The photos from "leforum" are the best illustration of what I saw when I took my 7045 apart. Note the brass-colored rod that ends in a "nailhead" shaped flange. That nailhead would not dissociate itself from its hole in the pillar, which is needed to enable one to slip a new washer into place. (I fully agree that a replacment washer or O-ring is easy to find.) Perhaps I gave up to soon. I did twist and turn the two parts at different angles to each other, but the nailhead shape would not disengage. Since I have no immediate use for the UA7045, I gave up temporarily.
Victor UA-7082 Arm, Rubber Washer at Rear Counterweight Tube: Sag/Repair/Fitting Damage.
Victor UA-7082 Arm, Rubber Washer at Rear Counterweight Tube: Sag/Repair/Fitting Damage.
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The Large Plinth with UA-7082 I bought arrived, the plinth, legs, dust cover seriously damaged. Insured, at UPS for damage claim now.
The arm, before I bought it, the counter weight tube was sagging (very typical it seems), because the rubber washer between the main tube and the rear counterweight tube had deteriorated (the typical age related problem).
I pointed it out to seller, he fixed it, posted new photos, I bought it.
The arm arrived undamaged, however, it was going back, and, perhaps I will buy one in the future with bad rubber, soooo, I decided to see how he fixed it.
I’m no engineer, this is my attempt to clarify the rubber repair for myself and others. Lot of words to attempt clarity, it’s not that complicated.
1. the 7082 (presumably 7045) rear tube and counterweight are not totally isolated from the arm by a tubular layer of rubber like my SME 3009 was. (I repaired 3009 with factory rubber tube from SME when I first got it).
2. The 7082 rear tube is threaded, It threads into the back of a fitting on the end of the main arm, just behind the pivot. Not tight machine threads, so minor movement can occur. That is a semi-solid, not totally isolated connection. If the rubber washer is weak, these loose threads allow sag to occur. Perhaps the threaded shaft gets bent down also.
3. You thread/snug that rear tube forward against the rubber washer. The thickness of the washer is therefore not critical (except too thin). The density of the rubber needs to be firm enough to keep the rear tube from sagging, but not too hard, so it can do it’s job: dampening vibrations traveling down/back up the tube, isolating counterweight .... engineers can clarify this design function.
4. Washer Shape. Factory ____? This one: It did not slip off the front tube as I expected a simple washer would. It had an integral smaller diameter ’shoulder’ or ’neck’ that projected forward into the rear tube fitting. There are two tiny allen-head set screws at the bottom of the fitting. I loosened them and a short piece of tube came out, less than an inch long, rubber washer at the rear end.
5. Front face of the small fitting with the washer has/had a brass faced plate, curved. This one was damaged, part missing, part ’mangled’. My guess, it was set too tightly to the face of the arm shaft, someone messed with it, who knows ....
6. The point is, unless I took it apart, it looked fixed, you would definitely choose this over one with deteriorated rubber, sagging rear tube. But it had invisible damage. No way to know if buying used. Or know after you received it. I think this is probably a very rare instance, just mentioning it, perhaps someone knows something about it _____ ?
7. Effect performance??? Many have said they have weak rubber washers/sagging rear tubes: so what, plays great. The fitting: internal damaged brass face could be carefully reassembled, making sure no contact with anything.
8. Anti-Skate. I don’t like it, especially used. The plastic cap lifted off to reveal a spring coiled around the shaft (cap’s tiny set screws too loose?). Turning the top dial compresses the spring, step-less progressive resistance to the rotation of the arm shaft, great ... Counter-acts inward force when playing.
Perhaps I would be confident with new from factory, but, there is no way I would be confident with this one, or any used one. Where is zero? Prior in-appropriate revolutions? Weakened spring?
I like dangling string counterweight with many small 1/4 gram notches like the SME and others. One thing I did not like about my 3009 Anti-Skate was the age and brittleness of the plastic line, but it always tested accurate in use.
9. Actual anti-skate. Listening, test record, final set of anti-skate is best. But, when changing cartridges, Stereo to Mono, Shibata to Elliptical: quickly adding or reducing tracking force, then a quick anti-skate corresponding change ..... no listening test, trust the incremental changes from prior proven setting. I feel more confident moving the string to the next notch than adjusting a spring.
Hope this is helpful, perhaps others can clarify anything I got wrong.
Elliott
................
The Large Plinth with UA-7082 I bought arrived, the plinth, legs, dust cover seriously damaged. Insured, at UPS for damage claim now.
The arm, before I bought it, the counter weight tube was sagging (very typical it seems), because the rubber washer between the main tube and the rear counterweight tube had deteriorated (the typical age related problem).
I pointed it out to seller, he fixed it, posted new photos, I bought it.
The arm arrived undamaged, however, it was going back, and, perhaps I will buy one in the future with bad rubber, soooo, I decided to see how he fixed it.
I’m no engineer, this is my attempt to clarify the rubber repair for myself and others. Lot of words to attempt clarity, it’s not that complicated.
1. the 7082 (presumably 7045) rear tube and counterweight are not totally isolated from the arm by a tubular layer of rubber like my SME 3009 was. (I repaired 3009 with factory rubber tube from SME when I first got it).
