JF Daytona Vs Gen

[2671]

I have made a few shots comparing the JF new 116520 to my Gen.  It is amazingly close to the real deal.  The crown guard reshaping suggest by a few fellas is a must compare to other minor discrepancies.  The rehaut sanding and RRR removing is good if you have the skill to DIY due to wrong font and satin finish.  The crown sits a bit low I would say about 1.0mm compared to gen, it don't look that bad in reality but it's there when you know what to look for.  The bezel font and thickness seem fine to me, switching to 7750 bezel is a bit overdosed.  The gen tips the scale at 12.7 vs the rep 12.85 with the same protective film (from JF factory) stuck to caseback, to me it's dead on.  For those who still anal about this can either shave the crystal gasket or the case back down 0.1mm...  What amazes me is the overall fit and finish, it really screams gen, unlike Noob factory the new JFs don't have sharp edges anywhere on the watch head, it's a huge step forward in the rep world.  The SEL is rubbish while the clasp is 90% on the outside 50% inside, quality wise.  That said I have a BP band ordered from a friend of mine who lives in GZ, yet to receive and I'll post an update when it gets in.  I'll freeze the 3 & 9 Subdials when I have time to fiddle with it, it bothers me a bit for daily reset and I dun wanna pay for new crown and tube set every few months down the road...  Enjoy the pics!

 

 

 

Edited May 1, 2016 by 2671

[TheSociety]

Subscribed! I just got my JF black dial 23j and my white dial will come

Soon! Your shots are awesome for comparison. Can't wait to hear your update on the BP bracelet

[2671]

Congratulations!  From what I have seen, the white dial has a proper space between Subdial 6 and 6 o'clock marker, so more accurate.

My friend told me the BP band is a bit flimsy compared to new Noob Sub band, anyways let's see... 

[IAN2109]

Excuse my ignorance but whats JF?!

[2671]

J12 Factory, made their first bucket of gold by repping the Chanel Ceramics. 

[IAN2109]

Thanks how do you orden from this factory?

[Sogeha]

Thank you for an excellent review. This rep looks good and a possible candidate for a franken.

[2671]

As memory serves, I've read on Repgeek that someone has started a franken WIP.  Gen dial on gen 4130 fits in case but leaves a gap below the rehaut, crown stem won't line up since crown hole being too low.  I bet gen dial won't fit NN3836 movement without cutting dial feet. 

22 minutes ago, IAN2109 said:

Thanks how do you orden from this factory?

Perform a search, available at few TDs

[Sogeha]

Thanks, found it. Link to save anyone else searching:

http://www.repgeek.com/showthread.php?266371-New-Project-Super-Franken-Daytona-116520&highlight=116520

[automatico]

Here is an earlier thread about what may be the same watch (I am not sure) and it has a good pic of a white dial model (post number 14).

https://rwg.cc/topic/182274-best-daytona-rep-on-the-market-today

The white dial watch that I froze the dials on is a bit different...1mm thicker case, thinner crown, has a DG movement, and still runs fine (in warm weather anyway). I have both types of this model...bracelet and leather strap but they appear to be identical from the front side to the one in these pics except for the hoods on strap models. 

"What amazes me is the overall fit and finish, it really screams gen..."

Me too, I was impressed with the overall case fit/finish, dials etc...everything except the plastic movement spacer. I would have to cut a groove around the inside of the case for clamps and make a brass spacer to get rid of the plastic spacer but it is really OK the way it is. Since I would not use the chronograph much at all, this type of movement suits me fine and should give less trouble than the 'Old Reliable' A7750 s@6. I froze the center timing sweep second hand and hands on the sub dials at 3 and 9. It originally came with the center sweep timing hand and second hand at 6 running all the time and the dials at 3 and 9 marked same as genuine but were day and date so I took it apart and froze them. There is a post somewhere telling how I did it but I do not have a link to it.

[2671]

Thanks automatico for sharing, #14 23J white dial is breathtaking, nothing beats gen crystal!  I am sure it's the same movement in ours.  You also had the RRR engraving removed and sanded rehaut, it really brings it to the next level.  Frankly I am not a big fan of the engraving gen or rep, plain jane always looks better to me.

This new JF 116520 does not have plastic movement spacer but a metal one.  The lug engravings say Steel & 18K Yellow Gold and 116523, I'd expect a 2 tone model to follow.  I also have this old Canal Street rep given by a customer laying around, I bet that's the same one you had worked on in your thread.

I'll post an update when the new BP band comes in and time to work on the new Nan Ning 3836 (I believe it is) movement.  Here's a few pics for reference.

P.S. For those who are not familiar with this movement.  The one with spring bars is JF's new 116520 with NN3836 movement.  The one on the right with white plastic holder is the DG 21J.  If anybody has taken one of these apart please write a review, thank you.

[997 s]

Great review

[2671]

It's time for a litte recap and update on this project.  To disable the day date subdials on this JF 116520 Daytona, all you need to do is to remove TWO wheels as shown below.  If you know what your doing and don't have a fainted heart, it's a great weekend DIY project for you.

Removing the movement from the case is pretty straightforward and I'll skip a thousand words.  Dial off, first thing you'll notice is a plate or bridge, being held down by 11 screws!  Carefully remove them and get the plate out of your way.  Exposed are the day and date wheels, take off the two wheels as shown in my pics.  You can also leave the levers there since they don't mean nothing now.  A litte dab of epoxy glue on the two wheels to make sure they don't spin when you put the subdial hands back on.  Voila, mission completed!

