[mlundy57]

The Rega RB303 tonearm that caused the accident with the Zephyr cart has an issue I can't fix that I think is directly related to the accident. It will not static balance. With the tracking force and antiskate both set to zero, as long as the counterweight is too far forward the arm stays put. However, when the weight is adjusted backward, as soon as the arm starts to float it swings to the outside.

The table is perfectly level so that's not the problem. Does anybody have any ideas why this is happening and how to fix it?

Thanks

[sunnydaze]

Shot in the dark here, but OL arms are highly upgraded versions of Rega arms, so maybe this (watch at 6:25) is going on in your situation?

https://www.youtube.com/watch?v=j_fq8oGDZTY

Keep in mind this is a strong outward pull on a "floated" arm as opposed to a gentle (and normal) outward pull, as Mark explains at 2:10 of the same video.

[sunnydaze]

My other thought is that maybe the anti-skate mechanism is defective such that it's applying outward bias, despite being set to zero.     

Sorry to hear about your Zephyr mishap.  I have the same cart and it is a fine performer.

[mlundy57]

I’ll try twisting the arm around tomorrow and see it that helps, thanks

[Letitroll98]

I can't remember exactly, but I believe there was a problem with the old RB300 where the antiskate magnet came loose or was misaligned.

[mlundy57]

I can't remember exactly, but I believe there was a problem with the old RB300 where the antiskate magnet came loose or was misaligned.

Any idea on how to check to see it tis is the issue?

Still looking for the right tool to remove the arm rest. It has to be removed to spin the around to see if it is excessive twist in the wires

[Letitroll98]

That's all I have in my memory, it was definitely a malfunction with the RB300 magnet, but you don't have that arm, you have the newer model.  There was a fix, it wasn't a fatal error, maybe look for it online.

[sunnydaze]

Deductive reasoning.....

If you rotate the arm a full turn counter-clockwise and the problem is not solved, or the floated arm now drifts inward, then a cable kink at the bearing housing / pivot point is not the problem.

You can then safely assume that the anti-skate is defective.  Either that, or if the outward drift is just slight or mild, then it is normal.  As explained by Mark Baker in the video I linked earlier.  My OL Encounter Mk3c arm has this slight outward drift when floated, even with the bias disengaged.

What else is there?   

[mlundy57]

Thanks for the suggestions. So far still stumped. Can’t do the turn the tonearm around trick. The arm lift is in the way and I can’t get it off.

I had already ordered a new Woody tone arm from Pete Riggle. I’ll save the repaired Zephyr for the new tonearm.

The Ortophon 2M Black is back on the RB303 and the lift is off the TT. I still have to be careful when cueing the arm down so it doesn’t swing out too much and miss the lead-in groove. That’s nothing new and will suffice until the Woody gets here in three or four months.

[sunnydaze]

When playing records I would set the bias to zero...if you haven't already done so.

[mlundy57]

When playing records I would set the bias to zero...if you haven't already done so.

Yep, tried that. Mitigates some but not enough

[sunnydaze]

Yep, tried that. Mitigates some but not enough

Sorry, I misunderstood.  I thought you said you removed the bias only when "floating the arm" with no VTF,  to test things out.

Since you already have too much side bias, I figured setting anti-skate to zero when playing a record is a good idea.  Wasn't sure if you had done that.

[Norman Tracy]

Looking in a Rega tonearm manual in this case for the RB3000 (https://www.rega.co.uk/download/rb3000_user_manual_en_02.pdf) I found this (bold emphasis added):

With the cartridge correctly mounted and with the stylus
guard removed, ensure that the tracking force dial (a) and
bias adjustment (b) are set to zero. Adjust the balance weight
(c) until the arm is “floating” with the stylus approximately
1mm clear of the record. Note: It is normal for the arm to
swing back towards the arm clip position even with the bias
set at zero. Therefore it is advisable to gently hold the arm
bearing carrier (just below the tracking dial) thus preventing
horizontal movement during the balancing procedure.

End quote.

To me this says Michael's (and others) Rega arm's tendency to resist achieving perfect static balance rather drifting outward with tracking force and anti-skate set to zero is as the saying goes "not a bug (or broken), its a feature". Rega is not afraid (perhaps even proud) to march to the drummer they hear, like their longstanding refusal to provide easy VTA (vertical tracking angle) adjustment favoring a more rigid mount they have selected the design trade off they feel is optimum. Finding that in the manual my guess is the magnet in the anti-skate mechanism cannot be moved far enough away to not have an effect.

[mlundy57]

Looking in a Rega tonearm manual in this case for the RB3000 (https://www.rega.co.uk/download/rb3000_user_manual_en_02.pdf) I found this (bold emphasis added):

With the cartridge correctly mounted and with the stylus
guard removed, ensure that the tracking force dial (a) and
bias adjustment (b) are set to zero. Adjust the balance weight
(c) until the arm is “floating” with the stylus approximately
1mm clear of the record. Note: It is normal for the arm to
swing back towards the arm clip position even with the bias
set at zero. Therefore it is advisable to gently hold the arm
bearing carrier (just below the tracking dial) thus preventing
horizontal movement during the balancing procedure.

