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Dual 522 - What am I getting into?

Thanks for that link about mass and compliance. I'm considering going with an Ortofon Super OM 20. It weights 2.5 grams without the weight plate. Since the 1/2" adapter is already adding a little more mass to the ULM arm, I presume that leaving the weight plate off would be more in keeping with the Ultra Low Mass design.

It looks like I would have to dismantle the motor pulley speed adjustment assembly in order to disassemble the motor, so I would have to adjust that hex nut anyway when putting it back together. Once I have the motor apart, do the bearing themselves have smaller pieces which require further disassembly, or is it just a matter of putting a few drops of oil on the point where the motor shaft contacts the bearings?

Would pulling the flywheel off allow me to clean the platter bearing before lubricating it? I'm looking at what I'll have to remove in order to lube the motor and replace the clutch pad. Dual sure loves to use c-clips, don't they? I hate getting those things on and off.

Any suggestions for how to support the chassis and protect the tonearm while I have the chassis upside down? I thought about placing it on a pillow, but even that seems like it could put enough force on the arm to damage it.
 
If I'm going to put that much work into in this, I might as well have all new rubber. I'm considering ordering new speed and drive belts from LP Gear. Does anyone know if these are indeed the proper size and thickness?
 
Okay.
To have the chassis upside-down, shim the platter so that it won't spin, first. Use cardboard or something wedged in between the platter and chassis. Not too tight. Just enough.
Then use something like a large, thick, book with a towel or something on it. Place the TT upside down, resting on the platter, and with the arm hanging off. Don't forget to lock it to the rest post first! Then you'll have full access to the undersides.

Motor and pulley removal is a bit of a pain. You have to work from the TOP to remove those stupid E-clips and drop the motor through the rubber grommets. Here's a link to a pic that shows how it all goes together: http://www.audiokarma.org/forums/attachment.php?attachmentid=34243&d=1166536822 It isn't as hard as you might think... but it IS time-consuming. Yes, everything has to come apart. Just put the parts in order on the table and draw pix if you need to.

Just remember to measure the height of the bottom of the motor pulley to the top of the motor when it's all assembled. When backing out the setscrews, undo each one equally, a bit at a time. Then you won't have a problem when you put the pulley back on.

The entire motor needs to be entirely disassembled to get oil in both bearings. The motor shaft will pull out of the bearings. They're not ball, but sleeve type. They're bronze; you'll see them; no further disassembly, really. One or two drops is all you'll need.

Ortofon recommends leaving the weight plate out for ULM arms.

You'll have to remove the platter to get at the motor anyway, so oiling the platter bearing wouldn't matter if it was on or off.

I'd look at the belts here: http://www.turntablebasics.com/belts/dual.html

Tom
 
Thanks, Tom. Knowing little details like that ahead of time make the job seem less daunting. I think I may wait until I have a new pair of belts and the clutch pad in hand before cracking this thing open. That also gives me time to dig through the archives for discussions about which oil to use.
 
Almost forgot! To get the platter off, hold the platter with one hand, and press down on the chrome ring in the center with the other. While pressing down, twist it up to 60° in either direction. When it pops up, pick up the ring, and the platter can be pulled up and off.

http://downloads.nakedresource.com/download_centre/index.php?dual/dual_522_service_de.pdf is the service manual. It's in German, but the pictures in Figures 3, 4, and 9 show the pulley assembly as well as precisely where the clutch pad go.

Good luck, sir! :thmbsp:

Tom
 
I bought a needle oiler and some 10W40 (I decided to go with Seth's recommendation) over the weekend. After stabbing my fingertip trying to get that #%@^! c-clip off, I pulled the flywheel, cleaned the old oil from the platter bearing, added new 10W40 and reinstalled everything. There's no noticeable difference from before, but at least now I know how. What keeps the oil from seeping out of the bottom of that bearing? I suppose that's why it need regular lubrication.

I received my white clutch pad from All-In-One Electronics, three business days after ordering it. It's such a tiny little thing! This weekend I hope to tackle all of the underside work. An Ortofon Super OM 20 cartridge and a new drive belt are also on their way. In the meantime, I keep studying the pictures in the service manual.
 
The service manual shows a bunch of lubrication points specifying Shell Alvania Nr. 2 lubricant. Is it okay to use 10w40 in those places?
 
From what I recall, Shell Alvania Nr. 2 is a light grease. On mine, the grease had turned brown and sticky. I wiped it off as best I could with a rag dampened with alcohol and replaced it where the clutch pad rides with very light application of new lithium grease that I had in my basement. :smoke: Everyplace else I just left it alone.

