TD150 motor

[matt j]

Has anyone had one of these apart successfully without wrecking it?

I have a noisy one and I'm not convinced it is entirely due to a slightly bent spindle, if you look at the two halves of the case pressings the lower half looks like it has had a whack and is out of true, so when the spindle turns the bottom of it - running in it's guide/bushing/magnet or whatever it is - catches on every revolution. I'm pretty sure I could fix it if it is possible to split it in half, but I'd rather not write it off trying.

 

[Craig B]

Has anyone had one of these apart successfully without wrecking it?

I have a noisy one and I'm not convinced it is entirely due to a slightly bent spindle, if you look at the two halves of the case pressings the lower half looks like it has had a whack and is out of true, so when the spindle turns the bottom of it - running in it's guide/bushing/magnet or whatever it is - catches on every revolution. I'm pretty sure I could fix it if it is possible to split it in half, but I'd rather not write it off trying.

You'll notice that the round flange is made up of two plates that are fastened together via the 3 rivets that the motor mounting standoffs thread into (i.e. have a look at the underside of the flange). These plates double as the magnetic field poles with each plate having 8 poles that interleave with the another to form the 16 motor poles. The metal cups are fastened to each round poles plate via tabs that are fit through slots in the plates with their ends pressed (i.e. broadened, rather than folded).

The motor housing can be split into two equal halves (i.e. upper vs. lower) via removal of the mounting standoffs and drilling out the three rivets round the mounting flange. Alternatively, the bottom cup can be pried off from its half of the round mounting flange. Personally, I'd rather drill out the rivets than risk deforming the cup, as any sleeve bearing misalignment may be made worse. The only reason to remove a cup from its corresponding poles plate is to repair or replace a phase coil, something that no one would have bothered doing back when new replacement motors were commonly available for less than the cost of the cheapest phono cartridge.

Regardless, if the lower half of the housing be sufficiently deformed such that the bearing sleeve is misaligned wrt the spindle then you'll be needing a donor bottom half assembly from a dead motor. I'd look for one on the cheap that shows OL on the upper coil but is otherwise fine. In which case, you may as well change out the spindle/pulley too.

TD-150 motor, upper half post flange rivets having been drilled out:

TD-150 motor, magnets and spindle/pulley assembly removed: