Basic PW Crystal Installation Tool?

[John Hinkey]

I need to install crystals into at least two pocket watch bezels, what's the most basic tool that I need to use - I see many crystal installation tools on ebay, etc. but I'm not sure they will do what I need. Any recommendations for an economical PW crystal install tool would be great.

Also, is there another way to install the crystals into the bezel? Heat the bezel and freeze the crystal to take advantage of the dimensional change and then let them warm up? Buy the dies that I need and use a machinist's vise (which I have) to precisely apply the force? etc.

Really hard to spend hundreds of $$ on a crystal installation tool to use it 2 or 3 times . . .

Thanks -

John

 

[richiec]

Most old pocket watch crystal installations only require hand pressure or crystal cement to install, you just need to carefully measure the diameter of the bezel and go 1-2 mm larger or smaller to match. Most of the crystal assortments being sold these days are missing the most common crystals. I have hundreds of crystals that will never be used as most major case manufacturers used most of the same size. Ones about 1 mm smaller can usually be glued into place to clean up an old scratched crystal. You might need a tool for a wrist watch but usually not for a vintage pocket watch.

 

[Dave Coatsworth]

A slight correction to Richie's excellent reply... You measure the opening of the bezel and then add 0.1 - 0.2mm to get the correct size crystal to snap in without glue.

 

[John Hinkey]

A slight correction to Richie's excellent reply... You measure the opening of the bezel and then add 0.1 - 0.2mm to get the correct size crystal to snap in without glue.

Hah! I'll keep it oversized by the fraction of a mm . . .
Can you recommend a place to purchase a replacement crystal?

Thanks!

 

[Skutt50]

It is my experience that either the crystals or the bezel are not perfectly round. Rotating the crystal in the bezel to find the best position where the crystal and bezel match, makes the fitting easier. Sometimes when a crystal snapps in place the crystal is a bit loose. Again, rotating the crystal may yield a position in which the crystal stays in place.

 

[gmorse]

Hi John,

I need to install crystals into at least two pocket watch bezels, what's the most basic tool that I need to use - I see many crystal installation tools on ebay, etc. but I'm not sure they will do what I need. Any recommendations for an economical PW crystal install tool would be great.

You need to differentiate between glass and plastic crystals. The acrylic crystals are installed with a tool of some sort, either one which compresses the diameter of the crystal slightly before inserting it, or with the tension ring types, a straight pressure. Glass crystals clearly won't distort like plastic, so your suggestion of heating the bezel and cooling the crystal is a long-established technique. The old NOS glass crystals still available aren't necessarily completely circular, (and for that matter, neither are some bezels), so some manipulation and trying in various positions is often necessary. Buying a size each side of the measured size is usually a good idea. Sometimes it's necessary to use a crystal adhesive if the crystal is a little loose. A problem sometimes encountered with old stock crystals is that the label adhesive has etched the glass over the years and this shadow needs to be polished out with cerium oxide.

One supplier who makes and sells high quality new crystals is Whites, his prices are very reasonable, he's often referenced on the forum and he has a good reputation.

Regards,

Graham

 

[John Hinkey]

Hi John,


You need to differentiate between glass and plastic crystals. The acrylic crystals are installed with a tool of some sort, either one which compresses the diameter of the crystal slightly before inserting it, or with the tension ring types, a straight pressure. Glass crystals clearly won't distort like plastic, so your suggestion of heating the bezel and cooling the crystal is a long-established technique. The old NOS glass crystals still available aren't necessarily completely circular, (and for that matter, neither are some bezels), so some manipulation and trying in various positions is often necessary. Buying a size each side of the measured size is usually a good idea. Sometimes it's necessary to use a crystal adhesive if the crystal is a little loose. A problem sometimes encountered with old stock crystals is that the label adhesive has etched the glass over the years and this shadow needs to be polished out with cerium oxide.

One supplier who makes and sells high quality new crystals is Whites, his prices are very reasonable, he's often referenced on the forum and he has a good reputation.

Regards,

Graham

As usual - thanks!
Since I have a hunter case I need to find one low enough to not crash into the case when closed, but high enough to miss the hands.

 

[Skutt50]

Since I have a hunter case I need to find one low enough to not crash into the case when closed, but high enough to miss the hands.

In my experience the hunter case crystals are a bit tricky (not to crash or hit the hands as you desribed but also) because of their thin glas. They break very easily. Personally I don't search for a tight fit with these. I rather leave them "a tiny bit loose" than breaking them.

 

[John Hinkey]

In my experience the hunter case crystals are a bit tricky (not to crash or hit the hands as you desribed but also) because of their thin glas. They break very easily. Personally I don't search for a tight fit with these. I rather leave them "a tiny bit loose" than breaking them.

And then would you glue them in with some UV-set clear glue? Or just leave them on the loose side with the possibility that they might come out?

 

[Skutt50]

And then would you glue them in with some UV-set clear glue? Or just leave them on the loose side with the possibility that they might come out?

I usually leave them without any glue however they are not that loose that they come out on their own...... There must be a fit that keeps them in place of course but when i fit a normal crystal I want it to be a bit tighter.

In the beginning I was a bit puzzeled when i found hunter watches with crystals that could be moved around easily and I tried to change them for tighter fit. After breaking some crystals I gave up and started accepting a looser fit.

 

[John Hinkey]

Here are my measurements:

Mr. White will not recommend anything based on my measurements, so I'm going to re-measure (measure three times order once I say) and get something 0.1mm larger in diameter than my smallest measurement.

Height:

H-8 = 0.8mm
H-7 = 1.2mm
H-6 = 1.6mm
H-5 = 2.0mm
H-4 = 2.4mm

I will likely go with an H-6 if my measurements hold up. I suspect this will be an iterative process.

