Restoring a Pioneer PL-630 Turntable

Discussion in 'DIY' started by pustelniakr, Dec 12, 2006.

  1. 50nstillhifi

    50nstillhifi Well-Known Member

    Messages:
    852
    Location:
    Carolinas
    Have a PL 510.. one of the more basic models and not as pretty... very reliable though, even today!

    Rebuilt the feet, using some materials from the local Lowes and salvaging rubbers from the original. The suspension reinstalled was not as bouncy but very stable and provided the same isolation over all.

    Just wondering, about how much did your 630 cost new? I believe the 510s ran about $120 in their prime.
     
  2. mkane

    mkane AK Subscriber Subscriber

    Messages:
    5,356
    Location:
    103 miles N. of S.F.
    630's were $275 in 78'.
     
  3. mkane

    mkane AK Subscriber Subscriber

    Messages:
    5,356
    Location:
    103 miles N. of S.F.
    Along the lines of shot rubbers and wondering if Mcmaster Carr would have a substitute. ( probably thought of long ago)
     
  4. pustelniakr

    pustelniakr Silver Miner at Large Super Mod Subscriber

    Messages:
    6,678
    Location:
    Tucson, AZ
    Most of what folks try to do with substitutes is much too tight, and restricts the suspension. I treat the rubber parts like puzzles, and use super glue to stick them all back together. Depending on broken up the boots are, this can take a while. The reassembled boots are then used as a form for the reinforcing layer of black RTV. The results are not beautiful, but the RTV'd boots work just fine.

    I am currently considering a fix, where a 2-part urethane rubber is mixed thick, and the springs are dipped in the rubber to form a new boot that won't rot. It will be a while, but I'm pretty sure that it will be do-able. I will need to work on the durometer of the rubber used, and getting it to bridge the spring coils, but I have a couple of ideas in those directions. For now, just reassemble the boot parts and reinforce with RTV. This method has worked for me for years.

    Enjoy,
    Rich P
     
  5. Binkman

    Binkman Addicted Member

    Messages:
    6,127
    Location:
    Raleigh, NC
    without all the 'dogma' or genius'.. most of this stuff is about much to do being a 'hobbyist. And I sure could use a pair of 'weather rubber over shoes' about now. :D
     
  6. jwalsh42188

    jwalsh42188 New Member

    Messages:
    2
    Hi Rich,
    I am new to this whole scene of hobby repair work on audio equipment but I am very intrigued by rebuilding a table I was gifted. I turned the table on for a few months and it was running beautifully. Then the speed issue started. In the year that the table sat with me researching how to repair it, the button for the tone arm lift began to stick. When i turn the table on the mechanism for lifing the tone arm will move if I happen to hit the button and make contact but the tone arm will not setltle onto the actual record as it did before. I have read over your thread, and began trying to diagnose the problem. I have the table apart on my work bench and was wondering if their was any insight you could give me into what those problems may be. Also, i detached the circuit board from the switch for the button, but cant figure out how to access the two small columns to observe the mechanism (maybe springs) that would allow the tonearm button to rise.

    Thanks,
    John
     
  7. jwalsh42188

    jwalsh42188 New Member

    Messages:
    2
    Also, I have a pl-610 not 630
     
  8. pustelniakr

    pustelniakr Silver Miner at Large Super Mod Subscriber

    Messages:
    6,678
    Location:
    Tucson, AZ
    First, do not use DeOxit, or any other contact cleaner around that switch. It is a snap-dome switch and will be damaged by contact cleaners.

    The actual switch (snap dome) is mounted to a small circuit board, that is held in a small case. Two screws hold the case to the control panel. The button actuator is retained by 2 c-clips. There may only be 1 spring, on one of the two guide pins. The spring force is quite light, and is there to keep the actuator at the top of its travel, if the button does not push it all the way up there. Most of the spring-back of the mechanism is provided by the snap dome of the switch.

    If the actuator is not binding anywhere, then it is likely that the snap dome switch has collapsed. If so, It will need to be replaced. Make sure the button opening in the control panel is clean, and free of damage around its inner circumference. Make sure that the guide pins are clean and not binding in their housings. Make sure the spring(s) is present. Barring any mechanical binding, the only other option is the collapsed snap dome. I do not have one of these open right now to see if a modern replacement is available for the switch itself. I will be into a PL-630 in a week or so, I can look then. Just know that you might need a parts unit for a faithful replacement. Some folks here have various PL-630/610 parts laying around. Just start your own thread, in the proper forum area, and ask if anyone has the part you need. This a good group of folks.

