RWG Technical Posted July 9, 2008 Report Share Posted July 9, 2008 I cut the following new threads on some stems to test out my new Dies. I placed each stem in my lathe, cut the existing threads off and trimmed the stem to the end diameter I was aiming for. Then I ran my Die over the shaft while the stem was still in the collet. I think the results are great. First up is a ETA 6497 1.20 mm stem that was cut down to 0.90 mm, of course you know what this means for PAM owners... Then I had to make a Cortbert 616 stem which measures out at 1.50 mm and cut it down to 1.20 mm to fit the crown. Thanks for looking. RG Quote Link to comment Share on other sites More sharing options...
HauteHippie Posted July 9, 2008 Report Share Posted July 9, 2008 Wow, great project there, R & R. Very cool stuff! Quote Link to comment Share on other sites More sharing options...
vlydog Posted July 10, 2008 Report Share Posted July 10, 2008 Top shelf results as always RG! Quote Link to comment Share on other sites More sharing options...
HauteHippie Posted July 10, 2008 Report Share Posted July 10, 2008 The new threads turned out great. Running the shaft through the die while still on the collet is a great way to do it. At what RPM setting were you running the lathe though, or did you just spin the shaft by hand? Quote Link to comment Share on other sites More sharing options...
RWG Technical Posted July 10, 2008 Author Report Share Posted July 10, 2008 I turned it very slowly and carefully by hand. I am really pleased with the quality of the threads. RG Quote Link to comment Share on other sites More sharing options...
gianton Posted July 10, 2008 Report Share Posted July 10, 2008 Great work well done! Quote Link to comment Share on other sites More sharing options...
HauteHippie Posted July 10, 2008 Report Share Posted July 10, 2008 I turned it very slowly and carefully by hand. I am really pleased with the quality of the threads. RG OK. Yea, I agree, the threads are very clean. Quote Link to comment Share on other sites More sharing options...
Guest carlsbadrolex Posted July 10, 2008 Report Share Posted July 10, 2008 I had to thread a 2" diameter pipe last week and couldn't get the threads to look that good. I guess this is what steady hands and good eye sight can do for you! Very nice work! Quote Link to comment Share on other sites More sharing options...
ubiquitous Posted July 10, 2008 Report Share Posted July 10, 2008 Looking good! I'm quite excited over this, but I just can't put my finger on why... Oh, wait! I know! It's cause I think this little guy could use one of those Tap10 6497 stems! Quote Link to comment Share on other sites More sharing options...
FxrAndy Posted July 10, 2008 Report Share Posted July 10, 2008 Any one know where we can get gen crowns from???? Unckle Jay where are you????? Quote Link to comment Share on other sites More sharing options...
scoobs1971 Posted July 10, 2008 Report Share Posted July 10, 2008 Very interesting project Thnx R&R! Quote Link to comment Share on other sites More sharing options...
stilty Posted July 10, 2008 Report Share Posted July 10, 2008 Wow nice work! Very impressive. I know that when watchmakers make new stems, they cut and finish the stem, then harden it later. That is impressive that you were able to cut the hardened steel! Off Topic: Isn't making a stem from scratch one of the requirements to receive your WOSTEP certification? If I had 30K and two years of free time, I would love to get a WOSTEP certificate. Quote Link to comment Share on other sites More sharing options...
andreww Posted July 10, 2008 Report Share Posted July 10, 2008 Very impressive Zig. Always amazes me at the amount of precision that can be obtained on such small pieces. Quote Link to comment Share on other sites More sharing options...
slai Posted July 10, 2008 Report Share Posted July 10, 2008 Wow! Quote Link to comment Share on other sites More sharing options...
DemonSlayer Posted July 10, 2008 Report Share Posted July 10, 2008 Very nice work The Zigmeister, you never fail to impress Quote Link to comment Share on other sites More sharing options...
Logan Posted July 10, 2008 Report Share Posted July 10, 2008 Very nice work. I guess I'll have to buy a watchmakers lathe one day.. just to play.. A question for ubiquitous.. where did the crown tube in your picture come from? Is it genuine? I have a couple of gen crowns but they don't really work with the rep tubes as you end up with doubled up o-rings. Quote Link to comment Share on other sites More sharing options...
owdeguy Posted July 11, 2008 Report Share Posted July 11, 2008 Looks great. I'd be interested in getting some of those if you make them available. I'd like to use your lume services too when you have some time. Quote Link to comment Share on other sites More sharing options...