- J

 

[John Hinkey]

Ah, some new measurements to determine the glass I need:
H-7: 1.2mm height
39.10mm diameter


Looks like some UV glue is in my future as well.

- John

 

[gmorse]

Hi John,

Is your range of diameter values to allow for the undercut of the crystal seat in the bezel?

Regards,

Graham

 

[John Hinkey]

Hi John,

Is your range of diameter values to allow for the undercut of the crystal seat in the bezel?

Regards,

Graham

My diameter range is the spread of my bezel opening measurements at 4 locations around the ring, which are:
39.12mm
39.09mm
39.06mm
39.07 mm
So it's not quite round.

Thus the 39.1mm diameter might drop/snap in or it might need the ring heated just a tad to drop in.
Mr. White does not like heating the ring as he fears that it will compress the crystal after cooling, but I think if one does not go overboard on the diameter mis-match it will be OK. It's difficult to know the bezel diameter underneath the entrance.
I'm contemplating doing a 39.2mm in addition to the 39.1mm if the 39.1mm is too loose after getting it in.
He can also do a 39.05mm which seems guaranteed to drop in, but certainly will require UV glue to have it stay put.

Any suggestions on two sizes to have him make based on my measurements?

- John

 

[Skutt50]

I would get 39.1 and 39.2.

39.1 might be too small so a backup at 39.2 should do the trick.

 

[John Hinkey]

I have a 39.10 and a 39.05mm on the way (both H-7 thick) + UV crystal glue from Esslinger.
Mr. White manufactured and put these in the mail before I even wrote him a check for payment.
A very nice guy!

 

[John Hinkey]

Well, Mr. White got me my crystals today.
I quickly tried the 39.05 and it would just gently snap in and not directly fall out, but would likely require some UV glue (which also arrived today from Esslinger). The 39.1 would not go in with my initial gentle effort, so I think I will heat up the bezel ring and drop in the 39.1mm and see how it goes - this might need to be glued is as well.

I will also need to check that the crystal has sufficient clearance from the hands and the case.

Pictures tomorrow.

 

[Skutt50]

Did you try rotating the crystal?

 

[John Hinkey]

Did you try rotating the crystal?

No, I forgot to do that. I will try again. It was definitely not loose though.

Mr. White is a first class guy. Made and shipped me my crystals before I even had a check in the mail to him and they arrived exquisitely packed. They look fantastic!

 

[gmorse]

Hi John,

I suspect that Mr. White's newly-made crystals will be much more accurately circular than many of the NOS crystals you may come across.

Regards,

Graham

 

[darrahg]

Did you know that crystals can be downsized? I use fine and extra fine diamond files when a crystal is slightly larger than needed. It has to be done carefully with a little patience and around the entire circumference of the glass. I try and keep the edge in the same original shape if possible.
I have an vintage machine that is used for this purpose. It uses the flat surface of a fine grinding wheel with water. I don't use it now because the water reservoir needs to be replaced.

 

[John Hinkey]

Did you know that crystals can be downsized? I use fine and extra fine diamond files when a crystal is slightly larger than needed. It has to be done carefully with a little patience and around the entire circumference of the glass. I try and keep the edge in the same original shape if possible.
I have an vintage machine that is used for this purpose. It uses the flat surface of a fine grinding wheel with water. I don't use it now because the water reservoir needs to be replaced.

For $20+ shipping per crystal I'll just order a different size if the one's he has supplied don't work.

I will install the 39.05mm temporarily in the bezel and install it on the case with the movement installed and make sure the height is good for both clearing the minute/hour hands and closing the case. Then we'll see which of the crystals I will actually install. Really don't want to use UV glue unless I have to, though it would make sure that whatever crystal I install won't fall out.
- J

 

[darrahg]

Best wishes on your repair

Oh, I did want to mention that I use a minor amount (only in the recess) of epoxy on most of my crystal replacements mainly because I was taught that way but also to create a reasonable air tight seal for the dial/movement area.

 

[Dave Coatsworth]

I suspect that Mr. White's newly-made crystals will be much more accurately circular than many of the NOS crystals you may come across.

White's crystals are indeed perfectly round (at least to the tolerances we are interested in).

 

[John Hinkey]

Good news. The 39.05mm easily snapped into the Bezel and I installed it over the dial with the hands installed. The height was sufficient and it was low enough to not touch the case when closed.
Bad news is that when I popped out the Bezel the 39.05mm crystal also popped out.

So I tried the 39.10mm crystal and was able to satisfyingly snap it into the Bezel and it survived being installed and un-installed from the case.
Therefor I'm just going to let it be and not glue it in place since it seems to be just fine w/o glue.

Here it is with the new crystal installed and some hand polishing of the double hunter case:


I think I'm done . . . for now.

Thanks for the help!

- John

 

[gmorse]

Hi John,

Congratulations! On to the next project now.

Regards,

Graham

 

[John Hinkey]

Hi John,

Congratulations! On to the next project now.

Regards,

Graham

Yes, I have a Tavannes open face 1920's PW that needs some serious TLC and a 1890's private label ladies sized Agassiz that hopefully won't need any parts other than a bezel/crystal. Also figuring out a 1920s Hamilton 912 reconstruction too.

 

[Dave Haynes]

Whites? If I recall it is Bill White. He's been doing this stuff since I started working on watches with Dean Judy. Bill and Dean for that matter are the real deal. Honest and fair.

 

[John Hinkey]

Whites? If I recall it is Bill White. He's been doing this stuff since I started working on watches with Dean Judy. Bill and Dean for that matter are the real deal. Honest and fair.

Yes, William White. Been great to work with.