Hi everyone! Recently I acquired my first Rolex, a simple manual wind Precision from 1966. The case size is atypically large for a Precision at 36 mm. As it's not a hugely valuable watch and I intend on keeping it for many decades, I'd like to swap out the crystal for a sapphire and potentially change the case back to an exhibition back, too. Would anyone who owns the same reference be able to confirm the crystal diameter? My online research indicates either 29.3 or 29.5 millimetres but I'm uncertain which one. I'd also like to know if the caseback would be the same size as the 36 mm Explorer?

Thank you to anyone who can provide an answer or two!

 

Far from an expert on anything Rolex but I believe cases are designed either for an acrylic crystal or sapphire crystal, it's not a matter of just swapping one for another.

 

Thank you for the advice! I assumed that the sheer number of aftermarket domed sapphire crystals for Rolex models might indicate that at least some of them work alright. But if there's a compromise in the fit and watertightness, it's not worthwhile. For now, I've ordered an aftermarket caseback, it was aimed at the Explorer and Datejust models which are the same diameter as the 6424. Might add a bit of thickness or it might not work at all, but it's a cheap experiment.

 

could you provide a picture of the Rolex...just to have an idea of what you have

 

Just a fairly standard 6424! From what I've seen, most of the arrowhead/sharktooth dials came with dauphine hands, but the serial dates this one to around 1966 so I don't think the sword hands are out of place. I've given up on the idea of a sapphire crystal now I understand how they are seated in the case. I'd still like to add an exhibition caseback though, if it's possible. That said, can anyone confirm the back's thread diameter on theirs? I don't have the correct tool to open it and measure for myself.

 

thanks for posting the pic. seems like that you have a nice looking Precision there. probably the best thing to do to enhance the beauty of this Rolex, change the strap with a nicer leather one , different color and not necessarily expensive. It will change drastically the look of your Rolex. the strap that you have now, basically kills the beauty of the watch. I don't know where you can get an exhibition back for this Rolex, but I don't think it would be appropriate.
but on the other hand....we all have different test and opinions !!!

 

The strap stays for now, sorry. my skin breaks down leather straps like nobody's business, I'm lucky if I get a year out of one and six to nine months is more typical. I do have an oyster bracelet on order which I will swap to so the strap won't be on it forever.

 

This bracelet arrived today - cosmetically it's similar to the riveted bracelets shown in the catalogue published the same year my watch was made, however the links are solid steel and the outside part is just cosmetic. A quick adjustment to the end links with some rubber coated pliers and it fits like a glove. And no, it doesn't have a Rolex clasp, I'd rather not pretend it's something it's not.

I haven't seen many 6424's here, especially with the silver dial and arrowhead markers. Is it considered uncommon?

 

hello, I also have a Rolex 6424 and am desperately looking for a steel bracelet to match this watch. unfortunate the bracelet with the endlinks 75 is very rare.
where can I found your bracelet ?
Thank you.

 

You should be able to fit head links for a similar vintage datejust on it. Even more so if you go with a jubilee. I think the #55 jubilee head links are a good fit.

 

6424 does not have lug holes so requires end links to have access to spring bars like the end link 75.

 

Watches with sapphire crystals and display backs should be easy to find. Converting your Rolex to sapphire crystal and display back? Keep us posted regarding your progress in doing that.

 

You might have to get creative and notch the headlinks.

 

These oversized precisions seem to be prevalent in the tropics and SEA. I would check with HK sources for the #75 head links or complete bracelet but it's gonna be difficult to track a lone bracelet or parts down I think. I would notch a common set and be done with it.

Despite the previous remark from another "contributor" in this thread and sapphire-wise there are "kits" to install them on 16XX series datejusts which have similar size crystals as yours but I wouldn't suggest it. There is also aftermarket suppliers for see thru case backs as well. However your reference is fairly collectible so why monkey the thing up?

 

hello Tropicconnie, could you tell me the brand of your steel bracelet adaptable to the 6424?
Thanks

 

Apologies for responding late! The bracelet was from eBay. Search for "20 mm rivet bracelet" and you'll find several options. Presently it's on a sporty vintage rally strap and running +3 on the wrist per day.