HMV Arm Guidance Needed

[gramophone-georg]

I am dealing with a tone arm from an HMV 32. I refinished the arm and base, and am trying to assemble it. There's a channel that 10 small bearing balls fit into, a race, and an inner piece that presses in from the bottom.

No matter WHAT I do, the balls come out of the race and all line up together, tipping the arm in the base making it bind. Incidentally, they were this way when I took it apart because of the binding issue as well.

What's the trick to keeping everything in place?
Yes, I have cleaned and greased everything.
Thanks for any tips/ advice.

[HMVDevotee]

Do 10 balls occupy the entire race? I ask because the 31A with the "fat" tonearm has over 20 balls in the bearing assembly and I was wondering if some repair prior to your ownership lost some of the balls in your bearing.

[Inigo]

Or there must be balls to fill the race completely, or a spacer is missing.
I don't remember the hmv thin swan neck tonearm, but the thicker one (later model for 5a soundbox) has a spacer with niches where the balls must feel into, and this maintains the balls separated between them and equally distributed along the entire perimeter of the race. This spacer is a big thin steel washer that goes in between, and it's inner circumference has small niches, round cutouts, where the balls must be placed. It goes in the middle of the assembly, so it is placed in front of the channel in the tonearm, surrounding it with the balls fixed in their positions along the race.

[gramophone-georg]

Do 10 balls occupy the entire race? I ask because the 31A with the "fat" tonearm has over 20 balls in the bearing assembly and I was wondering if some repair prior to your ownership lost some of the balls in your bearing.

Yes, I have all my balls. Thanks

[gramophone-georg]

Or there must be balls to fill the race completely, or a spacer is missing.
I don't remember the hmv thin swan neck tonearm, but the thicker one (later model for 5a soundbox) has a spacer with niches where the balls must feel into, and this maintains the balls separated between them and equally distributed along the entire perimeter of the race.

Right- this race has those niches- 10 of them. However, the balls do not stay in the race.

[gramophone-georg]

Finally got it. What a cluster! This has to be one of the absolute worst thought- out designs in the history of gramophones. I'm not sure if my constantly calling it a 'bloody tosser' helped or hurt. My accent was likely all wrong.

I wound up having to use heavy automotive grease to hold my balls in place and line them up with the niches on the race. Then it was an epic battle to get the inner sleeve and the three tiny nuts/ screws that hold it back in squeezing my balls just right, but without jostling my balls out of place.

THEN, I was rewarded for all that effort with- an arm that was really difficult to move even when the inner collar was set at its loosest using the little slanted slots on the collar where the screws poke through.

I cranked the inner collar tighter, then backed it off. That made it worse, so I got some Sili Kroil and dripped it in from underneath to help thin the grease. That helped, but there was still no way that arm could track, so I got a dull punch and rapped the base of the arm where it goes into the black arm base to settle things a bit, gave it another shot of Slil Kroil, and now she seems fine. Maybe it somehow knew I was about ready to use it to test my garbage disposal to see exactly how many HP it really has.

[Inigo]

I understand you... These tonearms are a nightmare! You need three hands, etc etc. Last time I disassembled one, I swore NEVER will do it again.!

[gramophone-georg]

I understand you... These tonearms are a nightmare! You need three hands, etc etc. Last time I disassembled one, I swore NEVER will do it again.!

Yeah, it's not on the list of things I'm going back for seconds on.

WAY too much work for this repurposed woodworm farm...

[Inigo]

But then they sound so beautifully...
I use frequently an old French hmv127 tabletop which is tatty, veneer bumps here and there, unadjusted woods here and there... All poor except the motor and cared for sound system. It sounds amazing... Yet better when I use a Meltrope III soundbox instead of the original. The Meltrope seems very well fitted for this horn. The sounds is incredibly warm and deep, perhaps a bit too loud!

[SteveM]

Wow, I popped onto the forum today for a couple reasons ... 1) to see if Georg was still working on his 32, and 2) to see if anybody was using Meltropes on their 32s or 31A's. This thread is like a 2-fer.

(I'll probably start a new thread anyway, but ...) while you guys are here ... I've been using a Meltrope isolator gasket on my 5b for use on my 32 and I'm pretty pleased with it (in lieu of an entire Meltrope, which I can't find). Question is, can I get a larger-bore Meltrope isolator gasket to fit onto my 31A's 5b? I think I read here awhile ago that someone was doing it, and was pretty thrilled with the result.