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Pressure testing a "Watchco" SM300

O
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My first post!
Interesting topic, love stuff like this. Especially as I have just bought a gorgeous new 300M!
So at the equivalent of 300m depth the pressure on the case would be 438 psi, so assuming the crystal has an area of approximately 1 sq inch, that's the sort of force it would see.
Supported only around its perimeter some deflection is to be expected.
Couple of questions if I dare!
How thick is the crystal? and what is it set in?

Alan
 
Archer
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O Omega alan
My first post!
Interesting topic, love stuff like this. Especially as I have just bought a gorgeous new 300M!
So at the equivalent of 300m depth the pressure on the case would be 438 psi, so assuming the crystal has an area of approximately 1 sq inch, that's the sort of force it would see.
Supported only around its perimeter some deflection is to be expected.
Couple of questions if I dare!
How thick is the crystal? and what is it set in?

Alan

Area of the crystal is about 1.16 square inches...

Crystal is about 3.3 mm thick, and it is set in the case - not really sure what you mean by that question to be honest...
 
O
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Wow, that's quite a chunky piece of crystal!
Sorry that is a bit vague.
I wondered what it was actually sealed into the case with - epoxy, silicone product or similar.

Alan
 
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O Omega alan
Wow, that's quite a chunky piece of crystal!
Sorry that is a bit vague.
I wondered what it was actually sealed into the case with - epoxy, silicone product or similar.

Alan

Friction. This is a crystal that uses a tension ring inside it, which is a metal ring that helps keep the crystal from compressing too much as it is pressed into the case.

Cheers, Al
 
O
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That's amazing, I guess the machining tolerances must very controlled to avoid breakage, and to make it more difficult the front of the crystal is convex!
Must say that having the anti reflective coating in and out makes it look like it doesn't have one fitted!

Alan
 
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O Omega alan
That's amazing, I guess the machining tolerances must very controlled to avoid breakage, and to make it more difficult the front of the crystal is convex!
Must say that having the anti reflective coating in and out makes it look like it doesn't have one fitted!

Alan

I am referring to the watch this thread is about, which uses an acrylic crystal.

You appear to be referring to a modern watch, which would use a sapphire crystal. It is also held in with friction but via a plastic seal. This seal fits into the case and provides a slight interference fit with the OD of the crystal.

The plastic seal is a hard plastic that deforms on installation and can't be used again as it would not provide the same amount of holding power.

Cheers, Al
 
O
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Thanks for all this information, I love to learn.
Yes, I was basically referring to my new 300M.

Alan
 
jayhawks
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Al, greetings! This post and a number of others inspired me to buy a brand new Watchco 300. It just arrived yesterday from NZ. I opened it after work, placed a strap on, and set it in my winder overnight. Went to wear this morning and it’s not running? Any tricks to get the Cal 565 kickstarted if it’s been sitting awhile? Thanks! Chris
 
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jayhawks jayhawks
Al, greetings! This post and a number of others inspired me to buy a brand new Watchco 300. It just arrived yesterday from NZ. I opened it after work, placed a strap on, and set it in my winder overnight. Went to wear this morning and it’s not running? Any tricks to get the Cal 565 kickstarted if it’s been sitting awhile? Thanks! Chris

Hi Chris,

You can manually wind the watch using the crown, but if it hasn't built up enough of a charge being on a winder overnight, then the watch may be faulty. I would start by unscrewing the crown and turning it clockwise for 30 full turns to wind the watch - if that doesn't get it running, then you need to talk to the seller (I assume Watcho/abouttime) about sending it back as defective.

Cheers, Al
 
jayhawks
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Thanks, Al! I’ll give her a try and report back, sir.

Archer Archer
Hi Chris,

You can manually wind the watch using the crown, but if it hasn't built up enough of a charge being on a winder overnight, then the watch may be faulty. I would start by unscrewing the crown and turning it clockwise for 30 full turns to wind the watch - if that doesn't get it running, then you need to talk to the seller (I assume Watcho/abouttime) about sending it back as defective.

Cheers, Al
 
jayhawks
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Al, here is my follow up (and also what I sent to the seller, (abouttime):

Follow up: I unscrewed the crown and wound it clockwise 20-30 turns and it ran for a minute or two. It then got hung up shy of :45 and then released for one more minute or so. Came up shy of :45 and then stopped again.

 
efauser
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jayhawks jayhawks
Al, here is my follow up (and also what I sent to the seller, (abouttime):

Follow up: I unscrewed the crown and wound it clockwise 20-30 turns and it ran for a minute or two. It then got hung up shy of :45 and then released for one more minute or so. Came up shy of :45 and then stopped again.
Are any of the hands touching?
 
efauser
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jayhawks jayhawks
IMG_3831.jpg
I'm going to take that as a "no". That seemed the most logical reason for it to be stopping at the same spot.
 
jayhawks
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=)

Sorry, my text was cut off when uploading. I'm at a loss to what it's doing, but I've also never opened up a case back, inspected a movement. I appreciate the troubleshooting, as I'd prefer to keep it and get it running as opposed to sending it back.
 
Archer
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Well, you should at least get them to cover the cost of getting it serviced...
 
jayhawks
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So, I unscrewed the crown (from the screw-down setting) and the seconds hand took off again making a single pass around the dial before locking up again at the :40 mark.
 
jayhawks
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True, Al. That's what I have proposed in my note to them. Return or they cover Omega servicing the movement.
 
ChrisN
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The second hand is probably touching the crystal if it always stops at one point and it doesn't seem to be hand interference.

Unfortunately you need a Watchmaker who can re-align the hand(s).

Cheers, Chris
 
jayhawks
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Fellas, after a holiday spent pondering I have decided to return the watch. I do appreciate all of the advice. I think this one has a place in my collection someday, but I'm a bit thrown off by the whole thing.
 
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