I'm sure this isn't what's recommended, but it works for me. Others here surely would be better informed as to what to use and how much, Chadd.

As to no noticeable difference from before, I noticed a big difference when I lubed my platter and motor; rumble and noise went way down. Then again, it had never been serviced in all the 25+ years I'd owned it...
 
For the stylus, any of the vendors you listed do a nice job. And I second the Ortofon suggestion, if you're in the mood to upgrade/change.
 
I was planning on using Seth's 10w40 recommendation on the under-chassis lever pivot points, based on this thread, but now I'm realizing that the 1019 is pretty much all-metal under there, while the 522 uses plastic at some of the lubrication points. Is it safe to use 10w40 motor oil on plastic parts?

The Ortofon Super OM 20 cartridge arrived in the mail today. I've downloaded the protractors from Vinyl Engine and read the instructions on how to use them. How do I go about adjusting the vertical tracking angle? It doesn't appear that this turntable allows for raising or lowering the back of the tonearm.
 
1. I adjusted my Ortofon's vertical tracking angle by mounting the cart and then looking to see if the bottom part of the stylus carrier rode level as it sat on a record. Mine looked like it was dragging its rump, so I put a few 0.006" paper shims between the mounting plate and the body of the cartridge, at the FRONT. Patience helps. If the stylus looks like it's pitching forward, then you put shims at the REAR, between the cart and the mounting plate.

When the cart drags its rear end, the sound will be muddy. When it's pitched forward too much, you'll get too much treble. There's a sweet spot when the cart is level or near-level that you'll just KNOW is right when you hear it:yes:

2. I would imagine that you could use oil on plastic parts, but I personally don't see the point. A light grease is heavier/thicker, but it will stay in place and not evaporate so quickly. This is my own thought on it; any doubts, and do what Seth says in that thread.
 
The first surgery is completed and the patient is doing well. I took the motor apart and oiled the bushings, installed the tonearm clutch pad and the new drive belt, and adjusted it so the platter spins at the proper speed when the speed control is centered. The grease on the main lever pivot was glue-like, so i cleaned and oiled it. Now the automatic functions are working perfectly. I still need to find what's causing the speed shift fork to stick. But now if I tap it with my finger, the belt consistently moves to the proper section of the drive spindle. OvenMaster, I think you were right about the flabby belt. I also raised the drive spindle up to the height specified in the service manual. I think the rubber motor mounts have sagged over the years, resulting in the spindle being a little low before I adjusted it.

Next weekend I'll install the new cartridge, print out a protractor, and get it set up. If that goes well, then I'll work on polishing the scratched dust cover.
 
Uh, oh. I'm beginning to think that the platter is warped. Observing the gap between the bottom of the platter and the top of the chassis while the platter is spinning, the gap stays consistent for about 3/4 of a revolution, then it rises and falls by a millimeter or two over the remaining 1/4 of a revolution. The platter mat, record and tone arm all rise and fall at the same time.
 
Roughly one millimeter for a quarter-turn? Mine has a small (±1mm) warp every half-turn. Damn these cheap, lightweight cast aluminum platters! :gigglemad

The four or seven-pounders the older 122x series used probably don't have as much of a warp. Myself personally, I don't think it's all that big a deal, but then again, I'm no purist.

My next question is what does a perfectly or near-perfectly flat record do? Does that move up and down consistently with the platter's warp? Most of my own vinyl is so warped, it makes the platter look like precision machinery... and most likely, inaudible.

Tom
 
When I install the cartridge this weekend, I'll measure the platter's displacement with dial calipers. All of the records I've tried so far seem to rise and fall at the same time as the bottom edge of the platter. I suppose I can't expect perfection at this price point. I've spent about $275 so far for the turntable, belt, cartridge (with stylus), phono plugs, clutch pad, and shipping. Then again, I could have just picked up one of Bohhey's restored 12xx Duals and been done with it. Live and learn, I suppose. It's a good thing I like learning.
 
I installed the Super OM 20 last night and aligned it with the paper Baerwald protractor. I used Deoxit and Pro Gold on the headshell wire connectors while I was at it. The cantilever is not at all parallel to the sides of the cartridge, so I did my best to align the cantilever to the grid instead of the plastic body. Can the cartridge still perform optimally with the cantilever several degrees out of whack?

I tried playing a few tracks, and my first impression is that it sounds clearer and more detailed than the Empire did, though I still wonder what the Empire would have sounded like with a new stylus. But before I spin any more vinyl, I'm going to get some some sort of DIY record-cleaning system together. I never took care of my LPs, so they're all filthy.

I also measured the platter warp and I'd say that it's just shy of 1mm. I'm not going to sweat it at this point.
 
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