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I'm looking at buying a Seiko SNZH55 and doing my own Fifty five fathom mod. My problem is that I'm not a fan of the 7s26, I mean no offense and I'm going to get flamed for that but I also like to upgrade things.

I've seen that the 4R36 is the 7S26 but with hacking which is great, but what upgrades can be done further than that? Someone suggested a 9S85 but there are a few issues sourcing it and it's not on ranfft so I'm not clear on the dimensions. Plus, the expense.

What other options are there to upgrade from the 7S26?
 

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Yup, startime supply has them in stock for $115, though I believe it is less if you have an account, which you need to make before you buy from them anyway. Just say you're a small watchmaker, I don't think they'll sell to you if you don't indicate that you are a watchmaker.

The movement is known as the NE15B if you get the SII one, same situation as NH35a vs 4R35

Hattori / SII NE Series Japanese Movement, -- NE15: Star Time Supply
 

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I'd also note, using the StarTime supply link for a fair comparison, that the 4R35/NH35a is $38

Hattori / SII NH Series Japanese Movement, -- NH35: Star Time Supply

The 6R15 is a continuation of the 4R36, but it's just a tweak of the design to allow longer power reserve, slightly higher ratings on accuracy and slightly prettier finishing. If you can live without those and keep the ~$75 in your pocket the NH35a deserves credit for being a solid movement choice.

With all of these, realize that the height differs from the 7S26/7S36 and the stem height (how far below the dial the stem is) may differ as well. If you're doing something really custom, that may matter less, but if you're trying to drop this stuff in to an existing case then it may not be a direct drop in. I'm not even sure you can use the existing 7S26 crown and stem in a 4R or 6R. You may need to have that fabricated regardless.
 

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I'd also note, using the StarTime supply link for a fair comparison, that the 4R35/NH35a is $38

Hattori / SII NH Series Japanese Movement, -- NH35: Star Time Supply

The 6R15 is a continuation of the 4R36, but it's just a tweak of the design to allow longer power reserve, slightly higher ratings on accuracy and slightly prettier finishing. If you can live without those and keep the ~$75 in your pocket the NH35a deserves credit for being a solid movement choice.

With all of these, realize that the height differs from the 7S26/7S36 and the stem height (how far below the dial the stem is) may differ as well. If you're doing something really custom, that may matter less, but if you're trying to drop this stuff in to an existing case then it may not be a direct drop in. I'm not even sure you can use the existing 7S26 crown and stem in a 4R or 6R. You may need to have that fabricated regardless.
O - do you make a living on watches? I am always impressed by your off the cuff knowledge. Perhaps its not totally off the cuff, but you know things.
 

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I have a dangerously good memory...

My wife is the same way, except with credit card numbers and bank accounts... if she sees your CC#, expiration and CCV once... it's game over.

But no-- just a hobbyist.
 

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I'd also note, using the StarTime supply link for a fair comparison, that the 4R35/NH35a is $38

Hattori / SII NH Series Japanese Movement, -- NH35: Star Time Supply

The 6R15 is a continuation of the 4R36, but it's just a tweak of the design to allow longer power reserve, slightly higher ratings on accuracy and slightly prettier finishing. If you can live without those and keep the ~$75 in your pocket the NH35a deserves credit for being a solid movement choice.

With all of these, realize that the height differs from the 7S26/7S36 and the stem height (how far below the dial the stem is) may differ as well. If you're doing something really custom, that may matter less, but if you're trying to drop this stuff in to an existing case then it may not be a direct drop in. I'm not even sure you can use the existing 7S26 crown and stem in a 4R or 6R. You may need to have that fabricated regardless.
Oh dang! glad I read this before pulling the trigger on an NH35 to drop in my NH25 powered 8926. Just goes to show you, always do research before spending money!
 

