The smelting of metals
Fusion is an integral and fundamental part of our production cycle. Just as since the 4th millennium BC, we make objects by pouring molten metal into molds. In particular, the technique we use is ground casting or also called stirrup, where the model is imprinted on special grounds beaten inside the steel stirrups.
Technical description
The stirrup casting allows the re-use of the matrices: the model, which must be made of consistent material, is inserted into a “stirrup” made up of two connectable steel frames; in this frame the refractory ground is appreciated, obtaining the negative shape of the model to be reproduced. The material is then removed and in the formed cavity – and through the previously prepared inlet channels – the molten metal is thrown, which will fill all the empty spaces.
This technique is mainly used with low relief models without undercut. But it is still applicable – even if with greater difficulty and great skill – to high reliefs; in this case, the shaping is carried out by creating anchors always in the ground, positioned and fixed by metal pins in the undercut points.
One of the oldest systems is the fusion with cuttlefish bone: this material in fact behaves like refractory ground, maintaining the shape of the model without undercuts, without immediately burning even in contact with the high temperature of the molten metal.
The smelting of metals
Fusion is an integral and fundamental part of our production cycle. Just as since the 4th millennium BC, we make objects by pouring molten metal into molds. In particular, the technique we use is ground casting or also called stirrup, where the model is imprinted on special grounds beaten inside the steel stirrups.
Technical description
The stirrup casting allows the re-use of the matrices: the model, which must be made of consistent material, is inserted into a “stirrup” made up of two connectable steel frames; in this frame the refractory ground is appreciated, obtaining the negative shape of the model to be reproduced. The material is then removed and in the formed cavity – and through the previously prepared inlet channels – the molten metal is thrown, which will fill all the empty spaces.
This technique is mainly used with low relief models without undercut. But it is still applicable – even if with greater difficulty and great skill – to high reliefs; in this case, the shaping is carried out by creating anchors always in the ground, positioned and fixed by metal pins in the undercut points.
One of the oldest systems is the fusion with cuttlefish bone: this material in fact behaves like refractory ground, maintaining the shape of the model without undercuts, without immediately burning even in contact with the high temperature of the molten metal.
Techniques and Processing
Each metal has a different soul
For many years, in Marco Riccardi’s laboratory, we have been creating objects with a refined design, using the best known processing techniques: both for bronze and copper, passing through brass and steel.
Techniques vary and are distinguished not only by the metal chosen, but also according to the effect you want to reach.
Competence and experience are fundamental elements for a result that always gives great satisfaction to our customers. The best craftsmen collaborate with us, for an impeccable and highly aesthetic work.
These are the main phases:
- Creation of the model
- Creation of the mold
- Baking of the mold (with the model that is lost or is extracted first)
- Casting of molten bronze
- Finishing
Practically, the bronze is melted and poured into a mold, of which it takes the shape by solidifying. Extracted from the mold, it is processed and cold finished.
What differs in the various techniques is the material that constitutes the mold and the model, which, depending on its composition, can be stored and reused or destroyed during the cooking of the mold. This is the case of the lost wax technique , very common in antiquity, in which the model was made of wax and covered with refractory material, usually clay. In the oven, the clay cooked solidifying, while the wax melts and disperses. The bronze was then poured into the mold.
Once cooled, the clay was extracted and finished. In this case, both model and mold were destroyed. In other situations, however, such as in sand casting techniques, the model is extracted before starting the casting, keeping it for subsequent copies. After processing, it is also possible to embellish the design object by applying galvanic and chemical surface treatments, including: gilding, nickel plating, chrome plating, silver plating, burnishing and bronzing.
• Choice of type and size of the brass profiles , to be used in relation to the technical specifications of the production from
• Cutting : the profiles are cut to size using a miter saw, following the design indications
• Bending : the profiles are modeled using a "pipe bender", or by hand using fire.
• Drilling : some profiles are subjected to drilling using an electric drill;
• Milling and turning : metal swarf removal operations that exploit the rotary motion of the tool and the piece
• Smerigliatura: per predisporre i profili alle successive fasi di lavorazione (saldatura, assemblaggio, lucidatura)
• Welding : the materials are assembled on special work benches by welding with the technique of brazing with support material in silver alloy, or tin welding
• Grinding : this further phase eliminates any imperfections deriving from the welding phase and its cleaning
• Cleaning : any slag left by the previous processing steps is eliminated
•Realization of accessories and small finishes to be carried out directly on the final product
• Final assembly of accessories and profiles
After processing, it is finally possible to enrich the design object by applying galvanic and chemical treatments to the surface, such as: gilding, nickel plating, chrome plating, silver plating, burnishing and bronzing.
One of the most used techniques is copper engraving and embossing, and is divided into:
• Engraving : drawing a composition with pressure on a thin copper sheet, then proceeding with the embossing (embossing) of the parts to be embossed. The slab, when pressed with special tools both in front and behind, is transformed into a bas-relief sculpture
• Consolidation : once the three-dimensional slab has been obtained, we proceed with the framework, consolidation of the low relief through a wooden support structure, so as to obtain the desired artefact
• Patination : the object is ready for the last step, which has the task of giving it a "naturally" artificial coloring through the use of (non-toxic) acids. The final effect is a bronze bas-relief, more or less burnished
• To give copper and its alloys the desired color and appearance, chemical treatments are used, which stimulate the aging , accelerating the copper transformation process. Using the same brass techniques you can also make furnishing objects, such as chandeliers, wall lamps, lanterns and other design creations.
