Disassembly and inspection
Low serial number. #2729
Bearing
A wear pattern is visible at upper journal region. However the shaft
diameter measures
.5500 all over. No problems of form (roundness or taper)
ball bearing fits in the c'sink to carry the vertical thrust load.
This bearing housing uses a nylon bushing. Also seen in the foreground are the
end cap, thrust plate (nylon) and gasket. The three threaded holes in the upper
flange are tapped for M5 x .8mm.
The lower nylon bushing is missing..! This bearing won't be used unless
new bushings are installed. The three threaded holes at the housing bottom are
tapped for M3 x .5mm.
Outer platter: it's warped.
To check, first remove rubber mat. Three slotted M3 x .5 machine screws hold the mat down. It's an unusually narrow slot. I had to search for a screw driver that was both narrow enough to fit the slot and with enough tensile strength not to bend while breaking loose the three screws. One of which was stubborn. With the mat removed a straight edge (machinist rule) was placed over the top surface to check for flatness. Photos above illustrate the extent of the warp.
This part will have to be repaired or replaced. I will try to press the part flat by making special forms to closely fit the inner dimensions of the platter. then apply force. More on that later.
Summary:
- Platter bearing housing needs to be re-bushed.
- Outer platter needs straightening