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Oh dang! glad I read this before pulling the trigger on an NH35 to drop in my NH25 powered 8926. Just goes to show you, always do research before spending money!
From what I've read, they are direct drop-in replacements. Just check movement measurements, but I believe they're exactly the same. Lot's of people here have swapped 7S26s for NH35As. 0.11mm casing diameter difference is barely anything. Stem length will be somewhat unique to each case, so you would probably need to swap the stem and crown from the old movement to the new one.

Seiko Caliber NH25ASeiko Caliber NH35A
OrginJapan/MalaysiaJapan/Malaysia
Year Introduced(Please add to comments below)2011?
Diameter12"' (27.40mm)12"' (27.40mm)
Casing Diameter29.255mm29.36mm
Height5.32mm5.32mm
Jewels2124
Power Reserve> 41 Hours> 41 Hours
Beats Per Hour21,600 vph (6 vibrations per second)21,600 vph (6 vibrations per second)
Date?YesYes
Hacking?NO!Yes
Hand-Winding?NO!Yes, can also be manual-wind
CrownSee chart belowSee chart below
Shock-AbsorberYesYes
Quick Set Date?YesYes
COSC?NoNo
ModelsAdd yours to the comments belowAdd yours to the comments below

Measurements for NH35A or NH36A:Measurements for 7S25 or 7S26:
Size: 12''' (27mm)
Height: 5.32mm
Function:
3 hands / date
21,600 vibrations per hour (3Hz)
Stop second device
Quick date correction
24 jewels
Size: 12''' (27mm)
Height: 4.9mm
Function:
3 hands / date
21,600 vibrations per hour (3Hz)
Quick date correction
21 jewels
https://www.seikowatches.com/support/ib/pdf/SEIKO_4R15_16_35_36_7S26_35_36.pdf
 

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From what I've read, they are direct drop-in replacements. Just check movement measurements, but I believe they're exactly the same. Lot's of people here have swapped 7S26s for NH35As. 0.11mm casing diameter difference is barely anything. Stem length will be somewhat unique to each case, so you would probably need to swap the stem and crown from the old movement to the new one.

Seiko Caliber NH25ASeiko Caliber NH35A
OrginJapan/MalaysiaJapan/Malaysia
Year Introduced(Please add to comments below)2011?
Diameter12"' (27.40mm)12"' (27.40mm)
Casing Diameter29.255mm29.36mm
Height5.32mm5.32mm
Jewels2124
Power Reserve> 41 Hours> 41 Hours
Beats Per Hour21,600 vph (6 vibrations per second)21,600 vph (6 vibrations per second)
Date?YesYes
Hacking?NO!Yes
Hand-Winding?NO!Yes, can also be manual-wind
CrownSee chart belowSee chart below
Shock-AbsorberYesYes
Quick Set Date?YesYes
COSC?NoNo
ModelsAdd yours to the comments belowAdd yours to the comments below

Measurements for NH35A or NH36A:Measurements for 7S25 or 7S26:
Size: 12''' (27mm)
Height: 5.32mm
Function:
3 hands / date
21,600 vibrations per hour (3Hz)
Stop second device
Quick date correction
24 jewels
Size: 12''' (27mm)
Height: 4.9mm
Function:
3 hands / date
21,600 vibrations per hour (3Hz)
Quick date correction
21 jewels
https://www.seikowatches.com/support/ib/pdf/SEIKO_4R15_16_35_36_7S26_35_36.pdf
Thanks for Your share houston

Envoyé de mon SM-A320FL en utilisant Tapatalk
 

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I may be wrong but in terms of introduction (and therefore development) I think it went 7S - 6R - 4R. With the 4R based more closely on the 7S. The 6R was intended to be a more accurate movement with SPRON mainspring and the 4R a newer movement based on 7S specifically to add winding and hacking.

Anyway, I don't regard my 6R SARB as any higher end in terms of movement than my various 4R watches, arguably the newer 4R is my preference because of day/date and economy. I'd go 4R all the way if I was looking to upgrade from a 7S.
 

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Great sharing of info guys. |>
 
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