2. The 7082 rear tube is threaded, It threads into the back of a fitting on the end of the main arm, just behind the pivot. Not tight machine threads, so minor movement can occur. That is a semi-solid, not totally isolated connection. If the rubber washer is weak, these loose threads allow sag to occur. Perhaps the threaded shaft gets bent down also.
3. You thread/snug that rear tube forward against the rubber washer. The thickness of the washer is therefore not critical (except too thin). The density of the rubber needs to be firm enough to keep the rear tube from sagging, but not too hard, so it can do it’s job: dampening vibrations traveling down/back up the tube, isolating counterweight .... engineers can clarify this design function.
4. Washer Shape. Factory ____? This one: It did not slip off the front tube as I expected a simple washer would. It had an integral smaller diameter ’shoulder’ or ’neck’ that projected forward into the rear tube fitting. There are two tiny allen-head set screws at the bottom of the fitting. I loosened them and a short piece of tube came out, less than an inch long, rubber washer at the rear end.
5. Front face of the small fitting with the washer has/had a brass faced plate, curved. This one was damaged, part missing, part ’mangled’. My guess, it was set too tightly to the face of the arm shaft, someone messed with it, who knows ....
6. The point is, unless I took it apart, it looked fixed, you would definitely choose this over one with deteriorated rubber, sagging rear tube. But it had invisible damage. No way to know if buying used. Or know after you received it. I think this is probably a very rare instance, just mentioning it, perhaps someone knows something about it _____ ?
7. Effect performance??? Many have said they have weak rubber washers/sagging rear tubes: so what, plays great. The fitting: internal damaged brass face could be carefully reassembled, making sure no contact with anything.
8. Anti-Skate. I don’t like it, especially used. The plastic cap lifted off to reveal a spring coiled around the shaft (cap’s tiny set screws too loose?). Turning the top dial compresses the spring, step-less progressive resistance to the rotation of the arm shaft, great ... Counter-acts inward force when playing.
Perhaps I would be confident with new from factory, but, there is no way I would be confident with this one, or any used one. Where is zero? Prior in-appropriate revolutions? Weakened spring?
I like dangling string counterweight with many small 1/4 gram notches like the SME and others. One thing I did not like about my 3009 Anti-Skate was the age and brittleness of the plastic line, but it always tested accurate in use.
9. Actual anti-skate. Listening, test record, final set of anti-skate is best. But, when changing cartridges, Stereo to Mono, Shibata to Elliptical: quickly adding or reducing tracking force, then a quick anti-skate corresponding change ..... no listening test, trust the incremental changes from prior proven setting. I feel more confident moving the string to the next notch than adjusting a spring.
Hope this is helpful, perhaps others can clarify anything I got wrong.
Elliott
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- 33 posts total
look at the photo where the brass piece is completely separate, no old rubber on it. right of it, short chrome piece with notches to receive/retain the flange, and keep the brass piece from rotating after assembled. the flange stays on. push the threaded end of the brass thru the short chrome piece. the flange and notches now mated. put the short chrome piece into thew hole in the back of the pivot. verify no physical contact when arm is moved in all directions. tighten set screw fixing short chrome piece. slide the two layer grommet past the threads onto the brass piece, the smaller forward layer pressed into the short chrome piece, now invisible. the second layer of the grommet is against the rear of the short chrome piece, visible, the part of the grommet that is always visible. spin the entire rear counterweight assembly (it has internal threads) onto the threaded shaft of the brass piece. rotate the assembly forward until it is snug to the rubber grommet. tighten set screw. assembly complete, entire rear assembly totally isolated from the front by the rubber grommet. now, the balance and stylus force can be made using the movable weight collars. |
Many more modern tonearms also use some method or other to decouple the counter-weight from the pivot. Even if, for example, the Victor arms had used a super quality rubber, they would have yielded by corroding slowly and inexorably, causing the counterweight to descend as if it were a defect; the counterweight is heavy and deforms the rubber on which you have to resign. For me the best solution is the one adopted by Denon for the DA307 arm which uses a solution other than Victor, that is, it isolates the barrel from vibrations and counterweight. The barrel is lighter than the counterweight and the cantilever / dumping unit will horizontally support the barrel without problems and without ever deforming and destroying the rubber. Furthermore, the rubber of the Denon DA 307 is conical and adheres well to the structure without slipping and is of the highest quality; even after 40 years, completely disassembling the arm for overhaul and maintenance, it shows no signs of wear or cracking; the rubber appears new and elastic indicating how I wrote a truly exceptional rubber. |
best-groove409 posts01-11-2020 4:59pmI repaired and replaced the Victor arm rubber a short time ago, no problem if you are practical with DIY https://i.postimg.cc/JhGB0fL8/DSCN5962-thumb-jpg-da81b9ff50d69a0d02549b0dc19fd7f4.jpg ..................................... Not to be critical, however, to clarify for others, in the photo, the center piece is show reversed. The small diameter threaded shaft is shown forward, it should face rearward. That rear facing threaded shaft is what the entire counterweight assembly threads onto (counterweight assembly has internal threads). You spin the counterweight assembly forward till it is snug against the rubber grommet, and fasten a set screw. Then, balance and stylus force are achieved. |
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- 33 posts total