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Old 23rd January 2013, 06:23 PM   #11
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Well, it sounds like a very light grinding, to be honest. It's a low level hiss that sounds like metal on metal. Wasn't present when the motor was on the bench, but it's there very lightly with the belt unattached, and more so with the belt attached.

The motor took 15 seconds to spin down on the bench, and 33 seconds to spin down with the pulley attached in the deck. So I'm hopeful that that's a good sign on my rebuild.

What are the procedures for lubing the intermediate stepped pulley bearing and the idler wheel? Have looked online but haven't seen anything.

I'm using the original belt, and will continue to do so as long as it holds together and keeps speed. Need to replace the mirror, so not quite sure on the speed issue at the moment. I have a bag of pure talc that I got from a pool hall (scraped one of their talc cones; they were fairly surprised at the request...)
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Old 23rd January 2013, 06:33 PM   #12
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OK, so that was somewhat of a dumb question. Just pulled the idler wheel off and pulled the stepped pulley up as well. Will relube both and reinstall. This thing is much simpler that it would appear...

I have a single bronze bearing in the pulley itself. Not sure what that means for vintage. The serial number is 20101.
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Old 23rd January 2013, 06:36 PM   #13
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I'm assuming I should unclip the E-clip holding the felt down below the stepped pulley, clean that, re-oil, clean the shaft and bearing for both the pulley and idler wheel, and reinstall both?
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Old 24th January 2013, 03:52 AM   #14
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No, do not remove the felt unless the eddy current brake is difficult to move. Do not oil the felt! If the vane assembly in the eddy current brake needs lubrication use a little light teflon grease applied to the shoulder of the pedestal the vane rests on. Remove old grease first.

The stepped pulley bearing should be lubricated with a drop of 20wt oil.

Based on serial number I would guess sometime in 1960.
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Old 24th January 2013, 04:55 AM   #15
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Yup, figured the felt wasn't to be oiled. removed and cleaned it anyway. There was some old crusty grease in the stepped pulley, I cleaned that and re-oiled. Same for the idler wheel. The stepped pulley wouldn't spin for more than a few seconds, same for the idler. They both spin better, but neither is what I'd call particularly free spinning.

It's interesting - with every cleaning and relubrication, it gets quieter and quieter. And after each, I run it for a while, and that helps get it quieter as well. I still need to get the arm in shape, so I haven't actually listened to it yet, but that will come. I'm making sure the foundation is sound.

It's interesting too - for a table of this renown, it's comprised of a number of surprisingly simple systems.

Appreciate your thoughts on the date.
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Old 24th January 2013, 05:14 AM   #16
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Another question - as I try to benchmark and measure my progress, where do my efforts fall with respect to the motor rebuild? With the pulley attached, I have about a 33 second spin-down on the motor, belt unattached. With the belt attached to the stepped pulley, the spin-down is under 10 seconds. It is climbing though.

Where do those fall relative to the average?

I also have that light hiss I was describing earlier. It's gettig much quieter as time passes, but still audible from a short distance.
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Old 24th January 2013, 04:52 PM   #17
kevinkr is offline kevinkr  United States
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Takes about 100 hours for a motor with new bearings to break in.. Motors with original bearings and fresh lubrication should be there more or less immediately.

New belts generate significant noise and quiet down as they stretch slightly during use. Some brands of belts are quieter and more trouble free than others. (See my thread for lots of comments on belt quality)

The only spin down time IMO that is really relevant is the platter, and that should spin for a minute or more from 33rpm before stopping.

What is important to the drive line is that everything is properly aligned, clean, and lubricated. Even belt tension is going to affect the length of time the drive line spins after the removal of power.
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Old 25th January 2013, 02:21 PM   #18
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Hi Jd, Kevin,

Just my 2 cents.

When working on "self-centering" bearings, (yes, the same as installed in the TD124's motor), the way to center the bearings properly is to simply tap the motor's housing (gently) several times while the motor is running, according to my Dad the mechanical engineer. (using something like a rubber mallet or equiv) I, being the suspicious type, was hesistant to try this the first time, (no, not on my TD124's motor) but it has always worked perfectly for me ever since, yes, and including on my TD124.

JD, if you plan on keeping this table, I hope you have done what Kevin and I have done, that is, drilled out the rivets holding the bearings, replaced or cleaned and re-oiled the felts, and replaced the original bearings if necessary.

As you might have surmised, the journey might have just begun, but the excellent user-experiences we all have gone through here should provide an excellent resource, perhaps not available anywhere else.

Welcome to the club!


Gene
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Old 25th January 2013, 02:26 PM   #19
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Hi Jd, Kevin,

Just my 2 cents.

When working on "self-centering" bearings, (yes, the same as installed in the TD124's motor), the way to center the bearings properly is to simply tap the motor's housing (gently) several times while the motor is running, according to my Dad the mechanical engineer. (using something like a rubber mallet or equiv) I, being the suspicious type, was hesistant to try this the first time, (no, not on my TD124's motor) but it has always worked perfectly for me ever since, yes, and including on my TD124.

JD, if you plan on keeping this table, I hope you have done what Kevin and I have done, that is, drilled out the rivets holding the bearings, replaced or cleaned and re-oiled the felts, and replaced the original bearings if necessary.

As you might have surmised, the journey might have just begun, but the excellent user-experiences we all have gone through here should provide an excellent resource, perhaps not available anywhere else.

Welcome to the club!


Gene
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Old 25th January 2013, 05:35 PM   #20
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Thanks to the both of you for your suggestions. I have indeed lightly tapped the housing, and it helped center the bearings and quiet things down.

I did drill out the cover rivets, replace with screws, clean the felts, bake the bearings, re-saturate them, and reinstall. Much quieter but still a light hiss.

I have reinstalled the platter, and I get consistent spin-down times in the 1:45 range. So I'm comfortable there.

But I have to disagree that platter spin-down is the only one that matters. As I see it, there are four places where noise has an opportunity to enter the equation: the motor bearings, the stepped pulley, the idler wheel bearing, and the main bearing. Noise is a function of friction, and friction can be measured by free spinning time. So while there may not be an objective floor, I'd say the freer spinning all components are, the less friction there would appear to be, and consequently the less noise there would be. And I'll agree that the main bearing is the most important, as the closest to the disc, and the one with the most mass around it (and the most ability to translate rumble or friction/noise into the playback), but all have a roll (edit - role. No pun intended). Every mechanism in my mind should be as quiet as possible.

So now that I have my platter back on, I noticed (through my fancy new mirror) that my eddy brake doesn't appear to be slowing it down enough. Goes from way too fast to a little too fast. So I need to pull the platter off and adjust.

For those in need, I found a drop-in replacement mirror in a makeup compact at my local drug store. It's a bit wider and narrower, but it fits perfectly and tells me what I need to know. The old mirror was completely shot. Bonus points - I bought my wife makeup.

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Last edited by jdgordon; 25th January 2013 at 05:39 PM.
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