Any interest in the proper tap...

[Guest avitt]

It's a generally accepted fact that the pushers that come on DW vintage Daytona case sets are of mediocre quality. The aftermarket pushers sold by Ofrei and Cousins are much more like genuine in construction, and are a big step up in quality. However, there is a problem...The aftermarket pushers have finer thread pitch than the original DW's. Aftermarkets have 5 threads per mm, while DW's have 4 threads per mm. This doesn't sound like much of a difference, but it means that the Ofrei/Cousins pushers cannot be screwed into the case (and many a pusher has been trashed by trying to force them in )

The common taps that are sold for Rolex cases are correct for the DW pushers, and all of the 2.5mm Rolex tubes, but they are not correct for the aftermarket pushers.

Well, after a fairly exhaustive search, I've finally found a source for the correctly sized tap. The taps are M41 HSS cobalt steel, and are designed for cutting and cleaning through hole threads in hard materials like stainless steel. The problem now is that the tool must be custom made...And for a single piece, the price is ridiculous. But it's a little bit less ridiculous if I buy 3 pieces.

So here's my question: Are any of you modders out there interested in buying one of these taps? If I can get 2 more people to commit, the price will be about $80 each. Please let me know if you're interested.

(Disclaimer...I have not yet performed this mod, and cannot guarantee that it will work. My plan is to run the tap through the pusher hole, using cutting fluid, in an attempt to re-cut through the existing threads. I will then use thread sealant to assure that the union is water tight. Again, I cannot promise that this will work. Proceed as your own peril.)

[vlaletom]

That could be good news !

I think this would work, since i have been able to force aftermarket pusher to the case, it is very pobable that runing a corectly sized tap would let enough grip fro the pushe to screw in firmly, but this time leaving the ability to be unscrewed.

would the price go down even further if you get more then 3 ? like for example 10 ?

it is very probable more then 3 ppl would be intersted.

Especially if there is still a shortage of DW style pusher.

[Guest avitt]

That could be good news !

I think this would work, since i have been able to force aftermarket pusher to the case, it is very pobable that runing a corectly sized tap would let enough grip fro the pushe to screw in firmly, but this time leaving the ability to be unscrewed.

would the price go down even further if you get more then 3 ? like for example 10 ?

it is very probable more then 3 ppl would be intersted.

Especially if there is still a shortage of DW style pusher.

Yes, the price will go down further with more volume. I'll just leave this up for the weekend, to guage the interest, count them up, and we'll go from there.

[freddy333]

I think the threading problem is due more to case-to-case variation (lack of QC) than to an inherent thread pitch mis-match between the pushers & basic case design. Out of the dozen or so DW cases I have worked on, I only had a Ofrei pusher-fitting problem with 1 of them, and the pushers that came with that case did not fit either (they kept falling out of the case because the holes were cut a fraction of a mm too large - I think I posted micrometer pics of the holes in 1 of my Daytona construction journals). All the other pushers fit perfectly after the case was tapped with the Rolex tap.

[Guest avitt]

You know that I have the greatest respect for your opinions, freddy333...But in this case, my experience has been 100% opposite from yours. I have mangled more than one expensive pusher, by trying to force them into holes with mismatching threads (and yes, I do always retap the thread on all DW Daytona cases).

A male .2mm metric thread will not fit into a female .25mm metric thread...You can turn it about 1/2 turn before things start to go haywire.

Here is the empirical evidence:

This is picture of a DW pusher, set next to my micrometer, which has been set to exactly 1.0 mm:

You can see clearly that there are 4 threads per mm.

This corresponds with the same thread pitch on the tap:

Now, compare this with the 5 threads per mm found on the Ofrei pusher:

Of course my knowledge in these matters isn't complete, but I do have a bit of experience

[alligoat]

I'm interested, avitt. Someday I'll get around to building my V72 6238 and I'm planning on using a DW case. I just have to finish one more 16610 (w/ a relumed Comex dial) first, or at least that's my story at the present time.

[vlaletom]

for my little experience compared to yours i can confirm that fot the 3 DW that i have now swapped from DW pusher to cousin's i had to use my dirty technic of "forcing" the cousin's, while DW's where an easy fit.

I do think they are not shearing the same thread pitch.

Unfortunately i am not a gen daytona owner

But i gess that ofrei's and such are the exact gen spec and that rolex use different tools for pusher than for the crown tube, while rep maker just avoid to use different machinery.

[Guest avitt]

But i gess that ofrei's and such are the exact gen spec and that rolex use different tools for pusher than for the crown tube, while rep maker just avoid to use different machinery.

I suspect that you're right, vlaletom. That only leaves one mystery: If it's a standard Rolex tool, why is the proper tap so difficult to find?

[db1]

avitt - PM sent