    Good luck,
    Rich P
     
    Last edited: Feb 5, 2016
  9. dittomusik

    dittomusik New Member

    Messages:
    33
    Location:
    virginia beach, va
    Firstly, thank you, thank you, thank you Rich P for all the info and pictures! I am working on a friend’s PL-630 and have found this thread to be invaluable.

    It had speed problems including running in reverse and runaway forward speeds. At first I tried the “pushing the 33/45 and Quartz Lock buttons hundreds of times” method, which helped some, but the problems returned very soon. So I desoldered those switches and took them apart for the proper cleaning that Rich P describes earlier in this thread.

    I took some pictures in case others who are considering doing this can see what they are getting into. As Rich says, careful handling is required, as there are some delicate little metal parts that can easily be bent (or tumble to the floor, never to be seen again) and then switch no-more-worky. Here are some details to add to Rich's info.

    This is how I did it:
    - With a small screwdriver that has a long taper (so that a flat area is on both the leverage point and retaining tab you are prying up, otherwise round shaft can slip off leverage point) and using the stand-off/larger tab as a leverage point, carefully pry up and out on the small retaining tabs that hold the phenolic plate to the body of the switch. The larger tabs will be slightly bent inward and can be bent back out (I used needle-nose pliers), just enough to be out of the way for the phenolic to lift straight up.
    - Gently remove sliding contact pieces off the stationary contacts (or out of their cavities, if any remain in the switch body) and put them somewhere safe.
    - If you tried putting Deoxit or anything else in the switch, clean it off (I used some Radio Shack no-residue contact cleaner spray - very effective on oils etc.)
    - Carefully scrub oxidation off with pencil eraser. The eraser will get pretty chewed up so be careful that the metal tube holding eraser doesn't scrape the contacts - use another eraser if it is getting close. Keep going until ALL the oxidation is gone from all sides of those contacts. Shiny. Brush eraser residue from contacts (use a non-metallic brush) and plate.
    - Position sliding contacts on stationary contacts so they are in position to drop right into their respective cavities. As Rich says, add a little Deoxit for future corrosion protection and lube.
    - Lower phenolic plate back into switch body - if it does not slide easily back into place, do not force it, the sliding contacts can get bent and ruined.
    - I used a pair of stiff needle-nose pliers to bend the retaining tabs back into place (with plier jaw on the tab and the other diagonally across the body, slightly offset to be pushing either more "down" on the tab or more "in" on the tab) , bending little by little and checking along the way that the switch could be pushed in and out freely and without restriction.
    001_IMG_4755.JPG 002_IMG_4743.JPG 003_IMG_4744.JPG 004_IMG_4746.JPG 005_IMG_4747.JPG 006_IMG_4748.JPG 007_IMG_4751.JPG
    The oxidation can clearly be seen, as can the lack of oxidation after using the eraser on the contacts.
    The speed problems seem to be gone, at least so far.

    Now there’s the problem of the speed meter, which is receiving a voltage of appx. +4v, causing it to peg hard left (I think it was left. The meter has been out of the control circuit board for several weeks now.)
    Not sure if I should start a separate thread for that or continue here ...?
     
    Last edited: Feb 5, 2016
  10. chif

    chif New Member

    Messages:
    10
    Location:
    somers, ny
    hi rich, so i finally got everything to put the tt back together.... but i seem to have hit a problem... in my zeal to clean everything i cleaned the markings off of the springs....
    anyway, i noticed that there seem to be two different types of springs. one wider coil and one tighter coil. do you know what positions they should be in?
    thanks for any help.

    chif
     
  11. pustelniakr

    pustelniakr Silver Miner at Large Super Mod Subscriber

    Messages:
    6,678
    Location:
    Tucson, AZ
    The 2 with the fewer turns per inch are made out of a slightly bigger gauge, and so are slightly stiffer. The stiffer springs are in the front left (closest to platter motor) and right rear (under tonearm mechanism), as viewed from the front of the unit.

