Rega Planar 3 Motor(original model) height adjustment?

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Hi All,

I have a 1997 Rega Planar 3 with an RB300 arm, classic plinth design(square, unlike the P3-2000), and it started vibrating. Replaced bearing oil(recommended weight gear oil) as per specifications. Finally I found that the plastic motor pulley(not detached from motor, needs no crazy glue, etc.) was riding high, and rubbing against the bottom of the glass platter.

The cartridge is a new Benz-Micro Ace (Hi output) that I just had mounted and adjusted last week(not that it makes any difference, right?)

Is there some kind of adjustment to be made for the motor, or pulley, though it's suspended by rubber bands? Any help would be appreciated here. : )
 
By the way, the two top screws at the top of the plinth by the pulley hole, are regular screwdriver blade, small screws with washers. Someone told me years ago that they are *usually* allen screws? This was bought new by me, and never had any mods, as far as I can tell.
 
You are correct in thinking the cartridge is irrelevant to your motor issue.

Don't know about the screws I'm afraid but as they are, essentially, into wood (through a plastic laminate) I would be surprised if they had a socket head as these are more commonly found on machine screws (i.e. not for wood).

The plastic pulley on the Rega motor is a bit notorious for coming loose from the motor drive shaft. In your case I suspect that, rather than just spinning, it has worked its way up the shaft a little. I suggest that (holding the motor) you push it back down the motor shaft a little - a small dab of Super-Glue may also be needed.
 
if it has started vibrating it could be mechanical or electrical.

electrical could mean the trim pots on the pcb under the deck have drifted out, or the phasing cap could be on the way out.

if it's mechanical then it could be a dry motor bearing, just drip on drip on light machine oil down the spindle into the motor body.

if not that then it could be loose against the rebated plinth surface, you can tighten it up or place some thin rubber spacers betweeen the top of the motor and the rebated plinth.

i'm not sure how these are fitted, some models use sticky pads, others use allen head bolts that go through the plinth and motor body into plastic legs.

if yours is sticky pads, then remove, clean and replace with 3M adhesive pads.

a picture would help.
 
Hi GCD!

The Rega motor upgrade kits have a piece of bond tape (double sided tape) included by which the motor is mounted to the plinth. This require removing the suspended rubber mounting flange.

Now this is where I am getting... get a few inches of good bond tape (3M and such used to mount mirrors to walls). Carefully remove the old motor mount system and stick the motor to the plinth with the double sided tape (as per Rega motor upgrade).

I manufacture a Rega based turntable and mount all my motors in this fashion. It works like a charm.

Cheers
D
 
My main concern with this table, is obtaining the proper motor height(if there is such a spec, or a measurement for spacing between the top of the pulley, and glass platter) and that the screws that are there are what came with it new.

They are small flat blade silver machine screws with washers. I loosened them, and pushed the motor down, which I'm imagining that the suspension is adjustable?) and it seems to be running okay, without hitting the platter.

The belt when set on 33-1/3, rides around 1/8th of an inch from the top of the plastic subplatter. The pully/shaft has a bit of play when you pull up on it, but both metal shaft, and plastic pulley, seems to be firmly attached to one another.


Here are some pictures of it's present state:

http://www.mediafire.com/imageview.php?quickkey=rxmezi0yemz&thumb=4

http://www.mediafire.com/imageview.php?quickkey=jmoymuzxyxt&thumb=4

http://www.mediafire.com/imageview.php?quickkey=ggxxytsymti&thumb=4

http://www.mediafire.com/imageview.php?quickkey=9wtodjzztjt&thumb=4


Any advice will be very appreciated!:)

Thanks!
 
From your pics it looks like you have the AC motor version of the P3. The later ones I believe had DC motors.

Could you let us know which it is?

FWIW, only the DC motors were stuck to the plinth becuase these were quiet enough not to need the isolation afforded by the rubber o-ring mounting.

On yours, the two screws (M3 I think) screw through the formica coating and into the alumimiun bar you can just see underneath the hole. A rubber o-ring loops around this and the motor flanges and suspends the motor underneath. Positioning of the o-ring adjusts the motor position. Its fiddly to set up but I think once you're done, its OK.

If this is the kind you have, maybe some adjustment on the o-ring might do the trick for you. I also think you should try taking off the pulley and then reseating it. It does work loose and rides up on the shaft. That probably the most likely reason for the height problem. A little bit of thread lock on the shaft will retain it in place but allow you to remove it in the future should the need arise

Fran
 
You undo the screws a little bit and pull the motor this way and that way and position it better.
Be gentle with the screws, especially if they are plastic. Make sure you have the right size screwdriver.
I wrecked two of them screws, and then I had to force a new thread thru the aluminium bit with hard drive screws, and that was good.
 
At 33rpm setting, the belt should ride just a bit above center of the subplatter wheel.

There's 2 possibilites the belt is riding higher than normal

1. The motor pulley has loosened out and sits higher on the shaft.
2. There's undue wear at the bottom of the subplatter spindle shaft at the ball bearing bottom end. I've seen this once before, suspected of starved lubrication. The subplatter and ball bearing had to be renewed. When there's wear down there, its obvious the subplatter height will sit lower and may even rub the bearing flange.
Remove the subplatter wheel, being careful not to loose the 3/16" ball bearing. Inspect the bottom of the spindle shaft and ensure there's no wear. A very tiny indent where it meets the ball bearing is normal. Anything more than that is considered worn. Re lube with 2-3 drops of SAE90 gear lube on one side of the spindle, tilt the table and reinstall the subplatter assembly carefully without turning it. It'll take some minutes for the subplatter to fully seat in.
If you can show me a clear close up picture of the bottom of the subplatter spindle, I could tell you its condition.

Hope my advice helps.
 
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