Replacing or Enhancing the Crown post?

[SQ19HRLGY]

Hello,

I have a watch with a very basic waterproof crown with a flush post/hidden gasket. 

I've read elsewhere that the best thing to do is to simply replace these types of crowns.

However, I'd like to somehow waterproof my watch without replacing this crown.

I'm (likely naively) wondering if i can replace the post to a japanese-style post to waterproof, or if I can use extenders and somehow sandwich a gasket between the thicker parts.

So in brief:

1. Is there a way to remove/replace the existing crown post? (I've seen crown posts being sold but am not sure how that works)

2. Are there any other options for waterproofing this type of crown?

Thank you!

[StuartBaker104]

It would help if you could tell us what the watch is and post some pictures, then tell us a little about your knowledge / ability. Some watch manufacturers have unique crown types which are difficult to replace. Some use very standardised parts. For some it is possible to get new replacements, for others it’s almost impossible. 

[SQ19HRLGY]

Here are some photos! I attempted to take photos of the inside of the crown but its proving to be rather difficult.

I'm a complete novice, but I am willing to take this to a skilled watchmaker or slowly take the time to learn/practice to get this to work.

This is a very cheap but personal quartz Wenger Swiss Army (70181) that I'd like to try and keep original externally.

I'd like to be able to waterproof this crown without needing to get a new crown altogether.

Is there a way (I'm open unorthodox approaches) to add gaskets on this to restore the 100M water resistance?

[jdm]

With some bent pick, clean out what remains of the gasket inside the crown, try to measure it the best you can and order a replacement from Cousins UK. Or replace the entire crown. There isn't anything else that you can practically do.

[oldhippy]

Why would you want to keep a dirty old button? Fit a new one.

[clockboy]

Agree with Oldhippy just replace the crown. If you want to truly waterproof the watch you would have to change the pipe to a screw down pipe & screw down crown. 

[jdm]

1 minute ago, clockboy said:

If you want to truly waterproof the watch you would have to change the pipe to a screw down pipe & screw down crown. 

That is for a diver's watch really. Screw down doesn't do waterproofing, it's just a safety device to prevent accidental pulling of the crown. Good waterproofing can be had with o-rings in the crown, as in this case, or on the stem.

[clockboy]

Depends on how many atmospheres the watch is going to be subjected too. All truly waterproof watches must have a screw down crown. The weakest part with regards to water ingress is the crown & pipe. 

[jdm]

31 minutes ago, clockboy said:

Depends on how many atmospheres the watch is going to be subjected too. All truly waterproof watches must have a screw down crown. The weakest part with regards to water ingress is the crown & pipe. 

Yes, screw down crown is a requirement for a diver's watch, for which there is an international certification, ISO 6425

https://en.wikipedia.org/wiki/Diving_watch

However, as mentioned above, a screwed crown in itself does not have any waterproofing capability. You can try that yourself, remove gaskets on a screw down watch and do a pressure testing.

 

 

[clockboy]

The screw down crown adds pressure to the seals thats how they work better than just a seal.

[jdm]

1 hour ago, clockboy said:

The screw down crown adds pressure to the seals thats how they work better than just a seal.

Not really. If you think about it, the screw down crown threading is just a retention mechanism. Seals are in between stem and inside pendant tube, and/or crown and and the outside of the pendant tube. They are not influenced by the screw down as it's "force vector" does not change their position. 

[Marc]

16 minutes ago, jdm said:

Not really. If you think about it, the screw down crown threading is just a retention mechanism. Seals are in between stem and inside pendant tube, and/or crown and and the outside of the pendant tube. They are not influenced by the screw down as it's "force vector" does not change their position. 

If the design of the crown incorporates a gasket that locates between the end of the case tube and the underside of the crown (Rolex Twinlock & Triplock, Vostok Amphibia) then screwing down the crown most definitely improves the seal as it increases the compression on the gasket.

http://blog.watchdoctor.biz/2016/10/09/rolex-screw-crown-works/

[StuartBaker104]

Meanwhile, back at the original question, I think it’s important to establish the objective, and then clarify the options and outcomes. The OP describes an ambition to get back to the original 100m waterproofness, so let’s look at that.

JDM’s answer above is about the extent of it.

If you can find an accrediter repairer who has a Wenger parts account, they may be able to obtain a new crown with the Wenger logo on it.  They will fit the crown using the correct grade of loctite to attach it to the stem, if necessary, they can replace the case tube, they will lubricate the stem and seal with the correct lubricants (both different), refit the stem and a new caseback seal (also lubricated), and then pressure test to confirm all is good.  My guess is that this would cost £70 to £100.  If the correct crown is not available then a similar style generic one could be fitted and the cost could be a little less.

A quick google search suggests that someone like InTime might be able to do this.

It is unlikely you will find a repairer who is willing to fiddle around with trying to replace the crown seal.

If you want to tackle this yourself then you have the choice of trying to find a replacement o-ring as JDM describes, or a generic crown. Loctite is optional, but adds security against the crown coming off, so I would reccomend. A pin vice is preferable to hold the stem, but smooth jawed pliers would do for a one-off. Silicone grease for the seal is recommended, but you could get away with not greasing the stem. So you should be able to do all this for around £20. You may need to shorten the stem or pack the hole in the crown if it’s a little short... read the sticky thread on fitting a new stem. Let’s assume you don’t want to spend hundreds or more on a pressure tester, so you will be guessing that all is good when you've finished.

You pays your money and takes your choice.

 

 

 

 

[jdm]

12 minutes ago, Marc said:

If the design of the crown incorporates a gasket that locates between the end of the case tube and the underside of the crown (Rolex Twinlock & Triplock, Vostok Amphibia) then screwing down the crown most definitely improves the seal as it increases the compression on the gasket.

Correct. But Twinlock and Triplelock are the (patented) very best of crown lock mechanisms, with features not found on the large majority of other watches, for example the extremely popular Seiko divers (O-ring on the stem), or IWC and other Swiss watches (O-ring inside the the crown). These others make about 99% of screw down crown watches ever made, from that my point above explained.

Edited December 4, 2017 by jdm