thewightstuff Posted November 21, 2006 Report Share Posted November 21, 2006 was in the process of fitting a gen crown tube to an MBW submariner however the tube isnt for screwing into the hole at the moment. the hole seems to be the correct 3mm however it seems like the thread pitch isnt the required 0.3mm and it might be this thats causing the problems. has anyone any solutions regarding correcting the pitch, is it even possible or whats a workaround? anyone got a line on where to get 3mm x 0.3mm pitched taps. also FYI, ive got drawings for the various rolex crowns and the 7030 and 7020 are both definately 3mm x 0.3mm and not 0.25mm Link to comment Share on other sites More sharing options...
RWG Technical Posted November 21, 2006 Report Share Posted November 21, 2006 You need to run a tap through the hole for the new crown tube to fit... This post covers it all... How to install a crown and tube... Ofrei sells the taps. RG Link to comment Share on other sites More sharing options...
thewightstuff Posted November 21, 2006 Author Report Share Posted November 21, 2006 thanks The Zigmeister, id already looked at the threads but was somewhat unsure what the best approach was with the hole size being the same but the pitch being different. will running a tap through not just end up with a totally stripped case? i forcibly screwed the crown tube in and used loctite to hold and got it to work though the threads on the crown tube were rounded off in the process of going into the case. id be keen to think around better solutions for the next time i do it, if theres any suggestions or retapping will work ill just pull it out and stick in a new tube. Link to comment Share on other sites More sharing options...
RWG Technical Posted November 21, 2006 Report Share Posted November 21, 2006 I just run the tap through the case, and screw the new crown in... There is little else that can be done when the diamter is the same as the new one but the threads are a different pitch... My original post outlined a MBW and it was already 3mm but wrong pitch... all I did was run the tap through the case and it was fine. I do them all this way, as there is no other way to do it. RG Link to comment Share on other sites More sharing options...
ubiquitous Posted November 21, 2006 Report Share Posted November 21, 2006 I think the original pitch of the case threads is close, but just ever so slightly off from the pitch on the gen tube. So, if you run the tap, it's just cleaning up the case threads a bit. Link to comment Share on other sites More sharing options...
thewightstuff Posted November 21, 2006 Author Report Share Posted November 21, 2006 thanks guys, ubi, its close enough that you can get it to screw in but, atleast in this case it rounded the thread ends on the tube pretty seriously though it did hold fine etc. while once a crown tube is in, the only reason to remove is to replace so this rounding wouldnt really be an issue it isnt the way i usually like to work The Zigmeister, thanks for clearing that up, it doesnt mention running through the tap in the thread linked. i think ill get after buying one for future jobs. i was unsure whether it would just subtly adjust pitch and clean out our whether it would totally round out and leave a ruined case Link to comment Share on other sites More sharing options...
RWG Technical Posted November 21, 2006 Report Share Posted November 21, 2006 So far so good, of all the tubes I have installed, not one case has stripped as a result of the tap being passed over the original threads. I think the pitch difference is so subtle, that is doesn't make a big difference. Worth having a tap on hand if you intend to do a few more, and given that the rep crowns and tubes tend to strip after a while, it will pay for itself. RG Link to comment Share on other sites More sharing options...
thewightstuff Posted November 22, 2006 Author Report Share Posted November 22, 2006 thanks The Zigmeister, yeah im thinking that its worth the investment. had a look at ofrei however couldnt seem to see the correct tap. are the listings all by thread pitch and somehow this translates by default to a certain diameter by definition? im in the UK so im not sure ofrei is a viable source either. minimum orders and shipping kill most things though saying that. ive wanted to buy so much stuff over the last few months that ive ended up spending alot of time trying to source here in the UK when with hindsight i could have collected and got all at once. i guess i have a firefighting approach to watch tools and parts, in that when i need them its because ive hit a problem or something has broken rather than being prepared i take your point ref the generic crowns and tubes, they certainly seem softer than gen ones and the standard fare on the reps even worse. this was a generic crown tube for a trial and TBH im glad i only got the one Link to comment Share on other sites More sharing options...
RWG Technical Posted November 22, 2006 Report Share Posted November 22, 2006 I dont' buy anything from Ofrei, Bob Frei is a jerk to say the least... I am not sure of the pitch, I though it was 0.25mm at 3.00mm diameter, but you said it was 0.30mm pitch (I thought metric pitches ran in 0.25 increments). I am sure if you ask Cousins in UK they can tell you what one to use... RG Link to comment Share on other sites More sharing options...
thewightstuff Posted November 22, 2006 Author Report Share Posted November 22, 2006 (edited) The Zigmeister, if you were here right now i could kiss you,, though perhaps buy a you a beer may be better lol. ive been trying to find a watch source in the UK for what seems like an age and could never find the name of cousins. just ordered a whole load of parts from them already lol. Edited November 22, 2006 by thewightstuff Link to comment Share on other sites More sharing options...
RWG Technical Posted November 22, 2006 Report Share Posted November 22, 2006 ziggy, if you were here right now i could kiss you, Well a year ago, after being a single dad for a number of years, I may have taken you up on the offer...but now I have a lady friend....so I am taken so to speak... though perhaps buy a you a beer may be better lol. ive been trying to find a watch source in the UK for what seems like an age and could never find the name of cousins. just ordered a whole load of parts from them already lol. Thanks for the pictures of the crowns and the dimensions etc...good info to have on hand. The difference between 0.25 and 0.30mm on my calipers while trying to measure the pitch is too small to note...and I had never seen an odd pitch so even if I had measured 0.30mm I would have assumed I was measuring it wrong... Great info, I have printed these out for reference to add to my library. RG Link to comment Share on other sites More sharing options...
thewightstuff Posted November 22, 2006 Author Report Share Posted November 22, 2006 haha, that gave me a good old laugh. glad to hear that you are more than willing to take the beer only. no probs ref the drawings, glad they are of interest. i thought taps were stepped 0.25mm too. i had no joy finding an 0.3mm tap but did get an 0.35mm one in 3mm!!!!!! that pretty much throws out any logic at all though apparently its whats knows as fine thread amongst machinests (though im not one so it could be BS) im hoping that like you found with an 0.25mm pitch, its negligable difference and works well. Link to comment Share on other sites More sharing options...
vaccum Posted November 22, 2006 Report Share Posted November 22, 2006 More info on the crowns vaccum Link to comment Share on other sites More sharing options...
thewightstuff Posted November 22, 2006 Author Report Share Posted November 22, 2006 nice addition, id not seen those pages before. the one with the top view of the crowns is excellent. didnt realise they had different ball sizes relating to material of construction Link to comment Share on other sites More sharing options...
vaccum Posted November 22, 2006 Report Share Posted November 22, 2006 Here is the translation acero=steel oro amarillo=yellow gold oro blanco=white gold platino=platinum Cheers, vaccum Link to comment Share on other sites More sharing options...
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