J.A. Michell Prisma restoration

Pulled the motor apart this morning. The motor itself is sealed too. Got a broken wire, and at least one of the speed pots didn’t have the spindle engaged properly to the wiper. Seemed to work but may not have been travelling full sweep. Now I gotta figure how to get some oil into this motor... might have to drill an oil hole in the bottom bearing cap.
 

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Well fudge... looks like a hidden speed trim pot on the motor itself. There’s a tiny access hole in the cover lets you reach it...
 

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I am tempted to drill those four brass eyelets out and pull the motor housing apart...
 
You"ve gone this far...
Looks like the only way to proceed... damn these wires are FINE... they’re going to be a bugger to strip and solder. Even with my glasses I can hardly see them.
 
Soldering in the kitchen, she’s not even phased anymore :cool:
 

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Got called away to a friends place cuz his shop was flooding. Move some snow should help
 

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Drilled rivets, white knuckle for a bit... man this stuff is delicate... motor went well until I was putting the speed trim pots back together... snagged one of the wiper discs and launched the brush... F$&@ING F&$K! Spent about an hour and whittled a new brush from a pencil lead. Adjusted the hidden trim pot and was able to dial the strobe right in. The repaired pot was the fine adjustment, works fine. Installed the SAS stylus, damn it’s almost invisible it’s so tiny. Did a quick alignment/VTA adjustment, things are close now. Made new felt pads for the platter weights where the record sits.

Officially working now, rest is cosmetic details and a final set up. Even got some horse hair coming for new sweep brush.
 

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Stops and prop rod installed. Now I can ditch the block of wood holding the lid!

What a difference in tone and quality even through these questionable speakers when compared to using an iPhone as a source. Not surprised it’s better, but damn IT’S UNBELIEVABLE!
 

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The skills of a surgeon, a little mechanical know added in, all necessary faculties needed for vintage goodies.
 
The skills of a surgeon, a little mechanical know added in, all necessary faculties needed for vintage goodies.
Thanks W-r... I wasn’t sure the patient was going to pull though for a little there... I was VERY nervous splitting he motor then when I saw the rotor either side of the windings I though for sure I would have destroyed them.
 
A big pat yourself on the back you lucky guy to own such a nice toy and to make it work is even better! I't a beauty.
 
Thanks guys. Just got back from around he corner and Saturday nights obligatory speaker lubrication session with friends. Tossed an album on before bed.


Lee, now that this is (almost) done and Linda hasn’t gone up in flames yet, I promise I’ll get back to the other thread and check her bias before I push her any harder!
 
That's a very unique table Andrew, and beautiful too...
I’m very fortunate as I would likely never have one like it if the circumstances hadn’t aligned. My uncle bought it new and when she was tired he passed it on to me. I’m just glad I can tell him she lives again. I’m almost ashamed to say, the single largest one transaction outlay of maple syrups ($$$), was the stylus, so I’m not Really all that deep into her.
 
I don’t know if a photo can capture this, but I just found this... I knew it was in the shipment from my dad and he said to “keep an eye out” for it. It has only been played once since new as he recorded it to the RT-707 and played the shit out of the tape... it’s fucking immaculate. This may be the second time it’s been out of the sleeve. Sounds like it!
 

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