ARXA damping question?

Discussion in 'Turntables' started by JohnMac, Feb 10, 2011.

  1. JohnMac

    JohnMac AK Subscriber Subscriber

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    Howdy all,

    I have a nice example of this table and would like to bring it up to snuff.

    When the tone arm was lowered the damping was in consistant. Sometimes it would lower properly and other times it might hover. So even when it contacted the records I couldn't be sure of the tracking force.

    I found some info on AK about dissabling the damping system but am a little confused. I removed the nylon washer and what was left of the felt washer. If the tone arm assembly is screwed too far onto the shaft the shoulder of the pin that the washers sat on makes contact with the brass part and causes resistance so I backed it off slightly.

    I read something about removing a pin but I'm not sure what that is. The pin that the washers were on goes in a slot in the brass part and seems to control horizontal play in the tone arm.

    This table came with an unopened bottle of AR lubricant so I lubed the pivot points and the shaft.

    There still seems to be some resistance when the arm is lowered. Any help?

    Thanks,

    John
     
    Last edited: Feb 10, 2011
  2. KrisM

    KrisM Addicted Member

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    8,725
    I had the same problem. That pin has to come out. Mine wouldn't, so I had to grind it off. It is probably the best thing you could do for your table. The "pin in the slot" is the one to remove.
    You have to remove the small screws(don't lose them!) on either side of the metal pivot. Carefully place the arm on it's side. When you get that apart there will be a brass barrel. The pin is inserted in that. When you put it back together you can also wrap the barrel with teflon tape to keep it rigid. Take the headshell off(be careful of stripping it!) or deploy your cartridges stylus protector. Also be careful with the thin wires that go into the table as they are easily damaged.
     
  3. JohnMac

    JohnMac AK Subscriber Subscriber

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    I could use some visual desciption. Is it the pin shown on the end of the shaft or something in the pivot assembly that isn't visable?

    If the brass barrel were wrapped in teflon wouldn't that "fix" the arm to it preventing horizontal movement?
     

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    Last edited: Feb 10, 2011
  4. KrisM

    KrisM Addicted Member

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    8,725
    If you are talking about the pin at the top of the aluminum shaft that is sticking straight up(and is screwed into the table), then no.
    From your picture, if you come from above, there will be a small screw. On the opposite side of that there is a matching screw. Just below that is a hole that the "pin" sits in. This is the pin you want to remove. If you loosen, or remove those screws, you will find the brass barrel. It will slid out of the metal piece. When you put it all back together the teflon tape on the barrel basically makes the brass barrel and this piece "one". The up and down movement of the arm is now dependent on the tightness of those two small screws. When I took mine apart I could only remove one screw. You might be able to just loosen both screws.
    I had a hard time understanding the process myself, and I'm sure my descriptions are a little confusing. And be careful with every step, those wires are thin and probably a little brittle. Good luck!
     
  5. KrisM

    KrisM Addicted Member

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    8,725
    I just re-read this part. Backing that off might help a little bit, but it really should be fairly tight now that you are removing the damping system. Part of the whole making the brass barrel, and it's holder "one". Even when new it would have been a tight fit, the barrel moved inside it's holder.
     
  6. JohnMac

    JohnMac AK Subscriber Subscriber

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    Now see the pin and how it works. With the pin removed the barrel is free to move with the holder. I'm having no luck removing the retaining screws and wonder if I could cut the pin.
     
  7. KrisM

    KrisM Addicted Member

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    8,725
    That's a tough one. Like I said I could only get one to move. I think it is worth getting it apart, I'm really happy with the pin removal and teflon mod. But I'd hate to see you damage those screws. I don't know how easy it would be to replace them.
    Maybe some sort of penetrating oil would help?
     
  8. JohnMac

    JohnMac AK Subscriber Subscriber

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    I'm going to try a little penetrating oil if I can find one of the 3 or 4 cans that I know I must have around here.
     
  9. audiojones

    audiojones Jonesin' for audio Subscriber

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    I just went through this operation a few weeks ago too and had the same problem with the arm pivot screws. On older models of the XA that I've had in the past both of the arm pivot screws would come out with no problem.

    On the newer single motor ones like the one that I've got now, only the outside screw (facing away from the platter if the arm was sitting on it's stem) was removable. The other one closest to the platter had some kind of thread locker on it and couldn't be removed.

    I think maybe AR did this to keep the arm centering adjustment correct. Maybe they realized that it's easier to adjust only one screw and locked the other one in the proper position for centering adjustment. It also makes sense because it's the outer screw that was removable, and that one is easier to get to with a screwdriver. Of course if the outer screw on yours is the one that you can't remove then my theory is shot to hell!
     
    Last edited: Feb 10, 2011
  10. JohnMac

    JohnMac AK Subscriber Subscriber

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    I can't get either one loose. I applied some penetrating oil and let it sit for a couple of hours. Still no luck. They are so tight that I think it would mess up the slots before it broke loose.

    I put it back together and it seems to track nicely but I'd sure like to do the mods.

    Hey, what carts do you guys like on this table? Mine came with an AT237E with what I suspect is a barely used stylus. It sounds quite nice. I also have a Shure V15 Type III with a NOS VN-35E stylus. I just stuck that on a Thorens to compare with the Denon DL160 that I've been using. Also have several Pickerings.
     
    Last edited: Feb 28, 2013
  11. KrisM

    KrisM Addicted Member

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    8,725
    I'm using a V15III/SAS combo and think it sounds great. I've got some other carts that I'd like to try, but swapping them with only one (touchy)headshell makes it a bit of a pain.
    I'm not sure if this is true or not, but I seem to recall somebody dipping the headshell below the platter before putting it on a record. It defeated the damping system. I'm not sure if it will work all of the time or not. I know the wonky damping system on my arm drove me nuts for awhile. I never knew if it was going to kick in or not.
     
