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Clock Crystals – Glass Variations
Let us explore the variety of clock crystals, because the glass does have many variations. The size options are vast, however the shape requirement may not be available in the size that you need.
The first step is to identify if the glass is square, round, oblong or some other odd shape. If the glass is round, need to determine if it is convex or flat. The following paragraphs will clarify each type.
Round Convex Clock Glass Variations
Clockworks offers a large number of sizes in round convex glass. Convex means that the glass has a slight bubble to it. The glass will not be perfectly flat.
Sometimes people may say it is concave as well. This type of glass that has a bubble is found on many mantle clocks as well as many other clocks. Clockworks stocks almost every size. In addition, most small sizes are available in 1/16 increments.
Please see the product page to see the sizes available and to order the glass. Ordering is simple once you know the size that you need. Just select the size from the order button menu. Measure the round convex clock glass from one side to the other.
It is the overall diameter of the glass. Do not try to measure the side that has the bubble. Trying to do so will result in the wrong size of glass. Turn it over and measure across the flat side.
When working with a clock bezel it is important to order the right size of clock glass. If the glass is too narrow, it will fall out the front.
When a clock glass is too wide, the tabs on the back of the bezel will not be able to fold over to hold it. It needs to be between the extremes. A good fit where the bezel tabs can hold it in place.
Round Flat Clock Glass Variations
Clockworks offers flat round clock glass in many sizes. If the glass needs to be any other size than what we offer, there is a solution. Because it is only flat glass, any local glass shop can cut a circle to whatever size you need.
It will not cost much, and as long as the measurement is correct it will be perfect every time. Sometimes just taking the bezel in is enough for a glass shop to cut it.
Square Clock Case Glass
Again, go to the glass shop for this one. Some glass shops will install the glass on the wooden clock case doors if it is left with them. This is the best way.
The glass will not be found by any clock part supplier. Bringing it to the glass shop will not cost much. Also there are more options available if changing the look or type of glass.
Clock crystal oddities
During the 1950’s through the 1970’s there were some unusual clocks made that had odd shapes for the glass. If the clock glass needs to be convex or any other shape besides round, there is not much hope.
Unfortunately no clock supplier will have this. Another solution is to find a similar clock and use the glass from it. Again, if flat glass can be made to work, a local glass shop is the way to go.
Can a clock dial/face determine the age of the clock? The design in the face of my grandfather clock follows through to the pendulum and also the weights. Any idea of the age?
Maybe, pics please
What are the numbers off of the back plate of the clock movement itself? If it is hard to get to, usually you can stick a cell phone up behind the movement and get a picture of the numbers. Or through the side access panel if there is one.
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
178368
Pictures are not a problem, James, it is how to attach to a message!!!
Do not have much to go on here, but that style weight cover was popular with German Gustav Becker late 1800s, usually chain driven / two weights / time – strike / with a round dial / 8 day run time
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
The clock and the chain tags are stamped with WH which should translate to Winterhalder & Hofmeier. This is a beautiful old German grandfather clock.
Very nice. Those are great quality units and a pleasure to work on.
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
What a great article thanks for this.