Production

Restoration Glasses are produced by means of the traditional mouthblown method. The large red-hot balloon of glass must be kept smoothly rotating at a steady pace. This requires a good deal of experience, physical strength and craftsmanship on the part of the glassblower. The result is a well-proportioned glass-cylinder which will be scored lengthwise, heated again, opened and ironed out into a flattened sheet of glass.

The Transparent Sand.

Weighing the raw materials is the first step. Each type of glass is mixed individually. The daily output amounts to 26 different mixtures. [1 + 2]

Melted at high temperatures, quartz sand, sodium carbonate and limestone become completely clear after cooling. A batch having been entirely opaque before, changes into one of the most fascinating materials: glass.

After the mixing process the batch is loaded into ceramic pots to be melted in special ovens. The deciding factors of the mix are the structure desired, the colour and the style. [3]

: 01 - Quarts sand, sodium carbonate and limestone

: 02 - The batch

: 03 - Loading the melting pot

From Starter to Cutter.

The glass undergoes a refining process overnight and is prepared for the most important and most difficult stage of processing: the blowing of glass. [04]

Each of the ovens is operated by four teams. A team is comprised of the starter, the assistant and the master. The blowpipe is dipped into the pot by the starter and kept constantly rotating thus gathering the molten glass onto the end of the pipe. He repeats this procedure several times until the quantity required has been reached. By means of spinning and simultaneous blowing the starter works the "gather" through the different wooden molds to give it the appropriate shape. [05 + 06]

: 04 - Blowpipe

: 05 - The starter

: 06 - Starter

The gather of molten glass spinning in the mold is slightly inflated by the starter who finally passes the blowpipe on to the master [07]. While rotating the balloon in the steel trough the master continues to blow it to full size thus giving it the desired shape and structure [08].

: 07 - The gather of molten glass

: 08 - The master

This requires excellent craftsmanship, physical strength and, above all, a well-developed sensitivity. It is the only way to achieve the unmistakeable individuality of mouth-blown sheet glass.

The red-hot balloon is cut open at the front end [09] and dilated by means of the scissors and "fork" [10].

: 09 - Opening the balloon

: 10 - Widen the cylinder

The same procedure takes place at the other end after heating up the balloon again [11]. In this way a well-proportioned glass-cylinder comes into existence. The cylinder is placed in an annealing oven to remove any inherent tensions. At the end of this most important part of the production process, the finished cylinder must undergo quality control. Only then does the cutter score the cylinder lengthwise [12].

: 11 - Finished cylinder

: 12 - Cutting the cylinder

From Cylinder to Sheet.

Now the scored glass cylinder is heated again, layed open and flattened. [13]. The wave-like sheet is ironed out by means
of a special wooden tool [14].

: 13 - Opening the cylinder

: 14 - Flatten the sheet (Photo: COM PR + Marketing Fürstenzell / Scholz)

The flattened glass sheet travels on a continuous belt through a second long annealing oven thus losing any remaining inherent tension. The result is a beautiful cutting glass. After this annealing procedure each and every sheet must pass another quality inspection. Now the sheet is finished. [15].

: 15 - Restorationglass