I know many people will advise that I take this job to a watchmaker, but hey we all have to start somewhere...

I would like to remove the movement of my Uni-compax cal. 285 to measure the dial on my watch. I understand the basics of this job, but I have just a few questions, I was hoping maybe some forum members may have the answer to.

First, how do I remove the stem? Is there a screw that has to be loosened or removed? Or do I have to press a push button? Do I have to do anything special with the stem? Or do I just pull it out?

Second, aside from the stem, is there anything else holding the movement in?

Lastly, is there any sort of movement ring?

Thanks in advance

 

what dial measurements do you need? If you just need diameter than you might be be able to pop the bezel/crystal off the front and take direct measurements without messing with the movement. If you need the dial feet, that is WAYYYYYYYYYYY more involved. In order to pull the movement there are a few screws minimum holding it in place. Sometimes there is a ring. It really depends on the particular watch. I don't mess with my chronos, but I know with time only there both button release and screw release for the stem/crown. Sometimes even the same caliber will have both types depending on what generation it is. Push buttons will have a little dimple in the middle, screws will be obvious, so should be easy to tell which type. Once released it should just pull straight out.
At that point the entire movement/dial package should come out in one piece. Then you would have to pull all the hands, using the proper tools and a dial matt, then you would need to release the screws clamping down the dial feet, and THEN you could remove the dial to check the dial feet measurements. You would then have to do the opposite to re-assemble. Use finger cots and don't touch anything with your bare fingers.
Again, I have NEVER worked on any of my chronos and would not recommend you try this!!
It takes special tools, it's very easy to strip the screw heads, damage the dial and hands, etc.
If you really want to mess around with something, try a throw away time only that doesn't matter if you screw it up.
anyhow, my 2 cents...

 

Thanks for the response! I will definitely adhere to your advice. I just need the dial diameter. When you say pop off the bezel/crystal, would I do this the same way I would take the case back off?

 

Is it possible to grab the reference number of your watch and google it in order to find the diameter?

Doubtful you’re the first to gather this info.

 

Not possible as reference number has been completely polished off.

 

yes, using a case knife or razor blade, there is often a spot in the bezel where there is a slight gap. If it has been fitted correctly it should be opposite the crown. But sometimes it could be anywhere, including right over the crown. Or sometimes there is no discernible gap. But anyhow you want to VERY CAREFULLY work a tool between the mid case and bezel, until it comes off. Sometimes if you do this too vigorously the crystal can pop out of the bezel, but this is not likely, and if it did, you would need to correct tool to get the crystal back in. Anyhow the main thing you want to make sure is that you do not scratch the mid case or the bezel !! And even more importantly that you do not damage the dial and/or hands in any way when you remove the bezel !! Once it's off, you should be able to get precise diameter with calipers.
This is way more routine than removing the dial from the movement, but there is still possibility to cause major damage if you don't know what you are doing. That being said, I think a lot of people are comfortable enough removing a bezel.

 

Alright, I shall give it a try soon. Thank you as always.

 

that is just my opinion of course but i strongly advice you not to even start doing anything on the watch. without proper tools and knowledge you will just damage it one way or the other...

 

If i needed this done ... my watchmaker would happily do this at no to minimum charge. Please do your experimentation on worthless beaters not this. Just sayin.

 

Yeah, I almost started it and then decided not to. I think my problem is, I don’t really have a watchmaker in NYC yet.