This is another modification I made to my Omni. I find the original 5-3/4″ Platen diameter to be too wide, so there isn’t enough friction between the Platen and the lap. If I turn the speed control up quickly, the lap often will skid on the Platen as it comes up to speed. This will then loosen the screw holding the lap down which makes the problem worse.
Here is the modified Platen. I had it cut down to 4-1/4″ diameter which has eliminated the skidding lap problem.
This is what the it looks like when installed in the Omni.