Watchmeister Posted July 11, 2008 Report Share Posted July 11, 2008 Ziggy- Those stems are a work of art. Can't wait to see them on their respective watches. Logan- The case tube is from a Jimmy case. It is identical to the case tube on a gen case. Fxrandy- Knowing this project was forthcoming and it would allow for the use of the gen automatic crowns on handwinds I did hold back a few crowns for this purpose. The remaining crowns will be offered with stems and possibly case tubes. No worries though as I will make a general announcement when they are ready for prime time. Quote Link to comment Share on other sites More sharing options...
bwhitesox Posted July 11, 2008 Report Share Posted July 11, 2008 Very nice The Zigmeister...Amazing job as always. Quote Link to comment Share on other sites More sharing options...
ubiquitous Posted July 11, 2008 Report Share Posted July 11, 2008 Very nice work. I guess I'll have to buy a watchmakers lathe one day.. just to play.. A question for ubiquitous.. where did the crown tube in your picture come from? Is it genuine? I have a couple of gen crowns but they don't really work with the rep tubes as you end up with doubled up o-rings. Logan, As kruzer mentioned, this tube is from a Jimmy case (pictured in the background). The gen crown just slides right in and engages with a nice reassuring click. Quote Link to comment Share on other sites More sharing options...
Shundi Posted July 11, 2008 Report Share Posted July 11, 2008 Ingenious ! Quote Link to comment Share on other sites More sharing options...
cskent69 Posted July 11, 2008 Report Share Posted July 11, 2008 I cut the following new threads on some stems to test out my new Dies. I placed each stem in my lathe, cut the existing threads off and trimmed the stem to the end diameter I was aiming for. Then I ran my Die over the shaft while the stem was still in the collet. I think the results are great. First up is a ETA 6497 1.20 mm stem that was cut down to 0.90 mm, of course you know what this means for PAM owners... Actually The Zigmeister - I don't know what that means. Could you tell me? A little out of my league here. Quote Link to comment Share on other sites More sharing options...
POTR Posted July 11, 2008 Report Share Posted July 11, 2008 Lovely work! Quote Link to comment Share on other sites More sharing options...
Watchmeister Posted July 11, 2008 Report Share Posted July 11, 2008 CSK- Since I am a layman as well I will take a shot and Ziggy can correct me if I got it wrong. As you probably know each stem has two sides. One side slides into the movement and allows you to wind and set the movement. The other side screws into the crown. The problem has always been that there are some movements which take a larger size stem going into the movement such that the side that screws into the crown is to wide for the crown. So what he is doing is trimming the stem to the right length if necessary and then thinning out the threaded side and rethreading it so it will fit into a smaller hole (the crown). The real life examples above are: Cortebert movements often take a 1.5 mm stem. Our usual hand wind crowns take a 1.2 mm stem. So unless you can thin down and rethread the crown side you can't use our normal crowns. 1.2 to 0.9mm - Standard Unitas movements take a 1.2 mm stem. However most of the gen crowns that we bought through our group buy were originally for automatics which have a threaded hole of 0.9mm. Often this can be remedied if using a smaller movement by buying an adapter which screws onto the 1.2mm side and leaves you with a new 0.9 mm threaded end. However in the case of the Unitas movements they are so big that there is no room in the case for an adapter. Ergo you need the revised stem in order to use SS gen crowns that folks bought with handwind movements. Quote Link to comment Share on other sites More sharing options...
RWG Technical Posted July 11, 2008 Author Report Share Posted July 11, 2008 Kruzer got it right. The "Dies" which I forgot to take a picture of, are about the size of your pinky finger nail, and they are designed to cut new threads on a shaft. The big issue is that as stilty mentioned, these stems are already hardened and it's quite a challenge to cut threads that small on a hardened shaft. Keep in mind that the 0.90mm one is less than 1 millimeter in diameter, were talking really small parts to work with. At $60 per Die, it's not cheap to get the tooling, I just hope the Dies last a long time or that I don't break them like I did with my rollie crown tube tap... RG Quote Link to comment Share on other sites More sharing options...
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