I have a 1918 Hampden with a loose crystal. I've not mounted a crystal before and don't want to mess it up. The crystal is glass and slightly loose in the bezel (not a press or snap fit).

What is the proper glue to use?

Tips on how to do a nice, neat job would be appreciated.

I might install a new crystal if I can find one that will fit. What's the proper way to measure the bezel so I know the correct size to look for?

Thanks in advance for any advice on this.

If you need a 42.4 mm let me know. I have a bunch.

Christopher this subject has been discussed many times and here is one link that may be of help....

Crystal Installation....there are other discussions regarding the subject also....just type the word "Crystal" or more specifically "Pocket Watch Crystals" in the search tab at the top of any page....

Good luck,

Jerry

I purchased a caliper from a local chain home supply company and measure my bezels as William suggests on his website and use the cross reference data and send my request to William and have been very satisfied. I don't have the fancy tools that the old watchmakers have that would heat up and hold the bezel while you popped the new crystal in but I found you can im most cases heat them up in the oven at low temps and that works ok also. It is hard to beat the price and quality and I usually look to see if William has any specials up so I can order more that one to make the shipping cost effective.

William's crystals are the greatest! He's replaced several crystals for me and they are all beautiful. I recommend him highly.

I plan to sell this particular watch. I took the bezel off to inspect the dial and hands and the glass popped out. It would be nice if I could just pop it back in.

The crystal is a little small (it's loose in the groove) and would need to be glued. It also has a couple of tiny edge chips so I'm considering installing a new crystal, as long as I am doing the work anyway.

I would like to learn how to do this work. I've not known if the glass is supposed to just snap into place or if it should be mounted with an adhesive.

Claude's post suggests that the glass should fit precisely, presumably without any glue, and that heating the bezel would enable the crystal to snap into place without damaging the edges.

I had never considered using heat, but it makes perfect sense (especially at a time when exotic adhesives weren't available). I would love to learn more about how this is done.

What I've done to get crystals to fit is this;

Measure the bezels inside lip and get a crystal the next size up, so if you got 42.9mm (19 0/16th) then get a 43.0mm (19 1/16th).

Then I use a coffee maker machines heating tray to warm up the bezel, while the crystal is in the freezer.

I then lift the warmed bezel off the plate, get the chilled crystal and place it on top of the bezel and gently apply pressure and the crystal will snap into place.

Done this way too many times, and it's crude compared to a master repairman, but it works and I've only had 2 crystals crack due to temp differences between the glass and the metal out of at least 100 jobs.

So when you know the size, order 2 just incase.

Roland

I bought 480 crystals off of ebay a few months ago and have had nothing but problems trying to heat them up to set them. So I turned to glue. I use crazyglue from the dollar store. My wife is a diabetic so I have access to fine needles to apply the glue in a bead that is hard to see. Any excess I wipe away with nail polish remover.

Hello Christopher and everyone,

If you have a crystal that is already a close fit then cement can be used to secure it, in fact, I would recommend cementing anything that is going to see use as a carry timepiece, no matter how snug the fit is, it can still pop out. For this job I use a clear 2 part epoxy. U.V. cured cement that is made for this purpose is also very strong but the advantage of using epoxy is that it can be softened and removed via boiling in water. Super glue should be avoided as it dries brittle and can leave a foggy mess on adjacent surfaces. The way I cement a crystal in place is to apply several drops around the bezel opening with a small dip oiler, put the crystal in place then turn it slowly (if it's not too tight) to spread the cement evenly. Heating the bezel is a great way to fit a glass tightly and although I don't use this method it has been used for many years and will eliminate the need for any cement...if done properly. The crystal can have no edge damage or rough areas as they will certainly develop into much larger damage once the bezel cools and contracts to its original dimension. Enormous pressure can occur here and transversely, the bezel must also be free of any dents, damage or debris where the crystal seats.

I hope this is helpful.

William

What do the numbers on crystal labels mean? I'm looking at a photo of a VTF crystal on E-bay. The label has the numbers 18 14/16, 17 6/8, and 7. I presume the 18 14/16 is the Ligne measurement. (How do you pronounce "Ligne"?) What does the 17 6/8 and the 7 refer to?

Christopher,

18 14/16 refers to the ligne (pronounced line) measurement. 17 6/8...I don't know. 7 refers to the height which means it's probably a hunting glass 1 is the highest and 8 is the lowest (nearly flat).

William

One interpretation is that the Ligne is the whole number and the fractional number is a portion of (I believe) a ligne. If you multiply the whole number ligne by 2.25583 you get a metric (mm) equivalent. Then, multiply the numerator (top number) of the /16 fraction by 0.141. Then add the two numbers to get a metric size crystal. Some crystals have the metric measurement listed under the Ligne number, ie 424 is 42.4 mm but as you can see the decimal is omitted.
William, check this for accuracy as you know more than I do about these things.

I have some of that U.V. cured cement also, it never sets up. I have left watches in the sun for hours.

Jim, I have had good luck with it in direct sun, not behind a window. I think it takes about 10-20 min.

Jim, I have a little u/v lamp. Works great.

Here's a crystal size chart found easily on the web showing the conversion between Ligne and metric.

I too have used the UV glue with great results even in winter with bezel placed on a window sill indoors.

I purchased two of Mike's 42.4 mm NOS crystals with labels attached. I measured their overall diameter, with my new digital caliper, at 42.25 mm, 0.15 mm smaller than the nominal size. This could be why Roland uses the next larger size.

In this case, the next larger size is 42.6 mm. If the actual size of the 42.6 mm crystal is also 0.15 mm smaller, it would be 42.45 mm. The heat would only have to expand the opening by 0.05 mm to fit the glass

Chris, PLease be careful with that Caliper, the (China Made) one I bought deviates by about +/- 0.7 mm all the time. Something to do with the slider fit allowing the jaws to spread making the read dimensions look smaller.

With a more accurate system I have check size accuracy of several dozen White Crystls and the deviation is well under 0.001" 0.025 mm

I have made a bezel warmer. Purchased a halogen light from Home Depot for $39.00 and turned a piece of aluminum to fit over the top. I measured the temp with a digital candy thermometer. The high range of the therm is 322 degrees. The temp of the aluminum went past the high range. Have only used it once and it was very easy. Need to be careful when removing the bezel. It's HOT.

Neat looking, Paul, You do good work for an old guy.

Here is a printable chart on site...

CLICK: Ligne Conversion Chart for Glass Crystals