  12. JohnMac

    JohnMac AK Subscriber Subscriber

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    Thanks for you help KrisM. Now that I understand how thing work I'll have to find a way to get thoses screws out and remove the pin. Is the pin pressed into the brass barrel. There is some access to it and I wonder if it can be worked out through the hole in the pivot body. As a last resort I could cut it off but that wouldn't help with fixing the barrel to the housing.

    Before I removed the damping washers I accidentally found that dipping the arm below the platter first helped. Now that the washers are gone and things are lubed it doesn't seem to be an issue. I was able to set the stylus force and it sets down as it should.

    I'm really liking the sound of the table. It's simplicity makes it fun to use too.

    Mine came with some cool original accessories. AR oil, AR stylus force gauge, extra used M91E cart W/O a stylus, a bunch of cart mounting hardware...and it's in superb cosmetic condition.
     

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    Last edited: Feb 10, 2011
  13. KrisM

    KrisM Addicted Member

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    8,725
    That table looks great.
    Mine came with a plastic case with two of those cartridge accessory packages, the 45 adapter(it was jammed between the sub-chassis and top plate for some reason) and an oil dispenser that was glued right next to the switch. It was broken and empty so I chipped it off.
    From what I've read the pin was pressed in. I couldn't get mine out, so that's why I used a grinder on it. You might be able to work it out.
    There's a thread that I started awhile ago on my table. As long as you skip past all of the discussions on various types of belt talc, you might find it interesting. I'm no expert on these but it is the table I grew up with, so I was(and still am) pretty keen on making run as best as possible. I got a lot of help in that thread.
     
  14. ZebraBlvd

    ZebraBlvd AK Subscriber Subscriber

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    WOW, this thread is very interesting to me. I've owned two of these tables and have never experienced this type of problem. The TA movement has been as smooth as the proverbial baby's bottom. I will learn from this thread, carry on Ladies & Gentleman. :smoke:
     
  15. macyjrm

    macyjrm AK Subscriber Subscriber

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    Unreal! I've been playing around with this same problem all afternoon. Got my first AR XA several months ago but just now getting to it. This thread is really helpful--thanks to all.
     
  16. audiojones

    audiojones Jonesin' for audio Subscriber

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    Sorry to hear that the screws are stuck so tight. Maybe the aluminum has cold-welded itself to the steel screws or something, but usually the screws back right out without a fight. So much for my theory! You really only need to get one of the screws out to remove the arm assembly, so hopefully you can get one of 'em out.

    The pin is just pressed into the brass barrel and pulls right out with pliers (at least it has on every one that I've had or done for someone else).

    I love using the Shure M91ED in my XA. I've had all kinds of other fancy expensive carts in these tables over the years but on this one I came back to the good old basic M91ED because it is a great match for this arm and it sounds fantastic. The overhang and VTA were easily adjustable to spec without having to fiddle with the installation too much and I'm so happy with the sound that I have no desire to change it.

    You are so fortunate to have that overhang gauge (the plastic thing that says "aim toward pivot"). That thing is impossible to find, and it is makes the cartridge overhang adjustment so easy. I've tried all kinds of protractors and alignment cards with parallel lines on them but with poor results. I made a copy of that gauge that you have there from vinyl engine and used it to align my cart, worked just peachy. I'd love to find the real thing some day.
     
  17. JohnMac

    JohnMac AK Subscriber Subscriber

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    It's as though both screws are welded in. I'll try another type of penetrant and try again. I messed up one screw and need to be very careful with the other. You can only put so much torque on them before the screwdriver slips.

    I think I have a couple of M91EDs but understand that good replacement stylii are hard to find. Maybe someone can point me in the right direction.

    I'm anxious to use the overhang gauge. I don't care much for the alignment card either. The force scale is kind of funky but gets you close. When I get serious about setting it up I may need a little help.
     
    Last edited: Feb 27, 2013
  18. stonedeaf

    stonedeaf Well-Known Member

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    851
    Acetone and syringe

    You can really screw this up if you aren't both careful and patient. When nothing else has worked - I've used a microdrop ( near unto none at all) of Acetone applied to screws/bolts that don't want to move - I use a diabetic syringe to apply this. Gravity has to work with you - so getting the part you're trying to break free down - so that the ol mother gravity can help you out is both vital and a good trick. Acetone will melt and or discolour a whole lot of materials - you need very ,very little acetone to do this.
    After something between 1/2 hour and 45 min. -see if you can loosen the bolt - if not - you're SOL.
    These arms came with a small foam washer on top of the shaft you're working with - just like with woofer surrounds - these rotted with time. If you see no remnants of it and the plastic/mylar/teflon ??washer that sat on top of the foam - it's been serviced or hacked at previously.
    Good luck - this is arguably the first modern turntable - sold probably a hundred of 'em back in the day - didn't necessarily age gracefully - but heck - i think all of my customer's got at least 15 to 20 years out of theirs - not bad for 63 bucks!
     
  19. JohnMac

    JohnMac AK Subscriber Subscriber

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    Thanks for the tip stonedeaf. I'm always carefull but not always as patient. I have acetone and a syringe that I use for applying small amounts of sewing machine oil to things. I'll give that a try.

    I removed the plastic washer and what was left of the foam myself so maybe no one else has been in there.
     
  20. gkimeng

    gkimeng Forum Mod, ClassicSpeakerPages.net Subscriber

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    A little late, but just in case anyone is still not sure where the pin is...
     

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