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One more after this, and then no more tonearms!

Sure. That's what they all say...

And then, you'll find a dusty old DD TT in a thrift store corner, with broken ruby bearings in the EPA arm for $15 and you can't resist. I know it'll happen. Never say never. ;)
 
Sure. That's what they all say...

And then, you'll find a dusty old DD TT in a thrift store corner, with broken ruby bearings in the EPA arm for $15 and you can't resist. I know it'll happen. Never say never. ;)

Should’ve said the last I’ll do for others. I’ll work on my own stuff all day.
 
And then, you'll find a dusty old DD TT in a thrift store corner, with broken ruby bearings in the EPA arm
I haven't read this whole thread but is this a common problem with these older TT, broken ruby bearings?
A bad design or Primitive Pete owner handling causing the problem?
Just curious as I don't know of other TT's have arm bearing issues.
TIA John.
 
I haven't read this whole thread but is this a common problem with these older TT, broken ruby bearings?
A bad design or Primitive Pete owner handling causing the problem?
Just curious as I don't know of other TT's have arm bearing issues.
TIA John.
Oh. Linn arms are famous for becoming sticky
 
I haven't read this whole thread but is this a common problem with these older TT, broken ruby bearings?
A bad design or Primitive Pete owner handling causing the problem?
Just curious as I don't know of other TT's have arm bearing issues.
TIA John.

Actually, JP has way more experience with Technics EPA arms than me. I've only ever seen a few with shattered arm bearings and sadly, they were written off.
 
I'm not aware of many arms with ruby bearings. For Technics it was only the EPA-100, EPA-100MKII and EPA-102MKII.

The issue is always rough handling, and at 40+ years old the majority of the ones remaining have had rough handing at some point in their lives. I don't see shattered bearings too often, but chipped bearings are very common. And, when they've been handled rough enough to damage the balls, typically the pin races are indented as well. I replace them with Si3N4 balls and re-grind and polish the pins. Using Si3N4 is an improvement over jeweled bearings with the added benefit of the arm being no more fragile than any other typical arm.

For all the top Technics arms that are approaching this age, lubricants that are turning to glue is a problem, so a complete clean and re-lube is needed. On the older EPA-100 the wire insulation has typically done a fair job of corroding the copper, so a re-wire is also indicated. Most people want to re-wire them regardless. There are other small issues to be taken care as well.

Much like their serious 'tables, give them a thorough going over and as long as you don't abuse them, they should last another 40+ years without issue.
 
I'm not aware of many arms with ruby bearings. For Technics it was only the EPA-100, EPA-100MKII and EPA-102MKII.
If I was ever to get into vinyl again my choice would be for a air bearing SLT arm.
This one looks like a beauty.

51520730-9dcc-49fa-839e-4b412b7c4141_1500x.jpg
 
Oh a little shot of WD40 will fix them right up.
LOL JK.
That works for a while - then even worse. I've been thinking to rebuild it but I've restarted another hobby after 45 years...first 1:72 model brush painted....

1718034653948.png
 
Primitive Pete owner handling causing the problem?
Now there's a boy who took a shop class (maybe a serviceman) and saw the infamous 16mm movie. ;)
 
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I've been thinking to rebuild it but I've restarted another hobby after 45 years..
Just don't be sniffin that glue, it causes brain damage. DUH LOL
 
If I was ever to get into vinyl again my choice would be for a air bearing SLT arm.
This one looks like a beauty.

51520730-9dcc-49fa-839e-4b412b7c4141_1500x.jpg
Looks excellent. Only problem with that kind of arm is that it cannot be used on a TT that is spring mounted because atrm moves
If I was ever to get into vinyl again my choice would be for a air bearing SLT arm.
This one looks like a beauty.

51520730-9dcc-49fa-839e-4b412b7c4141_1500x.jpg
Looks like a beauty. Only thing about an arm like that is that it should not be used on a TT that is suspended on springs, because as the arm moves from side to side, the TT will tilt as the weight shifts, putting the TT out of level, and then the arm will exert a sideways force on the stylus. I had the Eminent Technology version of that type of arm mounted on a Linn Sondek LP-12 TT and that was a bad combination. I had to jam the TT to keep it level as the arm moved inward toward the center spindle during play, and that ruined the TT's vibration isolation. So that arm should be mounted on a solid part of the TT that does not shift out of level with arm excursion.
 
Only thing about an arm like that is that it should not be used on a TT that is suspended on springs, because as the arm moves from side to side, the TT will tilt as the weight shifts, putting the TT out of level,
Interesting. I guess it would also depend on the arms mass. I didn't think there'd be enough to
upset the tables level over the short maybe 4" horizontal movement..? But definitely highly possible.
I ran a H-K ST8 for 20 some years, rock solid reliable and never drifted out of arm timing. I hadn't been
using it in years so when I went to rip all my LP's at retirement the belts had hardened up a bit.
So I replaced all 3 belts and cleaned everything up, then proceeded to rip something like 300 LP's without
a hiccup. Great little design that H-k ST8 w/ Rabco design arm. Ultra low mass was a great match for high compliance
MM needles.
IMG_0999.jpg
 
Just for now, or for good?

One gets to the point where other people's jobs queue up, they take way too much time and your own projects and passions that got you into the whole thing in the first place get pushed further and further back down the line. And we all get older.
 
One gets to the point where other people's jobs queue up, they take way too much time and your own projects and passions that got you into the whole thing in the first place get pushed further and further back down the line.
And start to make it no longer the fun it was back "in the day" ;)
 
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