New WM-DD center gear prototype is here (EDIT - final version is here)

Yes. Has to be and of course you cannot have metal on plastic contact. Well not for long anyway. Still I would like to see a YouTube video of the process and the finished reassembly. The description is a bit light on detail. Is the process some sort of ring clamp that closes the gap on the cracked plastic gear?. How would that work anyway.

 

Ciao a tutti, ieri ho trovato un wm DDII probabilmente di mio padre, ho provato ad accendermi ma sembra morto, la luce rossa rimane spenta e non succede nulla se provo a premere start o qualsiasi altro pulsante.
L'ho aperto oggi e ho notato che c'è una marcia rotta, cosa potrei fare per ripararla?

 

Looks like there is another seller for a new Sony centre gear:
https://www.ebay.com/itm/224571235277?hash=item34497d1bcd:g:DzAAAOSwr0RhwhwZ

A nice coloured one!
But not sure how it is connected to the metal of the old gear?

 

What difference does the colour make, no one is going to see it once it's inside the unit. Kind of pointless.

 

Prefer Marian's kit. This one looks like it needs to be glued? Anyone know how it attaches? Atleast with Marian's kit, if it does break in the future, it's easier to replace and much cleaner. Only some screws and and away you go with a working DD again. I still have two kits left over. Might need to buy more DD Walkmans.

 

Hi there
I tried those and they are fine very easy and fast to install they just clip by pressing on the metal of the center gear takes less than a min. If you need to replace, which I doubt, just press the metal gear to separate it. There is a video on YouTube.
I hope it helped

 

OK, the colour is pointless, but I like it when an electronic device has been thoroughly thought of in the way how it has been constructed inside.
A neat layout and good setup in an apparatus is in my opinion mostly a sign of good quality.
And I know how it is inside. Just like nice underwear

 

StaticAudio No one is disputing a good clean layout, but a coloured wheel in this case?

 

Well, black, it's just black isnt't it?

 

Yes black is black, what is the selling point of the coloured ones? Does the seller think people will rush out and dump their perfectly good working none broken one's and buy the new coloured one's?

 

If I had to replace a broken centre gear I would go for the best one for replacement, and if that one is pink I couldn't care less.
And not swap a good one for a coloured one, no, of course not.
Maybe the sellers' plastics give a random colour when it hardens...

 

Hello ,

I want to share my experience with the plastic center gear that is been sold on eBay.
I bought many gears from Marian and they are working well.

I tried this gear from eBay and I have to say I am very pleased by it. It has a couple of advantages

1. Its more flat because it uses no screws and you don't have to sand it to get it flat.
2. The alignment is not so sensitive when the claw assy reel has been broken and repaired. I experience with Marian's gear that FF gear is sometimes scraping. This gear seems to have not that much of a issue when the alignment is not 100%.


I don't know the material of this gear, if its made of POM it will get the same issue as the original gear in the future.

I have made 3 video's so you all can see it for yourself.

Part 1:



Part 2



Part 3

 

@tomtom87 I have similar experience regarding the 2 types of gear. The ebay one with design similar to original is a little better in regard to functionality.
That is when installed correctly, I have seen ones that have been bent during installation and I had to replace it again.

However, I am more concerned with the long-term reliability, given it's likely the gear is made of POM.
My recommendation for people reading this is the following:
- when the alignement of the mechanism is perfect, use Marian's gear (which will be most of the time in my experience);
- when the claw assy reel has been broken and repaired, use the ebay one in case you can't get FF to work without scraping;

Marian's one would be ideal in all scenarios if it was perfectly round, which it's not. It has a little bit of a lateral wobble, which combined to the fact that gear is
thinner than original and a tiny misalignemnt will cause FF scraping in some situations (which are rare).
Probably this has somthing to do with the manufacturing process, as the gear does not cool down evenly.

 

I think this is a very good conclusion! But Marian's gear is also made of POM is it not?

• Quantity: 1
• Package content: one gear ring, one metal ring, 6 screws
• Material: POM, steel
• Colour: white
• Functionality was tested

 

It is indeed POM as well, but Marian's one is not a tight fit on the metal disc (there is just a tiny bit of play), while ebay one is press fit (although not as firm as original).
Also the screw holes are a little larger than the screws, so to me it seems a lot less likely for this one to crack long-term.
And even if it were to crack (hypothetically), it would only have a hairline crack (and likely still usable with no noise) and not a 2mm crack one as original ones do.

The best design by far is the one used in early WM-2s, where there is no metal disc and the entire gear is made of plastic.

An example can be that from gears used in WM-EX series (https://stereo2go.com/forums/threads/wm-ex-series-tac-tac-sound-repair.7108/), many are still intact with not even a hairline crack.
I think it has to to with storage conditions, as POM contracts with temperature increase, so probably those stored in high temperatures/in the sun are more likely to have a crack in the gear.
Those are glued to a metal disc, so are even more likely to fail that the screw mount design.

 

Thank you very much for this view, I thank you are right!

 

Hi I have a WM DD first model 1982 with broken central gear. What type of gear you recommend to me? I read a lot and no sure what kind to use - with skrews or not?
Thanks!

 

Hello, if its your first repair I think the plastic gear is easier.

 

Yes for mi is first repair.I want to use better plastic gear.Do you have experiance with this gear?
Thanks!

 

@Ivajlo B Please read posts #332 and #333 (5 posts before yours) as we already stated the experience in regard to that gear. Use it without any worries.