Tube questions

[theapexseal]

I an currently building a vintage 5513 project starting off with a Josh watch, and had a few questions about fitting the gen tube into the case.

I bought "Gen like" tubes from Yuki for the project, and will obviously need to re- tap the case threads. Does anyone know the exact tap dimentions to use. I read somewhere that it might be 3mm x .25 but it was uncomfirmed. Would like to be sure before I order a new tap set.

Also should I set the tube with GS hypo cement or epoxy or something else to make it water proof?

I will also need to grind a chamfer into the case at the top of the tube hole to accomodate for the chamfer on the tube for a good fit correct?

Thanks in advance guys!

[freddy333]

Does anyone know the exact tap dimentions to use. I read somewhere that it might be 3mm x .25 but it was uncomfirmed.

No idea of the tap dimensions, but I use these to tap tube & pusher holes (I cannot recall which of the 2 is for which hole)

Also should I set the tube with GS hypo cement or epoxy or something else to make it water proof?

I use GS. If you are absolutely certain you will never need to remove the tube, you can use epoxy. But GS does a good job & leaves the tube removable.

I will also need to grind a chamfer into the case at the top of the tube hole to accomodate for the chamfer on the tube for a good fit correct?

Depends on the existing hole. Test fit & chamfer if needed.

[praetor]

I thought it was m3x0.35 (pretty hard to find)

I just use loctite blue to make the tube waterproof on mine.

[theapexseal]

Yeah i just saw those taps on cousins site, and will probably go ahead and order if I cant get anything local. Just dreading the down time in shipping!

As a seperate question should I use GS around the crystal as well before pressing it in? Im completelly perplexed as to how these things can be watertight at all with just a press in crystal and retainer and no gaskets! Am I missing something here? the Crystal is just pressed into the case with the retainer around it right? This is accurate to the gen 5513 design?

Thanks for the help guys!

[alligoat]

Yes, the correct tap is 3.0mm x .35. Jules Borel and Ofrei also carry them. You can find them at tool supply houses also for less, but the .35mm thread pitch is somewhat of an oddball.

As a seperate question should I use GS around the crystal as well before pressing it in? Im completelly perplexed as to how these things can be watertight at all with just a press in crystal and retainer and no gaskets! Am I missing something here? the Crystal is just pressed into the case with the retainer around it right? This is accurate to the gen 5513 design?

Thanks for the help guys!

You could use the silicone grease or the G-S Hypo cement. The original construction was a tight compression fit. Around the 70's Rolex added a rubber gasket under the compression ring. Don't know if they use silicone or not, but probably not G-S Hypo cement.

[Ronin]

+1 on the 3.0mm x .35 TAP.

The recommended tube sealer should be LOCTITE #290

Loctite 290 is great because unlike GS it will not unthread by mistake. It can be easily removed by applying about 1 minute of heat from a soldering iron to heat it up.

I use #290 on all my builds for securing:

Crown to Stem

Tube to Case

Ohhh, as far as countersinking the tube / chamfering. If you are using a GEN crown, the little bit of stand-off you get by NOT countersinking actually adds a look of authenticity to the crown by standing off the case a bit, and the illusion the CG's are smaller.

Good luck

[Logan]

Just keep in mind that Rolex do make over size threaded tubes, and we presume custom taps to match. They are used for repairs where the threads are damaged. Quite a few over size threaded tubes were sold online a few years back and still pop up front time to time.

The regular thread is 2.98mm, the over size is 3.02mm from memory.