Tool 107 , Omega Cosmics, Seamasters & De Villes

Jack Gertson asked, on the Chronocentric Omega forum,    "How do I remove the stem/crown from an Omega Dynamic". I Posted a quick 1 line answer & promised more details/pics......

Some of the pictures in this webpage expand, click on them & try your luck !

Jack asked about a Dynamic, but basically what I describe here, will apply to a number of Omega watches from the 60's thru to 80's. It DOES NOT apply to dive watches or watches with saphire/mineral crystals.

I used an Omega Cosmic to show the method. Here is my watch.
No blow up here, SorryNo blow up here, Sorry

Here are the tools that I will use.
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I'll explain a bit about each as we go, but to start with we want to concentrate on the Grey pastic tool on the right. This is the (in)famous Tool 107. Somewatches ( like my Cosmic ) have an inscription on the back about the tool.

Tool 107 is used to remove the crystal. Why is it called Tool 107 ? What are the others ?
Here they are
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Amazingly they are called Tool 101 thru Tool 107. I have 2 sets of these. I have never seen a Tool 100 ( or less ) or a Tool 108 ( or more ) Tool 105 & Tool 106 are red. They are each marked like this.

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The basic difference in the different tools is the diameter of the bottom.

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As you can see Tool 107 is a series of metal segments inside a a plastic cone, with a screw top.

Before you use Tool 107 on the watch, screw the black top anticlockwise, until the metal slightly protrudes below the plastic cone. Then you simply sit it on the crystal & turn the black top. This pulls the metal segments up inside the plastic cone, thus, closing them together & gripping the crystal. Eventually the crystal will be "gripped" so tightly that it will release itself from the case.

It's a good idea to line up the "notch" in the plastic cone with the crown.

click here for a blow up
& this is what it looks like with the crystal removed.
No blow up here, Sorry No blow up here, Sorry

Before we carry on, a slight aside.
How does Tool 107 grip the Crystal ?

This is a blow up of the crystal
No blow up here, Sorry
click here for a blow up

See the edge on the crystal ? I should point out that this crystal is not a genuine Omega crystal.

You can also use a Bergeon tool to achieve the same result. The Bergeon tool is shown , on the left, in the first picture on this page

Here's the Bergeon tool on a crystal.
click here for a blow up

The Bergeon tool works in a similar way to the Omega Tools.

Now obviously to remove the movement we have to remove the crown. It simply "pops" off. I used the tool shown in the 1st picture on this webpage. This levers the crown off ( only a gentle pressure is required ). As you can see the crown end of the stem is simply screwed into the crown.

click here for a blow up click here for a blow up

To remove the movement in this watch, you have to rotate the dial & movement ( as a single item ) about 5 minutes counter clockwise. Then you simply turn the watch upside down & the dial/movement will drop out ( Catch it ! )

Here's the movement end of the stem.
click here for a blow up click here for a blow up

The coloured rings on the previous pictures match the coloured rings in the next pictures.
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There are 2 "movement clamps" ( red rings ) opposite each other on the movement. When replacing the movement, drop it in so that "clamps" drop into the cutouts in the case. Then rotate the movement/dial 5 minutes to lock it into place. The next picture shows you where the stem/clamp drop into & rotate to.

click here for a blow up

There are different methods of holding a movement in the case. For some watches there is a sort of "locking ring" which you can see around the edge of the dial ( after removing the crystal ). To remove the movement, you rotate the locking ring. I will try to get some pictures of this system.

BEFORE you replace the crystal, line the movement half of the stem up with the crown tube, then push the crown part of the stem into the tube. It should "snap" into place. You may take a few tries to achive this.
Replacing the crystal is exatly the reversal of the above procedure. ( line the notch on the plastic cone up with the crown in order to get the magnifying window in the correct position )
Here's the "rebuilt" watch.
click here for a blow up

As you can see 20 minutes ( including taking pictures ) from start to finish.

I guess the only open question now is why do you want to do this ? You have to answer this for yourself !

This page was written by Steve Waddington & last updated on 1 November 2007

I have written this page to share the limited knowledge & information I have. Please don't abuse me, my work or other peoples pictures. It's not a nice thing to do !

Finally, It pisses me off that I have to write a disclaimer like this !

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