Station: [19] A Closer Look at Enamel.


Bathtubs, milk pots, camping plates, historical road signs: we’re all familiar with enamel. But ... what exactly is enamel?

A professional would say: enamel is glass on iron: Treat it like glass, and it’ll last like iron.

That’s actually true: enamel vessels are highly resistant to acids and alkalis and extremely durable. The main ingredients of enamel are quartz sand, feldspar, sodium carbonate and alumina (or aluminium oxide), to which various other oxides and appropriate pigments are added.

But durable and hygienic as enamel may be, if you don't treat it like glass, you’ll soon ruin it. A hard impact can cause chipping of the enamel coating and rusting of the metal underneath. The advantages of enamel are quickly lost.

The Metal-Punching and Enamelling plant first started producing enamelled household items here in 1835. Let’s take a milk pot as an example. Before it could be enamelled, you needed to produce the blank. Take a look at the model of the "Erfurt" multi-stage press, which was crank-operated. It shows the seven operations carried out by this single machine.

First, a disc is punched out of the raw material, the steel strip. It’s called a round blank. Then the blank is drawn into a pot in six further steps.

If you look at the intermediate stages from the round blank to the finished pot blank, you can see how the different punches gradually shape the vessel. You can even see the crank-operated multi-stage press in action – simply press the button on the right of the display case. You know you want to!

All depictions: © Hüttenmuseum Thale