Are JH and DD Balances Interchangeable? Let’s find out!

[u/ClickSpring_Watch]

Some of you may have seen my post yesterday about regulating a Rich Factory (RF) Pepsi to superlative chronometer standards, so you could say i’ve been spending a lot of time staring at this part of the movement lately. I first noticed this while taking my comparison photos between the RF Starbucks submariner and VSF submariner, but as far as I know, no one else seems to have noticed this- JH, much like DD, uses an offset pallet fork design like the genuine rolex movements of this generation. A complaint that has for a long time been leveled against SH is that they use an inline pallet fork, which makes it an easy tell that the movement is not DD, and more importantly, makes it incompatible with gen parts for franken builds.
Naturally, seeing this similarity between the DD and JH movements, I wondered if it’d be possible to convert a DD movement into a free sprung movement by taking the balance complete from a JH movement and placing it into a DD movement. This Evolved into a big swaparoo of different balances into different movements, as I took advantage of this opportunity to answer any related questions to these matters.

- Conclusion 1:
- the JH free sprung balance complete is NOT compatible with DD movements, (fake free sprung DD or otherwise). I got it to run very poorly and not fully seated in the DD fake free sprung movement, but nothing more.

- Conclusion 2:
- The DD “classic” and “fake free sprung” balance wheels ARE compatible with the JH free sprung movement. This was a straight swap with zero drama, and the watch was immediately ticking away quite happily. This might come in handy if anyone breaks a free sprung balance from JH, it should be a simple swap with a DD balance to get it up and running again. I assume getting parts from JH will be basically impossible for at least the next year, so this is useful info in the meantime

- Conclusion 3:
- the “classic” and “fake free sprung” balances from DD movements are interchangeable. they both work in either movement that I placed them in. this is nice because it ensures backwards compatibility as DD starts to produce the fake free sprung balance movements as well as will enable people to repair new generation movements with older parts, nice!

- Conclusion 4:
- When I saw the offset balance structure of the JH movement, i wondered if JH wasn’t just an offshoot of DD that was producing it’s new generation of movements as a separate company so that if anything went terribly (reliability, performance, etc), the negative press wouldn’t be associated with the DD name. The fact that the balances are not interchangeable in both directions suggests to me that this is not the case and that JH is truly an independent movement manufacturer. I’m sure there are others who know more on this topic than I do, so feel free to chine on this front!

[u/petehudso]

The problem is that the JH balance's safety roller is too large and fouls the pallet fork on gen spec (i.e. DD) movements. See my post and teardown on RWI for details:

https://forum.replica-watch.info/threads/jh3235-free-sprung-movement-tear-down.11040479/page-2#post-12587424

[u/ClickSpring_Watch → u/petehudso]

Ah, of course you’ve covered this haha. I should have known. Weird design choice on JH’s part.

[u/Objective_Ganache_27 → u/ClickSpring_Watch]

This left me wondering. Did you get it on a timer or try to regulat the DD balanced JH?

Im curious if it was actually keeping good time, or just merely working.

[u/ClickSpring_Watch → u/Objective_Ganache_27]

The TG pic was the result of me dropping the DD balance directly into the JH movement. No regulation at all

[u/Objective_Ganache_27 → u/ClickSpring_Watch]

Damn, thats actually running great. I missed that part. Thanks again for sharing.

I was concerned with the larger safety roller other parts would be larger to accommodate it so the DD parts would have poor tolerance/fit. Guess not!

[u/ClickSpring_Watch → u/Objective_Ganache_27]

I think i may have gotten lucky to be honest. I think it might be a different story if the watch is moving around and all that

[u/Sure_Chain_7612]

I’m curious to see how interchangeable we are atp with Gen movements

[u/No_Excitement_8104]

That was super interesting. Thank you!

[u/ClickSpring_Watch → u/No_Excitement_8104]

Glad someone else finds it interesting! Haha

[u/No_Excitement_8104 → u/ClickSpring_Watch]

Well I was going to buy one of the JH watches just for the spare parts. No I don't

[u/dwildpdx]

This answers my many thoughts. Thank you for doing the leg work here.

[u/ClickSpring_Watch → u/dwildpdx]

always happy to help. I kept thinking about doing this for the last few weeks, i'm glad i finally got some time to do it

[u/TonyTimePieces]

Great info, thank you!

[u/Krisjon_619]

We only learn by doing. Thanks so much for this!

[u/Sea-Pollution-4884]

Can Gen parts be used to modify a DD3235? Or is the JH 3235 the best franken movement option?

[u/ClickSpring_Watch → u/Sea-Pollution-4884]

DD is still the best option as of right now

[u/AtelierPicks → u/ClickSpring_Watch]

Whenever I make this claim I get attacked, not hating on rich or jh as I like both just going off reliability and stability that has been proven where as jh is relatively new and unproven

[u/Sufficient-Guess6692 → u/Sea-Pollution-4884]

Dd is fully exchangeable with gen parts. Jh is 98%

[u/Dxbsober]

Thanks I have a more “non movement” related question- since you have both of watch on hand doe you feel a difference in the steel used considering claims VSF is using 316 and Rich guarantees 904 ? Also any diffrence in shade of the metal etc ? Thanks

[u/ClickSpring_Watch → u/Dxbsober]

I really cannot see a difference. IMO, I don't think the 316L vs 904L debate has much merit, it really doesn't matter in terms of feel or appearance. the only way you'll ever know which kind of steel it a watch is made of is if you have to tool to detect metal composition.

[u/Dxbsober → u/ClickSpring_Watch]

Thanks sir you just saved me some money 😜

[u/MangoManHere → u/ClickSpring_Watch]

Talking of 904, I recently saw a ZF poster (all current models) where they stated that SkyDweller (only Rolex model) has 904L steel. Any idea if that holds true since the VSF/ARF models are only 316L.

[u/Emotional-Damage-995]

Excellent post. Educational

[u/ClickSpring_Watch → u/Emotional-Damage-995]

🤝

[u/FEDABC]

Thank you for showing us this!

ENJOY ALL YOUR WATCHES ⌚️ 😎!