    Enjoy,
    Rich P
     
  12. chif

    chif New Member

    Messages:
    10
    Location:
    somers, ny
    hi rich, thank you again for all your help. my 630 is all buttoned up and running great. though i have another question for you. ever since i got the tt ive noticed that the lateral level of the tonearm gimbal to be a bit off. it causes the cartridge to have a slight slant downwards towards the center. is there any way to adjust that level or pitch?
     
  13. pustelniakr

    pustelniakr Silver Miner at Large Super Mod Subscriber

    Messages:
    6,678
    Location:
    Tucson, AZ
    The gimbal bearings are not retained if you remove the bearing cone. Sometimes folks remove the bearing cones and lose a bearing. That will make a cant. Other than that, there may have been an impact to that side of the gimbal and there is damage. Parts units are required for either problem.

    Enjoy,
    Rich P
     
  14. chif

    chif New Member

    Messages:
    10
    Location:
    somers, ny
    ok so:
    1. i should source a donor gimbal i suppose?
    2. how would i disassemble the gimbal? would you know what tools are needed?
     
  15. pustelniakr

    pustelniakr Silver Miner at Large Super Mod Subscriber

    Messages:
    6,678
    Location:
    Tucson, AZ
    First, this is not a DIY operation. It requires a delicate feel that comes from experience or factory equipment. It may even be that the left side bearing cone has backed out slightly, due to a loose adjusting collar. In any case, too tight and you won't track for beans. Too loose and you will pick up a rattle during play.

    Second, I would not spend the money on a new tonearm without a solid diagnosis. Sometimes it is only a bit of play in the headshell mount, allowing the headshell to rotate back or forth a bit.

    Enjoy,
    Rich P
     
    Last edited: Apr 10, 2016
  16. chif

    chif New Member

    Messages:
    10
    Location:
    somers, ny
    Thanks again rich. Actually the playing does not seem to be affected at all. The canting is very very slight. Though if I try to jiggle the gimbal there is an ever so slight lateral movement/looseness. Again the playing seems fine and the arm tracks well. I guess I am just nitpicking the tt visually.
     
  17. pustelniakr

    pustelniakr Silver Miner at Large Super Mod Subscriber

    Messages:
    6,678
    Location:
    Tucson, AZ
    For your information and entertainment, read this whole thread through (it is short): http://audiokarma.org/forums/index.php?threads/looking-for-pl-630-610-parts.690740/

    Again, the bearing balls are not retained. If the bearing cone is removed, or loosened too much and it comes out, one or more bearing balls usually drop out with it, and jump to hidden locations. Even if you fine it (them), getting it(them) back into the bearing will be a mother bear. ONe may already be missing, by your description. By the way, the balls are the same size as those under the head plate of CT-F9XX cassette decks.

    Enjoy,
    Rich P
     
    Last edited: Apr 10, 2016
  18. chif

    chif New Member

    Messages:
    10
    Location:
    somers, ny
    so perhaps i can get such a cassette deck and use its bearing to repair my gimbal? but you did say getting the bearing back in is a major pita....
     
  19. pustelniakr

    pustelniakr Silver Miner at Large Super Mod Subscriber

    Messages:
    6,678
    Location:
    Tucson, AZ
    You do not have a definitive diagnosis yet. Diagnose... then repair. You may have an optical illusion. That would be hard to fix, indeed. And, yes, getting an errant bearing ball in there will be a serious pain.Just trying to see if one were missing would be a serious pain.Tonearm bearing issues are not recommended as DIY operations, as previously stated. The PL-630 I have on the bench right now "appears" to cant toward the center slightly...optical illusion.

    Enjoy,
    Rich P
     
  20. sl-15

    sl-15 AK Subscriber Subscriber

    Messages:
    48
    Location:
    Berkeley, CA
    Hi Rich P. Thank you for this great and thorough restoration guide! I successfully fixed my cracked tonearm pick-up plate. I manufactured a little metal band and held it in place with the set screw just like you suggested. Now everything is back together but my main problem still exists:
    When I power on the table it starts spinning immediately, no matter if it is in automatic or manual mode. When I hit the Start/Stop button the tonearm swings back endlessly. The platter never stops spinning. I looked underneath the tonearm board where the motor is and it appears it is spinning in the wrong direction. My guess is that the table "thinks" it is already running and hitting the start button is a stop function.
    Do you have any suggestions how to trouble shoot this problem? I checked the 2 micro switches at the tonearm and they work.
    Thanks for any help. Best, Stefan
    IMG_75121.jpg
     

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