As some of you already know I love watches, especially the automatic watches.

I pulled the trigger on one of Seiko’s new SKX replacement watches, a SRPD79. These new watches are somewhat controversial in that Seiko addressed and corrected some of the complaints with the SKX while removing a feature that was loved and in my opinion a stupid thing to remove.

Seiko reduced the water resistance on these watches from 200m to 100m and took away the screw down crown. That sucks but one good thing Seiko did was update the movement with the newer 4R36 movement. Why is this good? The watch finally has hacking or the ability to stop the second hand when setting the watch. I struggle to get excited about watches that don’t hack so this was a good improvement to me. Seiko also added a display case back which is nice especially when you consider this is a OEM factory part rated for 100m. Arguably the best thing Seiko did though with the new watches is offer LOTS of variants with different dials, colors and sometimes questionable styling. But variety is a good thing I think.

Given my love of tinkering with things I bought this new Seiko with the intention of tearing into it for parts. I’m going to remove the entire movement, dial, hands, everything and attempt to put it into a PDV (black) cased Seiko Turtle. I believe it should swap right in without too much effort. I’m also hoping the display case back is compatible as it would be nice to have a display case back that I can trust to keep water out when I’m at the beach, pool and on the boat.



This is the new watch being used for parts.


The complete movement is going into this spare Save The Ocean Turtle I have which has a MUCH better looking case, a screw down crown and 200m WR.


I’m also going to change the bezel and insert to something blacked out and probably ceramic.

When I’m done it should be somewhat similar to my Limited Edition (and now sold out) Steinhart Phantom Green Ocean GMT.

This message has been edited. Last edited by: stickman428,

Cool project! The drop in water resistance doesn’t seem all that egregious to me, but getting rid of the screw down crown along with that doesn’t make a lot of sense. But what do I know?

I like that Steinhart.

Thanks! I was originally concerned with how hard it would be to read in low light and whether it might be too stealthy. As it turns out my concerns with the Steinhart were a non issue, the hands do a great job catching the light and the indices have a small silver ring around them too so they reflect light well too. It’s surprisingly easy to read in low light though the lume is pretty awful. I suppose given the black color of the lume I should be happy it has any luminous qualities at all.

The Steinhart looks so different from all my other watches that it was finding it’s way on my wrist quite often. Since Seiko doesn’t make a turtle quite like this Steinie I figured I would just try to make my own.

Hopefully I don’t break anything.

I get that most people who use these watches are not divers. But still, if you are billing your watch as water resistant to any degree, especially 100m, how do you not have a screw-down crown? Does it really save that much money?

From what I’ve gathered in my research online a screw down crown is actually not necessary to get decent WR. There are internal seals in addition to the one on the screw down crown that will keep water out well enough. I believe there is even a diver on the market with a 300m WR and no screw down crown but it is the exception not the norm.

This was undoubtedly a cost saving move by Seiko. The crown tube on their screw down crown watches are apparently epoxied in by Seiko and can be drilled out and replaced should the threads get mangled.

With lots of other divers already in their collection Seiko most likely ditched the crown for the following reasons:
#1 cost savings and keeping the price down on the Seiko 5 Sports line
#2 100m is sufficient WR for a sports watch.
#3 it keeps this watch from competing with their divers and allows for some variety in the line up

When I first learned of the lack of a screw down crown I was pissed and swore I wouldn’t get one. Seiko must have known by adding lots of colors and unique duals and designs that their fans would only be able to resist for so long.

So you are gonna do the mods yourself rather than sending it off to Duarte or Yobokies or Dagaz?

Duarte did the mods on the ETA that has gone crazy, the one I posted about in the other thread.

When I first got it (from the guy who had the mods done) it was wonderful, only later did it go nutz on me.

Someone like Duarte (at NE Watch Works) can pressure test it and make sure it's not gonna leak like my 1960s Cornavin that I stuck in the dishwater (at my jewelers now getting cleaned and oiled as it is definitely not water resistant).

But if you do it all yourself, you are far braver (and waaaaaaay more skilled than me).

I anxiously await photos and results from the finished product.

Bob

I’m going to do it myself. I’ve been practicing crown stem removal on a few broken Seiko & Citizen autos I own as well as a fake/super clone Rolex Sea Dweller that has an asian ETA 2824-2 clone movement (it actually keeps infuriatingly good time) So far I’ve been able to get the crown stem on the Rolex out and reinstalled a few times with no problems. The fake Rolex is the only functional watch I’ve practiced on so far.

This is not a terribly difficult mod. The movement “should” come out complete and hopefully drop right into the Turtle. I might need to purchase a new movement holder but hopefully everything will fit.

I’ve fallen down the rabbit hole pretty deep when it comes to automatic watches. The way I see it if I break it the worst thing that has happened is I have learned what not to do. If that happens, and I hope it does not happen I’ll learn from it and keep on with this project.

A stealth turtle with the day date complication and amazingly good looks will likely end up in my heavy rotation once complete.

I was one of the first people on this forum to disassemble a Sig Pro fire control unit and attempt to put in a reduced power main spring (which I had to make on my own) to fine tune that already amazing trigger pull. I didn’t have any YouTube videos to go by with that project and had to basically figure it out on my own. This project should be just as fun and hopefully a little bit easier.

It would be pretty neat, especially for a dufus like me, if you were able to video your journey in moding this watch.

But that may be more trouble than it is worth to do.

Bob

Last time I made a watch video I was attempting to show how a quick adjust clasp worked and I ended up dropping my baby turtle onto a ceramic tiled table and got it all on video.

I’ll definitely post up pics of the process explaining the steps but I’m probably not a good person to make a video of such a mod. There are a lot of Seiko watch fans here so posting up pics of the process would probably be well received by the membership here.


I decided on a bezel and insert. The stealth turtle is going to get a sub style bezel and a ceramic insert identical to this.

Dang. If only Seiko had retained the screw down crown. I really like this watch. I almost feel bad that I’m going to be tearing into it.

I swapped it over to a mesh bracelet while I look for bezel inserts and bezels.




Seiko put display case backs on these sport watches.

The end result. I think it turned out great. With all the oddball variants Seiko makes I’m surprised they haven’t copied Steinhart who copied Rolex and made a blacked out diver like this yet. The sport 5 line seems to be where Seiko likes to dabble with their artistic creativity.

I left the bezel insert black and blue because it works great with the blue Seiko strap. I might change it out for a black ceramic bezel insert.


My next Seiko mod is going to attempt to look something like this. I already have a good portion of the parts acquired for the project!

Nice Hamilton!

Are you building a white-faced Seiko?