Every once in a while, your mechanical or quartz clock is going to have an issue with a screw-down crown that no longer rightens up on the case.
This happens for several reasons, but, with my experience, the main reasons are as follows…
- Gaskets get worn out.
- Threads on crown become dirty.
- Threads on post become dirty.
- Someone over tightened the crown, and damaged the threads.
For this example, I’me using a vintage Rolex President model that the customer, over the years, tightened up the threads a bit too much, while at the same time, requiring a new crown.
Watch the Video Here!
How is the crown made?
Understanding the makeup of a crown is important. In our video above, you’ll notice that the crown itself, if you looked closing is 18k, over stainless. These materials are bonded together during production.
A Spring Post head is added to the crown, and pressure fit into the crown head.
A inner Crown Gasket, which is usually flat, is then put into the crown.
Finally, the stem is added to the crown, measured and cut to proper length.
This watch, has a threaded crown, and requires the post on the watch case to have the same thread angle, so don’t try and use mixed or matched crowns you are unfamiliar with, until you made sure they match properly.
Click on images to purchase!
Checking the crown and case post
If, as in this example, the inner crown threads have become stripped by age or abuse, then the next thing, is to check the threaded post on the case. Make sure that the threads are in good condition. The post, which screws into the case is stainless steel. It is much more durable then is the inner threads of the crown, and usually the last part of this assembly to become damaged, but it is necessary to check for any.
Make sure that you examin these threads under magnification. That is important, as to determin whether or not you can save any of these pieces!
If, like this watch, the case post is fine, then it’s time to examine the crown. On this 18k gold grown, all the lower threads have been damaged.
I’ve seen this watch a couple of times over the last six months. The customer has a quote for a new crown, however, he doesn’t want to invest in the crown because of its cost! $750.00. (don’t forget, this is my retail price, not the cost).
Can we save the crown?
Sometimes I can save the crown, sometimes not. I always recommend that in time, you will need a new crown, new gaskets and a water test to make sure that the watch remains water resistant.
The repair I’m performing here, is a quick fix, and will last the customer about a year or perhaps, slightly longer.
The threads on the crown, close to the opening of the crown are stripped. This doesn’t allow the crown to grip the threads of the post, and won’t tighten any longer.
The solution to this is to remove the inner gasket of the crown, the flat gasket, and to cut down the crown so that the better threads on the inner part, make good contact with the watch case post.
Please, remember that the only reason I’m doing this is for two reasons…
First, the customer does not wish to spend the money on a new crown at this time, and wants to wait until spring, (six months from now).
Second, the crown is ruined, and will be disposed up anyway, so making this change is not going to de-value the watch in any case.
However, the disadvantage, is that the watch will lose one gasket, which increases the chance of water infiltration.
How to file down the crown
If you don’t have a watchmaker’s lathe, or a small machine lathe, then you can use a good set of files, with smooth sides. Smooth sided files, will not cause damage to the step, or crown post.
With my lathe, I was able to take enough material off the crown, about 1/4 of a mm each time, and then test it until I was happy with the results of the work.
With files, it will take a bit longer, and require just as much cleaning, so be prepared, and do not rush. Just a little bit at a time.
The result that I’m looking for is that the crown should fit onto the case, and have at least one full turn on the threads of the case post, thus holding it in place!
Making sure you retain water resistance!
As I’ve stated several times, this fix is for temporary repairs only!
If you want to make sure that your Rolex remains water proof, dive friendly, and ready to wear any time, and any place, make sure you follow the proper repairs for this…
Here are the steps you need to take to make sure that your Rolex watch remains waterproof!
- New crowns, should always have new crown gaskets.
- Case Post should have a new post gasket. Sometimes it is on the outside, sometimes on the inside, and in some cases, both.
- Make sure that the back cover has a new, and properly sided case back gaskets. I always tread these with a bit of waterproofing solution so that they don’t dry out.
- The very thing that almost everyone avoids, is the Crystal Gasket. This gasket is equally important. The older your watch is, the more this gasket will be affected by UV light as it is the only gasket that is exposed to light.
Depending you whether you’re comfortable to do this yourself, or if you take it to a watchmaker, the prices will vary tremendously. Always get a quote. Most of all, if you take it to a watchmaker, or ask me to help you, then tell me how you wear your watch, because that will help us to make the correct suggestions for you.
I sure hope that this helps, and if you have any questions, please let me know…