Posted 8 years ago
kralik1928
(202 items)
These glass boxes were produced by Franz Welz in Czechoslovakia circa 1925 to 1935. They have a distinctive line decor, also called line and confetti decor.
In the making: The base glass is "punched"by a vice tool or mold to create vertical indentations. The glass is rolled over ground glass (fine) then lager (coarse) chips of glass for contrast. When the piece is blown fuller, the indentations spread-out to show the base color and expose lines. The piece is then coated with a clear coat of glass (either molten or glass chips) then put into a mold to shape. Welz had amazing glass workers and supplies, they created glass with lots of depth and saturation of color for how thin these pieces are- 5 layers of glass in 2-3 millimeters of thickness.
BEAUTIFUL WELZ!!
scott
Thank you for the information, it's appreciated. Images too!
Fantastic pieces the colours are just gorgeous !!!!!!!!
I really enjoyed reading/learning from this post. Thank you.
Gorgeous
Good question, I'll look into it with my pieces and pictures. If they were mass produced like stoppers then the same shape might appear on several different manufacturers making that feature misleading for identification
Jericho, unlike stoppers, which only require some cold work to match them up to a decanter neck after the decanters are annealed and cooled, finials and other "parts" applied to hot glass need to be made at the time of the piece's production. This is to assure that the two parts are at similar temperatures.
In order to stabilize glass and reduce the possibility of it fracturing easily, it is necessary to anneal it. Annealing is the process of controlling the rate at which it cools. The annealing process prevents glass from fracturing from cooling too quickly and becoming unstable. In simple terms it reduces internal pressures and stresses found in cooling glass.
Items such as the finials would need to be applied to hot glass during production, so if pre-made it would be necessary to heat it up to a near matching temperature in order to apply it to a hot "top". In doing so, it would likely cause many pieces to crack when re-heated, so any benefit of pre-manufacturing a part for use in hot glass would be offset by damage and loss trying to reheat them to use.
Applying an unheated part to a hot part would shatter the cold glass, and even if applied successfully without it shattering, you would likely have internal cracks, commonly referred to as 'heat checks" which would appear as the two parts cooled.
You never put hot water in a cold vase to wash it...... think what applying a cool part to a hot part would do it it.
Glass melts at about 2400 degrees F, and most blowing is done in about the 1600-1900 degree F range. Annealing of glass is generally done in a 7-800 degree range.
So imagine applying a pre-made piece of cold (or even cooler glass) glass to a 1700 degree part.....
The disparity between the contraction rate of a hot part and a cold or less heated part causes stress cracks to appear in the areas where they connect. This is the reason that one occasionally sees internal cracks on applied handles and rigaree on some pieces of glass, but no cracks appear at the surface.
Finials like the black one were likely just pressed in a small mold, cut off and applied while still hot to the top of the piece in production. That would be a much simpler and more efficient manufacturing process. Is it possible there was a common tool used by different houses.... sure... That is why a finial design should only be a portion of an attribution.... one of many pointers used in the process of arriving at a conclusion.
A pedestal base, such as the ones used to support bowls that are a separate piece could be made as a separate item. Black pedestals and feet applied to hot glass as part of the piece, would need to be produced at the same time as the piece also.
Gaffers would work in groups to produce parts.... as a team... each making a component necessary to produce the desired piece.
Hope this helps to clarify.
If you want to believe that someone made finials in advance, then annealed them, stored them and then reheated them to apply to hot glass... be my guest.....
For what it is worth, you can make a finial from molten glass and apply it during production much faster than you can reheat a pre-made finial without damaging the cold glass part, to apply it to a 1700 degree object.
But like I said... Believe what you want....
GREAT explanation of the science of the process craig!
Speed of production, ease, and cost benefit; all point to your conclusion.
scott
Craig you know more about welz than anyone. I do think that simple finial was applied and not prefab, I stand corrected. On the issue of pre-formed pieces I think there are some supplied that were preformed like threading, canes and glass lozenges etc... I used to use finials as a form of identifications but they are as unrealizable as foot types. Lisa, I saw a tool in the Lenora museum that creates the foot, I'll attempt to draw it in a future post comparing the kralik foot to the Ruckl foot
Jericho, My discussion regarding the finials, would also include flowers, feet, rigaree, handles etc. Also, It is a broad general glass topic, and not a Welz specific topic at all.
My discussion is not only about glass production as such. It is as much about the physical properties of glass. There are certain things you can and can not do with the material.
Canes and lozenges are prefabbed. That is done in order to produce pieces with a symmetry and designed pattern to them. Small slices of cane can be used in a decor where the glass is remelted and blown as we see in Kralik production as well as other production, where the canes are applied to the surface of a molten gather and then reheated to be manipulated as part of the gather.
You also find concentrations of canes used in things like the bases of paperweights, and vases and lamps such as Italian Milllifiori work etc. In those cases the canes are grouped and reheated to an almost molten state to be used in production. Again, in these cases, the canes are applied to a gather of molten glass and manipulated after reheating more.
Threading is something that is pulled from a gather of glass and spun onto the surface of a vase. In some cases the threading is hand spun, such as Chiné and similar random surface threading. Most snake style threading is also hand applied from a molten gather. In other cases, such as we see in some English and Czech glass, the threading is done by machine. Hodgett, Richardson& Sons patented the first threading machine in 1876 in England. Even in those cases, the threading is molten glass and applied to a hot object in production.
Personally, I am of the opinion that a fairly comprehensive understanding of glass production techniques and processes is a critical component of the foundation necessary for an in depth understanding of glass houses and their production.
Bloody lovely mate!!
I love them all Kralik, but the first one really stands out to me... great color, the stripes, the contrasting finial and just a kiss of spatter... very nice piece!