Which Daytona's have the improved 7750?

[Odyseus 1]

Everybody knows the fragile nature of the seconds at six A7750.

 

The older models had 5-6 extra gears.

 

However, the newer ones have three jewelled gears and are considered more reliable.

 

But does anyone know which Daytona rep's have the improved modified movement???

 

Cheers

 

John

[Cynikal.Mindset 1]

none that I know of...well last time I saw that there was no extra jewling in the daytonas or not where it was needed at least

[nathtommo_9 32]

http://www.p-cls.com/rlds00101-daytona-116520-ssss-white-stick-a7750-sec6-28800-p-12889.html

 

???

[SSTEEL 0]

Don't believe the TD spiel about the new 29J improved movement, its yet to be proved its anything but a normal A7750.

 

You can get the extra jewels added for €300 by modder next door, Domi.

[Frankt8242 1]

If you really feel the need to have a Daytona, you should consider the older "vintage" models with the seconds at 9(or was it 3..??)...

I used to have a HW model with a Seagull ST-19 that was quite reliable until I "got over" the Rolex fetish a few years ago...

[SSTEEL 0]

Vintage are Sec@9 Frank.

[Frankt8242 1]

Vintage are Sec@9 Frank.

That's what I thought, but I'm too lazy to bother looking it up!!...Thanx!!

[Wriggles 12]

Francisco did a teardown of the new mvmt over on RWI and theres no improvement, from what I remember they only drilled out some space in the plate where the extra gearing goes to reduce friction. Quick search on RWI should find it. On phone so too much of a pita for me to find it right now

[nathtommo_9 32]

http://www.repgeek.com/showthread.php?t=47094

 

[Frankt8242 1]

http://www.repgeek.c...ead.php?t=47094

Interesting necropost....

Lots of familiar old name there...Even Matusss....I thought he had scrubbed any reference to his existence from everywhere in "repdom" by now!!

[Odyseus 1]

I'll give the Daytona a miss then :(

[Wriggles 12]

Oops, as linked it was repgeek and not RWI as I said earlier.

 

You could always get one and send to Domi for modding, I believe he mods the 7750 with secs@6 by adding in the jewels that are supposedly added on the new versions, how effective it is I have no idea as so far haven't come across a thread with info from someone who's had the mod done.

[Cynikal.Mindset 1]

the mod alone costs more than the watch itself so you better damn well love the watch...but then still the modification of the movement isn't perfect

[Wriggles 12]

the mod alone costs more than the watch itself so you better damn well love the watch...but then still the modification of the movement isn't perfect

Ouch

[Stuvetjee 17]

Found this on rwi guys:

 

 

Hi:

 

I decided to buy a Daytona, given that the new movement was rated as 29j improved version. The watch arrived today and I decided to analyze it. I bought it from Joshua (Perfect Clones)

 

This is the watch I have received.

 

 

 

In the pictures, NEW is the supposed improved 29j mechanism, and OLD is a Daytona that I applied the graphite technique on 26 February 2008. I took then pictures of the process, and now I have taken very similar pictures to help the comparison.

 

The movement is removed from the case.

 

 

 

And hands and dial are removed.

 

 

 

Follows the first comparison. As seen on next picture, the transfer system is based on gears rotating on a plate, fastened with pins (green arrow) with no jewels. This is the same transfer system employed on the old model.

 

There is an improvement shown by the red arrow. This improvement consists of reducing the contact surface on the gear employing “skeleton” gears instead of “solid” gears.

 

 

 

After removing 3 screws, the top plate is removed. Follows pictures for each side of this plate. Next picture is top face.

 

As shown, there are 3 jewels in the top plate. However, these jewels were present in the old model. These jewels are located in the seconds, minute and hour outputs of the watch. Therefore, no improvement here.

 

 

 

The bottom face (next picture, red arrow) shows how some surface of the plate has been hollowed out. The objective is to reduce friction against the silver gear shown later (green arrow). This is one of the improvements, however, no more jewels are found here.

 

 

 

Next picture shows the silver gear (green arrow). This gear is rotating on the surface of the plate and, unfortunately, belongs to the seconds transfer. Therefore, it is always rotating. The only improvement for this gear was commented in the previous image. No new jewels.

 

As seen in next picture, the main improvement consists of reducing the contact surface of the gears employing skeleton gears, instead of solid ones.

 

 

 

In next picture the gears for seconds and minutes outputs are removed. The two red arrows shown that the minutes output has a jewel and no jewel for the hours. However, this was the previous configuration. Nothing new, no new jewels.

 

 

 

Now the seconds output gear is removed, the gear that is always running. Red arrow shows that there is not a new jewel. And a jewel here is much needed.

 

 

 

After removing 3 screws and removing the second plate the A77500 mechanism is visible. Nothing new here.

 

 

 

Two pictures follow for the second plate that we have just removed. The only difference, as commented before, is the use of skeleton gears. No new jewels. Follows top face.

 

 

 

Follows bottom face.

 

 

 

 

 

CONCLUSIONS.

 

There are no more jewels in this mechanism.

The improvement consists mainly in employing skeleton gears to reduce the rotating contact surface.

The transfer for minutes is better designed that the seconds transfer. The seconds are always running and the design is still very problematic.

Although there are improvements… definitively this is not a long life mechanism.

 

Thanks for reading,

 

Francisco.

 

[greg_r 83]

Domi does a worthwhile mod to the secs@6 'tona which much improves reliability, but the cost is significant and you're still left with the basic limitations of the A7750.

 

Honestly, much as I like the 'tona this is why I have a vintage 6263 (with ST19) and a Rotary quartz homage (which, incidentally, is gorgeous). Honestly, the secs@6 A7750 versions are too much of a headache.