Drawing-pin domed acrylic crystal

Its name describes its outline well: seen in profile, the drawing-pin crystal looks like the head of a drawing pin, with a domed central section rising above a flatter collar around the edge.

A profile typical of certain vintage watches

This type of acrylic crystal (Plexiglas, hesalite) is often found on older watches with a narrow bezel and a dial set off by a pronounced central relief. It is generally suitable for cases that already had a crystal of this shape; if in doubt, compare the profile of your old crystal with this one.

Acrylic: light and safe, but prone to scratches

Plexiglas is a lightweight material that does not shatter into sharp fragments. Its hardness is low: it scratches easily, especially on the domed section, which is the most exposed. These scratches can usually be polished out with a suitable paste. Find the technique in the guide to polishing an acrylic crystal.

Determining the diameter

Where to measure?

Use a calliper and measure the old crystal at its base, meaning the outer edge of the collar, not the central dome.

How much margin to allow?

An acrylic crystal is generally fitted slightly larger than its seat, as it is compressed when fitted and then expands to stay tight in the bezel. The margin depends on the case; the measuring guide helps you get it right.

Sizes of this crystal

See the table below to choose from the available drawing-pin diameters.

Available diameters