The top and bottom bearings were lubricated with light motor oil, which is able to handle the relatively high temperature that this sort of motor runs at.
On the second attempt I had a neatly assembled and balanced rotor. The magnet snapped off, so that had to be cleaned up and glued back on as well. If only it was that easy! First attempt I missed, so I had to remove the disc again with brute force. I marked the outside of the parts with a sharp scribe, as can be just seen in this picture, so I could superglue them back together in alignment. Care is needed to get the ring back in the correct orientation to ensure balance is restored. The clue here was observance of the pattern left by the broken glue and using this to establish the correct position. The fix was to dis assemble the rotor, clean it up and put it all back together. This having come adrift explains why the thing is running rather rough. Much like the wheels of a car are balanced when you have the tyres changed. During manufacture holes are drilled in this and the base ring of the rotor so that it runs without shaking. It’s main purpose is to provide a means of balancing the motor mechanically. This magnet is the “synchronous” part of the motor. However, above that on the shaft is a grey disk. On the left we see the usual squirrel cage rotor associated with induction motors. They also accommodate 110V by connecting in parallel or 220V if in series. The dual coils make for a 4 pole rather than 2 pole motor for smoother running. Looking at the stator we see a pretty standard shaded pole induction motor. I’ve never seen a motor that claims to do both. From my university studies of Electrical Engineering I know how induction motors work, and I know how synchronous motors work. Just 2 bolts held the whole motor together. It’s held in place by just 3 cir-clips and connected by three wires. Not a great look for a precision record player. After the accident the motor wobbled, made a horrible scraping noise and ran slow and hot. Plenty of torque available to turn the rather hefty 2.3 Kg platter of the Garrard Zero 100SB turntable from which it came. Prior to the accident this motor ran beautifully. Weighing in at 3/4 of a kilo it fell hard. Hopefully I can fix it.
Garrard Synchro-lab motorĪn unfortunate moment of butter fingers led to the demise of this one when I dropped the turntable it was inside. I apologize for how dumb this seems, but it has worked for me.By combining induction techniques for torque and synchronous operation for speed precision, Garrard produced a motor which was revolutionary for its time. You just need it to go completely through the cycle on it's own, even slowly. (I usually go in 1/2 hour increments.) When you go back to the 33 speed, it will start to work. If it doesn't make it through the cycle with the weight, use the 45 rpm speed for a while. If it makes it through the cycle, (even slowly), I let it run until it starts to cycle much smoother. I have the tonearm cued in the up position to not damage anything. I'll wrap a rubber band around the cycle switch and hang something off of the other end so it retriggers the cycle function on it's own. I've placed 4-5 records for weight on the platter so they'll be more inertia to help keep the cycle going. Now, if it still does that after cleaning, (which DOES happen).Here's a slightly jerry-rigged way that has worked for me in the past. This is always the last thing to take care of after you get it back together. I've done about 20 Garrards, including 3 Zero 100's.
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