Jump to content

Omega with plastic case back

LiamB

By LiamB
in Watch Repairs Help & Advice

 Share

Recommended Posts

LiamB Member

LiamB

Posted
Posted

I have an omega with a plastic case back. I am fairly sure that it's not original and that ithe acrylic glass was added at some point and has cracked around the edges. Does anyone know how to remove this so the watch can be serviced? 

Thanks

IMG_1112.JPG

IMG_1113.JPG

Link to comment
Share on other sites
  • 6 months later...
philipk5 Member

philipk5

Posted
Posted
2 hours ago, marcoskaiser said:

Hello Liam! Please let us know how did it work. I have a venus 170 missing the case back, and started to consider this option.

On the basis that the cost being minimal, and you do no damage by using glue, why not give it a go? I have successfully used acrylic crystals as case backs on several watches that would otherwise have been scrapped. 

Phil

Link to comment
Share on other sites
marcoskaiser Watch Enthusiast

marcoskaiser

Posted
Posted
1 hour ago, philipk5 said:

On the basis that the cost being minimal, and you do no damage by using glue, why not give it a go? I have successfully used acrylic crystals as case backs on several watches that would otherwise have been scrapped. 

Phil

That’s encouraging. I will do so. Thanks for the push!

Link to comment
Share on other sites
marcoskaiser Watch Enthusiast

marcoskaiser

Posted
Posted (edited)

I could not resist and started to make a case back to eventually fit a sapphire glass. I took an old orient case as raw material.

On the lathe, I gave up mesuring and only listened to the cutting to get hairs off the internal diameter of the stainless ring. Got a fit, but also a question: those of you who made the thing for real, what quality/hardness stainless steel should be used? And is there an optimal angle for the fittings of these click-on backs? 

Thanks!

marcos

7D3016AC-6F56-4DC6-B85A-4082B27AEC14.jpeg

537CA103-5280-466C-867D-122929CB5EB7.jpeg

Edited by marcoskaiser
Accuracy
Link to comment
Share on other sites
nickelsilver Distinguished Member

nickelsilver

Posted
Posted

316L is the standard stainless for watch cases. Around 3-4 degrees for the angles, you don't want a sharp lip though, there will be a cylindrical land. Fitting is of course a bit of trial and error so a good fixture that allows removing and replacing on the lathe without introducing eccentricity is a must

  • Like 1
Link to comment
Share on other sites
marcoskaiser Watch Enthusiast

marcoskaiser

Posted
Posted
4 minutes ago, nickelsilver said:

316L is the standard stainless for watch cases. Around 3-4 degrees for the angles, you don't want a sharp lip though, there will be a cylindrical land. Fitting is of course a bit of trial and error so a good fixture that allows removing and replacing on the lathe without introducing eccentricity is a must

Thanks nickelsilver! I turned a brass holder and left it on the chuck until the end. Only trouble was securing the steel. I used cianoacrylate, and washed it with acetone to release the piece. But heat would melt the glue. Must research some glue for this purpose. Any thoughts?

Best,

 

Link to comment
Share on other sites
nickelsilver Distinguished Member

nickelsilver

Posted
Posted

I use cyanoacrylate very often, it's super handy. For something like this case I might use a friction chuck, usually plastic (pvc or delrin), that the case fits onto. Typically a short spigot that friction fits an inside diameter and a square shoulder to butt up against. Of course it only holds for light cuts with sharp tooling.

There are fairly sophisticated chucks that can be used but friction chucks are the traditional method, in the past they were generally wood.

Link to comment
Share on other sites
marcoskaiser Watch Enthusiast

marcoskaiser

Posted
Posted
4 hours ago, nickelsilver said:

I use cyanoacrylate very often, it's super handy. For something like this case I might use a friction chuck, usually plastic (pvc or delrin), that the case fits onto. Typically a short spigot that friction fits an inside diameter and a square shoulder to butt up against. Of course it only holds for light cuts with sharp tooling.

There are fairly sophisticated chucks that can be used but friction chucks are the traditional method, in the past they were generally wood.

Wood is surely more sustainable and cheap than brass...

I noticed that sometimes people like clickspring (makes videos on tooling and clockmaking) use some kind of superglue to hold metal together. 

At 6:54, if you get bored...

 

Link to comment
Share on other sites
 Share
Go to topic listing


  • Recently Browsing

    • No registered users viewing this page.

  • Topics

  • Posts

    • Jon
      Introducing myself

      By Jon · Posted

      Hi there  
    • Jon
      Movement inserted from crytal side

      By Jon · Posted

      Put the movement in a movement holder and it will be supported as you push down on the setting lever post to release the winding stem. Make sure the post is over the shoulder of the movement holder so what you are pressing down on is supported. As a general rule, hold the movement and not the movement holder. Replace the hands when the movement isn't in the case and support the centre jewel (if it has one) on a hard surface or staking block when replacing the hands to stop the jewel accidentally moving or even coming out. A dedicated movement holder with a central jewel support is even better, but pricey
    • JohnR725
      Main spring

      By JohnR725 · Posted

      It might help us if we knew which watch like model number.
    • Zedster
      Movement inserted from crytal side

      By Zedster · Posted

      Hi, guys I have a bit of a predicament and hopefully, somebody can advise. I'm working on a Roamer MST 521 where the movement is extracted from the crystal side. I'm now at the final hurdle where I need to replace the movement back into its case but I'm not sure of the correct procedure. I still need to fit the hands but that's where the problem lies. If I insert the winding stem to test the hands for correct alignment I will need to turn the movement over to release the stem again it's the spring-loaded type and needs a small bit of force to push down but with the hands fitted, I don't think I can do this on a cushion without causing some damage to the hands and that's the last thing I want to do, this watch has already been a love-hate relationship and I'm so close to boxing this one off which I'm counting as my first major project.  The other option is to case the movement then fit the hands and hope everything is okay. I've already broken the original winding stem but managed to find a replacement, the last one in stock, so I'm a bit reluctant to keep removing it. Any suggestions would be appreciated. 
    • Jon
      Main spring

      By Jon · Posted

      I would go for the dearer spring. You won't need to remove the spring from the carrier ring and then use a mainspring winder to get it into the barrel, for a start. Also that spring is closer to the needed dimensions, especially the length. The length plays a part in the mainsprings strength. If you double the length you will half the force (strength) of the spring and vice-versa. A spring with 20 mm less length would be about 7% shorter, so technically would be 7% more strength, but I find halving this number is closer to real-world findings, so the spring would be about 3 to 4% more strength/force. On a mainspring that ideally kicks out 300 degrees of amplitude, a 3% increase in amplitude would be 309 degrees. Increasing or decreasing the length of the mainspring will affect the power reserve to a greater or lesser degree. It depends how much shorter or longer it is. I've attached a lesson regarding mainsprings, focussing on the size and strength of the spring within the barrel, you might find helpful. Unfortunately it is a PDF converted from a PowerPoint presentation, but only a slide was lost that was originally a video of fitting a mainspring   Lesson 5 The mainspring.pdf
×
×
  • Create New...