Since the movement was out, I spent sometime to sand off the rehaut engraving to a period-correct 2000-2005 year model and shaved off a chunk of metal (from the top) to thin out the thick rehaut.  Reshaping the crown guards and polish the SEL on this JF band to my liking.  In fact, this band is not that bad compared to the BP band I acquired from my GZ friend, nothing a bit of proper sanding and polish can't fix.  The awkward SEL curve to some don't bother me too much cos I have small wrists.  The BP band I got was $50 but quality wise don't even come close to any late model TC Sub band, so forget it...

 

 

Edited May 19, 2016 by 2671
Double post of pics

[ap2013]

great review thank you for sharing

[2671]

9 hours ago, ap2013 said:

great review thank you for sharing

Your welcome, that's what we are here for

[hologramet]

 

On 2016-05-21 at 5:32 AM, 2671 said:

Your welcome, that's what we are here for

Hmmm..

I have a weird request. You don't happen to know the size of the 23J-mvmt?

Because an acquiantance of mine happens to have all gen parts for a 6-digit Daytona, except for the midcase.

[2671]

20 hours ago, hologramet said:

 

Hmmm..

I have a weird request. You don't happen to know the size of the 23J-mvmt?

Because an acquiantance of mine happens to have all gen parts for a 6-digit Daytona, except for the midcase.

As we speak, this JF midcase will not house a gen 4130 as per this thread: http://www.repgeek.com/showthread.php?266371-New-Project-Super-Franken-Daytona-116520

However, there may still be a chance to get them to work by moving the crown position up, shave some metal inside the case and shorten the pusher rods.  I will dig into that when I have time.

 

[hologramet]

On 2016-05-24 at 3:26 AM, 2671 said:

As we speak, this JF midcase will not house a gen 4130 as per this thread: http://www.repgeek.com/showthread.php?266371-New-Project-Super-Franken-Daytona-116520

However, there may still be a chance to get them to work by moving the crown position up, shave some metal inside the case and shorten the pusher rods.  I will dig into that when I have time.

 

I'm checking with Yuki and Phong regarding this. I know Phong can do it, I don't know what he'll charge.. But it can't be astronomic compared to the remaining parts.

It's a shame 2 pcs 4130's, 1 pc 4030 ... just laying there NOS... and dials, hands, pushers, crowns...

[2671]

I can do it but it's a matter of time.  Friend of mine can do the machining and cold welding (moving crown position anywhere you like).  I am planning to turn in mine to see if feasible as well.  I'll take some measurement next time at the bench.

[Sogeha]

It would be awesome to be able to take this rep and make it able to fit a gen movement and fix the crown height. I just had a quick scan on the Internet and 116520's seem to be available at around USD10,000. I think the movement is 3000? So I guess it depends what the case work costs as to how much sense the project makes. There are a lot of rep cases that would benefit greatly from a little welding and redrilling. Watching with great interest.

[2671]

9 hours ago, Sogeha said:

It would be awesome to be able to take this rep and make it able to fit a gen movement and fix the crown height. I just had a quick scan on the Internet and 116520's seem to be available at around USD10,000. I think the movement is 3000? So I guess it depends what the case work costs as to how much sense the project makes. There are a lot of rep cases that would benefit greatly from a little welding and redrilling. Watching with great interest.

Either using cold (for thicker metal) or laser (thinner) weld to avoid case distortion.  The exact recipe of the metal has to be found and tested (i.e. 316F or L) otherwise the filled hole will leave a surface gap between the old and new metal.  Finding the right guy plus the time to master the technique could be pricey, the probem with rep cases is they are made of different type of SS...  Also, the welded localized area as know as the "heat-affected zone" is extremely hard to drill through.  Now my guy is working on something that combines both welding techniques to see if it can apply to our hobby.

[hologramet]

It all depends if feasible or not, Gen Daytona parts are quite expensive, and I for one would not buy all the items for a complete Franken. Maybe the parts have already existed for a long time, somewhere on a shelf, unopened, knowing that Rolex never ever makes a replacement case unless old (non existing) is sent in first

The welding techniques discussed are most interesting, what is the ETA for a prototype? Becquse Phong is not especially quick at answering.

Some measurement of the mvmt would be awesome!

[2671]

On 2016/5/28 at 0:35 PM, hologramet said:

It all depends if feasible or not, Gen Daytona parts are quite expensive, and I for one would not buy all the items for a complete Franken. Maybe the parts have already existed for a long time, somewhere on a shelf, unopened, knowing that Rolex never ever makes a replacement case unless old (non existing) is sent in first

The welding techniques discussed are most interesting, what is the ETA for a prototype? Becquse Phong is not especially quick at answering.

Some measurement of the mvmt would be awesome!

Due to my heavy schedules, I can't show up at the machine shop but talk on the phone.  All I could do was to send him a few old experimental cases until I hear something solid.  Anyhow, the latest update was something like eccentric tubing...

These shots are from my bench this morning, cheers!

Dial feet are slightly off comparing to gen pic captured on the bay.

Gen 4130 movement owners pls chime in for the same, that'll be great help.

[2671]

Few requests for the mods, so I figured to take better shots for you all.  I had all the subdial related levers/rods removed this time for an even cleaner look.  Instead of epoxy gluing the wheels to the main bridge, I had it glued to the top thin metal plate.  They come right off with the top plate when next service is due.  Here ya go:

 

[rolojack]

Great review !!! Thanks for sharing. Are the pushers screwed in the case like gens? Or are they simply forced in like the vintage style reps of the cartel? thanks !