inserted the aluminum panels and measured the sensor arm’s parallelism to these panels at the points where the two rods are located. In this instance, there was a 1.5 mm discrepancy between the front and back rod locations. To correct this, I designed 3D-printed spacers to elevate the front rod by 1.5 mm:

This modification successfully aligned the arm:

The next stage involved aligning the platter parallel to the sensor arm, maintaining a distance of 23 mm between the arm’s top and the platter’s aluminum surface. This process essentially mirrored the procedure demonstrated in my video. Notably, with the arm accurately parallel to the chassis, the platter should already be nearly parallel to the arm when the bearing is fully tightened.

Finally, I reattached the floating chassis and fine-tuned the springs until the platter sat flush with the aluminum plates:

The result: a beautiful embodiment of Beolove!