Is there any rescue for a borked Rega Bias?

[Montycat]

The cantilever on this cartridge was bent back in a dogleg. I straightened it, kinda, but don't really want to play it.

Any thoughts? @needlestein ?

 

[Montycat]

Well thanks for that!

Here it is with a cantilever from an aftermarket M95ED. Now to test it!

 

[Montycat]

So far not good. I will be testing more later but I had weird noise from one channel and then nearly no volume. I will get out my Technics Sl-1700 later this weekend rather than my Denon with AudioCraft arm. It's easier to do quick adjustments on that.

I put it aside for now and have been listening to my Grace with it's hack stylus instead.

The Rega does not owe me anything, except for potentially one cheap Shure type stylus.

 

[Montycat]

I think it is MI now but will try to check later tonight or tomorrow. If I can find where that cantilever went that is.

 

[Montycat]

Well I have confirmed MI and that both sides are good. I put in a damaged but kind of playable ADC QLM cantilever and it works. It's not somethig I want to use but I think I will add some 740s to my next VOM order.

 

[Montycat]

Success!

This is playing now with a cantilever from the Red Ed type stylus I earlier modified to fit my Grace F9. Since I also hacked a Technics stylus body to fit the Grace this was just hanging around.

Rega Bias cartridge. by Buhduh, on Flickr

 

[Fishead]

Hey guys, not wanting to go off topic and hope this is not, but if so just let me know and I'll start a new thread. I have been reading with interest how you are just pulling cantilevers out of cartridges and sticking "new" ones in there. Is that something that can be done with any cartridge or just certain ones? Does the cantilever connect to anything inside the cartridge or just sit there between coils, or magnets? Sorry if this is a dumb question.

 

[Fishead]

One reason I ask is that I have an old Benz Micro MC20E2 with a broken off cantilever. Always liked the way that sounded, even though an entry level cart from them, before the cleaning lady took it off with one fell swoop of her dusting tool.....OUCH!!!

PS - there is a small stub of what was once the cantilever left in the suspension.....

 

[Fishead]

How kind of you to provide such a clear explanation! I really didn't think so, but thought I'd ask just the same. That old Benz Micro cart was on my Nottingham Space Arm/ Spacedeck when I got it.....only lasted a couple weeks before the cleaning lady made short work of it. This was my fault entirely (should have covered it) and she never suspected that what she did caused me such a major OUCH! I just let it go and got a cover for the table and now things are safe.....safer anyhow. Thanks again, sir, and my best to you!

 

[Montycat]

Once you get the conical tip in there, you might need to adjust SRA either at the arm or the tip of the cantilever. I haven't really evaluated whether the Nagaoka and the Bias have the same cantilever angle or not.

Right. I have tried to compare it to what I can see online but it's a bit of a guessing game as there are no pictures from the right angle. I'm in the ballpark though and it sounds ok so I am not too worried.

 

[bang4buck]

Thanks @Montycat and @needlestein for sharing this information. Based on this thread, I grabbed a damaged Rega Exact off ebay for a modest amount. Both coils have continuity. The cantilever is kinked and severed right where it enters the cartridge body; I have the fragment. Assuming the Vital tip still has some life left, I imagine I could reattach it with a cactus needle splint. This might be easier than trying to pull the stump out of the cartridge, as there is nothing to hold on to with tweezers.

So, in your experience, the cantilever is simply held by friction in the elastic "diamond"? Do I need to be careful not to push it out the wrong way, into the body?

 

[bang4buck]

Yeah, I was pretty fast for once. I figured even if the body turned out to be dead in one channel, as happened to you, at least the tip could be used for some Frankencart. It came in a complete Nagaoka MP-110 package, too. Bit of overkill for the condition it's in but I'm not complaining. No points for guessing what replaced the Rega in the seller's setup.

The cantilever tubing is oval, i.e. wider than tall. Haven't seen that before. It's not going to make the splinting any easier. We'll see.

 

[bang4buck]

Hmm, I don't think that's what it is. The oval shape is very uniform and goes all the way to the "spoon" part. You can actually just see it in that listing photo above.

 

[bang4buck]

A couple of lousy phone plus loupe pictures. Same scale in both views. I'd say that's about 2:1 width to height.

 

[bang4buck]

The hole in the suspension is of course shaped to accept this oval, so shoving your basic circular cantilever in there is not going to work well. I'd have to flatten at least a section of it to the right size, while keeping 90 degrees azimuth.

Well, that's only Plan B, anyway. Still hoping to splint the Vital tip back on. No luck with pulling the stump, though. There is nothing left to grip with tweezers. I may try gluing a toothpick or a piece of string into it and pulling it out by that. Another thought is opening the body. I suspect a hairdryer would soften the glue/tape that holds the metal shield.

 

[bang4buck]

No, the stump is there, but it broke flush with the elastomer all around. My tweezers could use some grinding but there's a real danger of pushing it in further and/or tearing the tubing wall so I gave up trying to grab it.

The body material is supposedly Pocan, which Google says is heat resistant to 150 deg C. Not sure I would even be able to push it out from the inside with the shield off, though. I can't find an internal picture of these anywhere, except tiny here: http://www.hifiplus.com/articles/meet-your-maker-hi-fi-visits-rega-research/?page=7

Is that tech just posing with the soldering iron, or is he warming up the glue?

 

[bang4buck]

Well, those plastic trays in the picture seem to have a lot of black gunk on them. I bet that's the adhesive. I see black in the seams on mine. And that's a lot of surface area for gluing. It's not going to come off easily.

 

[bang4buck]

By the way, linked on that page is a review of the Aphelion MC which contains this interesting tidbit:

... a rhomboid pivot pad suspension with butyl rubber that has a molecular migration characteristic, in other words, it bonds to the cantilever and the cartridge body over time without the need for any adhesive

In the photos, the suspension looks very similar to what I see on the Exact. Could well be the same stuff across the line.

 

[DavidTT]

This thread is a perfect example of the goodness of this forum. Practical DIY at a very high level. Love it! Thanks all who posted in this thread, from those of us who can add these tidbits to our DIY arsenals.

 

[bang4buck]

Success! It took some doing but a hairdryer and an X-Acto knife was the way to go. Popped off unexpectedly at the end and ripped the ground wire, but the coils are okay (phew).



Explains what that soldering iron was for. Not visible in the photo but I do think I can get in between those pole pieces and push the stump out. Another time though.