Slush Casting for Hollow Objects

Mold making is a wide-ranging art form which invokes varied materials as well as techniques. The choice of mold making procedure depends as much on the model as the skill and dexterity of the mold maker. So is the case for the mold making materials.

The simplest form of mold is a block mold where you simply pour the mold making material over the object or statue to be replicated. Intricate shapes may require the mold to be made in two or even more parts. More complex techniques range from blanket molds and glove molds to injection molds and more.

And once the mold is ready, the artist moves on to making the final cast from the mold. Again, the choice of the techniques and materials varies from artist to artist and application to application.

A lesser known technique of making casts is the slush casting. This is a traditional method of permanent mold casting wherein the liquid casting material is not allowed to completely solidify in the mold. Once the desired thickness is obtained, the remaining material is simply poured out.

This technique comes in handy for casting hollow items such as toys, decorative pieces, statues, ornaments, components, etc.

The procedure is pretty simple in fact. The mold is placed on a flat surface so that the opening is on the top. The casting material is slowly poured into the mold opening. This could be clay slip, liquid latex rubber, molten metal (usually zinc, tin or aluminum) or even something else. The mold should be rotated a bit so that the material swirls around and completely coats the sides and bottom.

Once the material starts cooling or setting in the mold, it is turned over and the remaining material is poured out of the mold. A thin skin is left behind and this will solidify to form the hollow cast.

To form a thicker shell, the casting material simply needs to be left in the mold for a longer period. Alternatively, if the cast seems to be too thin, the pouring in and out process is repeated until the desired thickness is built up.

The cast is then removed and allowed to set properly. The cast will turn out accurate and have a smooth outer finish as well. As it is hollow, the cast is definitely much lighter than a solid metal or clay object would be.

Slush casting is usually used to make decorative bowls, vases, lamp bases, candlesticks, miniatures and so on, without the use of cores. The same process is successfully adapted to create a latex mask and other thin skin latex products as well. Cosplay costumes, props and even helmets are made using similar techniques.

Playing With the Cure Time of Molds and Casts

Every mold making and casting material comes with its own specific range of cure time. This is nothing but the time that the material will take to get completely cured. It can range from just a few minutes to hours or even a few days. The mold or cast has to be left to air dry on its own and there is nothing much that the artist can do in the meanwhile.

Similarly, the pot time or working time is the time on hand to work with the product after it is mixed until it starts to set. After this, the material will not work properly.

For instance, alginate is renowned for its quick setting and curing time, whereas materials like latex rubber require days on end to cure before they are ready for use. Most silicones have a cure time between 18 to 24 hours.

What to do?

Artists use various measures to speed up or prolong the cure time. In fact, delayed-setting and quick curing options are available for alginates, plasters, silicone and other materials. Sometimes, fibers, fillers, talc or magnesium oxide (for plaster) are added to achieve the same effect.

For certain materials like silicone, fast catalysts are also available. These can be added to the silicone rubber to significantly reduce the cure time, sometimes to even just an hour! Care is needed as adding too much catalyst may make the material start curing even before it can be applied.

Alternatively, techniques like hot air dryer, dehumidifier or baking in an oven are used to hasten the cure time. In fact, plaster casts are often baked to reduce the curing time to 12 to 24 hours. However, too much of the hot air can also cause the mold or cast to crack or spall. Also, silicone does not react very well to heating from dryers or lamps; it may just break out in unsightly bubbles all over the mold or cast.

Temperature variation

It should be noted that the pot time and cure time is generally measured at normal room temperature. It will definitely vary depending on the atmospheric and climatic conditions prevailing at the time of working/curing. For instance, cooler temperatures tend to increase the pot time and cure time while warmer weather is sure to reduce both working time and cure time.

This phenomenon can be easily used to vary the pot/cure time to suit your convenience when trying how to make molds. All you have to do is gently warm the material (both base and catalyst for two-part materials) before using them. This will speed up the chemical reaction and the mold or cast will take lesser time to cure. But keep in mind that the working time is also reduced and the material will start setting much more quickly. Do not overheat the materials either.

Similarly, cure time can be easily increased by refrigerating the material (both base and catalyst again) prior to use of how to make molds. This will give more time for working with the material per se.

A Look Into GUIDI

An unprecedented devotion to artistry along with an uncanny revere for its ancestry accurately describes the craftsmanship of the fashion house: Guidi. Founded in 1896, Guido Guidi, Giovanni Rosellini, and Gino Ulivo would later establish Conceria Guidi Rosellini, Italian for “Guidi-Rosellini Tannery” (Guidi, n.d.). In doing so, the trio managed revolutionize the mask of an artisan good that currently serves as the very nucleus of fashion, leather. This proved to be an honorable feat, with respect to the location of the settlement being Tuscany, a region in central Italy in which leather tanneries dates back to the middle ages.

Such an intrinsic connection to the manufacturing of leather products relies upon a keen understanding of the many kinds of leather, their individualistic properties, and the most advantageous mechanisms in which they are produced. Guidi, rebukes the ideology known as mass production, substituting the convenient mechanism for a more organic approach, mandating that all products be completely made by hand, with no products serving as a duplicate of another, which explains why the production of these products is masterfully elongated to ensure the cultivation of an optimal product is established and transparent.

The first step to the process of the leather based treasuries is the fleshing of the respective mammal, ensuring that an optimal amount of thickness is achieved, Guidi allows themselves three to five days to soften the skin using a pre-historic hand-tool, known as a “palmella”, followed by the use of similar glass and stone based tools used for purposes of greasing. As soon as the skin is palpably favored, the skins are, tanned, dyed, and dried separately. Every step must be undergone before Guidi is to offer an item such as the Guidi 988 boots (currently being sold for nearly $1100 USD), where the outer portion of the shoe’s upper body and lining of were constructed with the same single piece of 100% horse leather (Farfetch, n.d.). A notable feature of Guidi products is ‘transpiration’, which offers a prime level of comfort and durability for those actually wearing the leather throughout any season of the year, ensuring the user to get a considerable amount of use for the product in the summer as well as the winter. However, Guidi universally accommodates to the needs of its owner, beautifully epitomizing the concept of consumerism.

Presently, the creative director of the brand is Ruggero Guidi. Ruggero has successfully sustained the legacy of his predecessors with his inherited enslavement to divineness. Much of this due to his obsession for supreme leathers and regard for the family name, infused with an inclination to expand upon the mantle handed to him. He is in constant search for a compromise between technological advancements while utilizing the fundamentals of tannery. Ruggero stands as the leather tanner that the most demanding fashion designers around the world aspire to collaborate with. Whether it’s polishing the raw materials, or the dying of shoes as they tumble. Guidi constructs items to display the degree of quality of the items used in its work-a multitude of soft, delicately layered, pleasantly scented hides, tailored for enthusiasts seeking exclusivity in products that can only be crafted by the few.

“The art of the tan” is a mantra often echoed throughout the history of the brand, reflecting the chronic implementation of the grace of its forefathers amidst the integration of modernization Guidi is the personification of luxury and tradition, focusing on independently conducted research to solidify that each piece is distinctively characterized for the sole use of its rightful owner.