End quote.

To me this says Michael's (and others) Rega arm's tendency to resist achieving perfect static balance rather drifting outward with tracking force and anti-skate set to zero is as the saying goes "not a bug (or broken), its a feature". Rega is not afraid (perhaps even proud) to march to the drummer they hear, like their longstanding refusal to provide easy VTA (vertical tracking angle) adjustment favoring a more rigid mount they have selected the design trade off they feel is optimum. Finding that in the manual my guess is the magnet in the anti-skate mechanism cannot be moved far enough away to not have an effect.

Thanks,

Since the arm also exhibits the same outward movement with 2g tracking force applied and anti-skate set to zero when the arm is cued down to start play and when it is is lifted off the record at the end of the side, I'm guessing it is unsolvable and a good reason to not remount the expensive cart to this arm.

I'm probably just going to sideline the turntable until the repaired cart and new tonearm are both in house.

[sunnydaze]

Thanks,

Since the arm also exhibits the same outward movement with 2g tracking force applied and anti-skate set to zero when the arm is cued down to start play and when it is is lifted off the record at the end of the side.....

That shouldn't happen.  There is a problem.

[mlundy57]

Update:

The problem has been solved. It still swings outward when trying to static balance, which has been pointed out as normal. However, it no longer swings outward when the cuing lever is dropped nor does it swing out when the end of play lift activates.

Spinning the arm around counterclockwise wouldn't work. There is an internal stop which prevents this. Also, twisting the wires clockwise from underneath the arm wouldn't work. The plug which the wires pass through is fixed so it cannot be turned.

What did work was something I had no idea was the issue. The cuing arm rest is not in a fixed position like I thought. It can rotate around it's axis. The reason the arm swung out when lowering to play is that the position of the arm rest had been rotated in toward the arm base on the plinth side. This resulted in the arm rest not being perpendicular to the tonearm then positioned to lower onto the record which resulted in the outward swing. Basically sliding off the rest. Rotating the left end of the arm rest towards the front of the plinth enough positioned it so the arm was perpendicular to the tonearm while lowering. This keeps the tonearm in place as it lowers.

The sliding off issue at the end of the side was the same thing. The cuing up rest had been spun so it was not perpendicular to the tonearm as it was raised which resulted in the outward movement that broke the stylus and ruined the LP.

Lesson learned, anything that either lowers or lifts the tonearm has to be perpendicular to the tonearm when the mechanism activates. If it is skewed too much toward parallel there is not enough friction to keep the tonearm in place.

Thanks for all the help and suggestions.

Mike

[sunnydaze]

Glad you got it worked out!!   

I was going to mention a possible problem with the cueing platform that actually lifts the arm -- since I too once had a similar situation with a "non-flat" platform that caused the arm to swing when cued during normal operation -- but since I was too focused on your "floated" arm situation, I did not.

How does this cueing situation explain the arm strongly swinging out when "floated"?  I thought you said that was also happening, in addition to arm swings during normal cueing.   Definition of "floated arm" is to find the center of gravity such that with zero tracking force and zero anti-skate the arm just hovers over the record surface.  Cue should not come into play.  It's not used when floating the arm, and it's actually impossible to float the arm properly when using the cue, as it usually prevents the arm from obtaining its balanced float position, which is typically below the cue height.

Too bad about the definitional / nomenclature confusion, we could have solved it much sooner since I had a very similar situation and I solved it just as you did -- simply rotate the cueing platform on its own axis.   

[mlundy57]

It turns out the outward movement when floating is normal for this arm. Norman found instructions from Rega saying this outward movement was normal and recommends constraining the arm from sideways movement when balancing it.

Initially I thought the two types of outward movement were related so fixing one would fix the other. Turns out that was not the case.

[sunnydaze]

It turns out the outward movement when floating is normal for this arm. Norman found instructions from Rega saying this outward movement was normal and recommends constraining the arm from sideways movement when balancing it.

Initially I thought the two types of outward movement were related so fixing one would fix the other. Turns out that was not the case.

Correct.  As Mark Baker at OL said in that earlier video: "mild" outward movement of a floated arm is normal and no cause for concern.  That's why I provided it.  My Origin Live arms do the same.  But do not swing out w / VTF applied and in normal use.  If they do, it's a problem with the cueing platform -- as you discovered. 

I initially thought you said when floated your arm swung "strongly".  I guess I was confused.  An unfortunate and more frequent occurrence in my advancing years.     

[mlundy57]

Correct.  As Mark Baker at OL said in that earlier video: "mild" outward movement of a floated arm is normal and no cause for concern.  That's why I provided it.  My Origin Live arms do the same.  But do not swing out w / VTF applied and in normal use.  If they do, it's a problem with the cueing platform -- as you discovered. 

I initially thought you said when floated your arm swung "strongly".  I guess I was confused.  An unfortunate and more frequent occurrence in my advancing years.     

To me it did seem like a strong swing. I didn't time it though. Even if I had I don't think there is a precise definition of a strong vs a weak swing.