• After processing, it is also possible to embellish the design object by applying galvanic and chemical surface treatments , such as: gilding, nickel plating, chrome plating, silver plating, burnishing and bronzing.
The processing of metal materials, generally, means starting from "semi-finished": blocks of different shapes and sizes which then, through the various processing techniques, acquire the desired lines and dimensions. The main processing techniques that can be used to model steel are:
• Cutting : using abrasive wheels or shears;
• Molding : gives a shape to the semi-finished product using machines equipped with a "female" mold (cavity that our steel must reproduce) and "male" mold (which presses on the semi-finished product, so it fills the female mold and acquires its shape)
• Bending : useful for making a sheet
• Milling and turning : metal swarf removal operations that exploit the rotary motion of the tool and the piece
• Welding : joins several parts by melting the steel at the junction point of the different parts.
Techniques to work with bronze are numerous. Mainly they refer to the ancient method of casting in negative mold, still used today, albeit with the necessary technological adaptations.
Over time, new materials have been introduced; among these polystyrene, silicone and thermosetting resins. But the technique remains essentially unchanged.
These are the main phases:
- Creation of the model
- Creation of the mold
- Baking of the mold (with the model that is lost or is extracted first)
- Casting of molten bronze
- Finishing
Practically, the bronze is melted and poured into a mold, of which it takes the shape by solidifying. Extracted from the mold, it is processed and cold finished.
What differs in the various techniques is the material that constitutes the mold and the model, which, depending on its composition, can be stored and reused or destroyed during the cooking of the mold.
This is the case of the lost wax technique , very common in antiquity, in which the model was made of wax and covered with refractory material, usually clay. In the oven, the clay cooked solidifying, while the wax melts and disperses. The bronze was then poured into the mold.
Once cooled, the clay was extracted and finished. In this case, both model and mold were destroyed.
In other situations, however, such as in sand casting techniques, the model is extracted before starting the casting, keeping it for subsequent copies. After processing, it is also possible to embellish the design object by applying galvanic and chemical surface treatments, including: gilding, nickel plating, chrome plating, silver plating, burnishing and bronzing.
The brass production cycle takes place following accurate and distinct phases which, with their own unique value and technique, lead to the creation of the final product.
Here are all the steps involved:
- Choice of type and size of the brass profiles , to be used in relation to the technical specifications of the production from
- Cutting : the profiles are cut to size using a miter saw, following the design indications
- Bending : the profiles are modeled using a “pipe bender”, or by hand using fire.
- Drilling : some profiles are subjected to drilling using an electric drill;
- Milling and turning : metal swarf removal operations that exploit the rotary motion of the tool and the piece
- Smerigliatura: per predisporre i profili alle successive fasi di lavorazione (saldatura, assemblaggio, lucidatura)
- Welding : the materials are assembled on special work benches by welding with the technique of brazing with support material in silver alloy, or tin welding
- Grinding : this further phase eliminates any imperfections deriving from the welding phase and its cleaning
- Cleaning : any slag left by the previous processing steps is eliminated
- Realization of accessories and small finishes to be carried out directly on the final product
- Final assembly of accessories and profiles
After processing, it is finally possible to enrich the design object by applying galvanic and chemical treatments to the surface, such as: gilding, nickel plating, chrome plating, silver plating, burnishing and bronzing.
Working of copper dates back to prehistoric times: the oldest known copper object is a small pendant obtained from the unworked mineral, discovered in the Shanidar cave in Kurdistan and dating back to 12,000 years ago. In Italy we have the first traces of its use only a few millennia later, starting from 4,000 BC. We are talking about one of the oldest metalworkings that have existed and that our craftsmen continue to carry out with passion and competence, always renewed.
One of the most used techniques is copper engraving and embossing, and is divided into:
- Engraving : drawing a composition with pressure on a thin copper sheet, then proceeding with the embossing (embossing) of the parts to be embossed. The slab, when pressed with special tools both in front and behind, is transformed into a bas-relief sculpture
- Consolidation : once the three-dimensional slab has been obtained, we proceed with the framework, consolidation of the low relief through a wooden support structure, so as to obtain the desired artefact
- Patination : the object is ready for the last step, which has the task of giving it a “naturally” artificial coloring through the use of (non-toxic) acids. The final effect is a bronze bas-relief, more or less burnished
- To give copper and its alloys the desired color and appearance, chemical treatments are used, which stimulate the aging , accelerating the copper transformation process. Using the same brass techniques you can also make furnishing objects, such as chandeliers, wall lamps, lanterns and other design creations.
- After processing, it is also possible to embellish the design object by applying galvanic and chemical surface treatments , such as: gilding, nickel plating, chrome plating, silver plating, burnishing and bronzing.
Starting from the best semi-finished products available on market, our technologies allow us to perform with extreme precision all the phases of steel processing for the creation of the most sophisticated design objects. Human resources enrich the work, thanks to the every day professionalism and innovations involved in designing the final products.
The processing of metal materials, generally, means starting from “semi-finished”: blocks of different shapes and sizes which then, through the various processing techniques, acquire the desired lines and dimensions. The main processing techniques that can be used to model steel are:
- Cutting : using abrasive wheels or shears;
- Molding : gives a shape to the semi-finished product using machines equipped with a “female” mold (cavity that our steel must reproduce) and “male” mold (which presses on the semi-finished product, so it fills the female mold and acquires its shape)
- Bending : useful for making a sheet
- Milling and turning : metal swarf removal operations that exploit the rotary motion of the tool and the piece
- Welding : joins several parts by melting the steel at the junction point of the different parts.