04:11
Faizan
The art of life casting requires the use of skin safe products as they should not damage the model in any manner. Therefore, alginate is considered the best mold making material for taking molds from the live human body. It can capture the finest of details as well.
This alginate is similar to what dentists use to take teeth impressions from inside the mouth before making false teeth or dentures from the same. This alginate is made from the stems of brown seaweed and is therefore both food and skin safe. And it is environment friendly as well.
The chemical name of this substance is sodium alginate and should not be confused with sodium silicate which is used in making sand castings. Also keep in mind that red or green seaweeds are not useful. Only brown seaweeds can be used to derive alginate.
Alginate comes in a powder form and should be mixed with water to form a thick liquid like paste. The classic mix ratio is 1 part powder to 3 parts water and this has a slower setting time than the dental alginate. Cold water works to further slow down the setting time while hot water accelerates the same.
Alginate should be mixed thoroughly with the water (preferably with a mixer) to get a smooth consistency. You also need to mix in precise proportions for best results.
Watch Out!
It should be kept in mind that if alginate is mixed with hard water it will leave a lumpy mess that will not set properly. This is because hard water contains minerals like calcium and magnesium. So if your tap water is hard, it is better to use distilled or bottled water to get a smooth mix. Experts always advise to test a sample first before applying to your mold making project.
Alginate molds need to be reinforced with plaster bandages to form a mother mold.
A body mold made from alginate is considered as a waste molds because the water will evaporate from the mold causing it to shrink soon enough. Therefore, alginate molds should be used quickly and will last for 1 to 2 castings only. You generally have a 3 hour window for casting into the alginate mold before it starts getting distorted. On the other hand, sand molds that are made by adding sodium silicate to fine sand are pretty permanent.
The alginate available in the market generally has clay fillers added to it which imparts a firm set to the mold. Silica free alginates have also been formulated which have a soft set and are very gentle on the skin. This makes them suitable for using on infants and small children.
Another variant of alginate contains fiber which increases its tear strength manifold. This type of alginate enjoys delayed shrinkage too as it can hold moisture for a longer time.
This alginate is similar to what dentists use to take teeth impressions from inside the mouth before making false teeth or dentures from the same. This alginate is made from the stems of brown seaweed and is therefore both food and skin safe. And it is environment friendly as well.
The chemical name of this substance is sodium alginate and should not be confused with sodium silicate which is used in making sand castings. Also keep in mind that red or green seaweeds are not useful. Only brown seaweeds can be used to derive alginate.
Alginate comes in a powder form and should be mixed with water to form a thick liquid like paste. The classic mix ratio is 1 part powder to 3 parts water and this has a slower setting time than the dental alginate. Cold water works to further slow down the setting time while hot water accelerates the same.
Alginate should be mixed thoroughly with the water (preferably with a mixer) to get a smooth consistency. You also need to mix in precise proportions for best results.
Watch Out!
It should be kept in mind that if alginate is mixed with hard water it will leave a lumpy mess that will not set properly. This is because hard water contains minerals like calcium and magnesium. So if your tap water is hard, it is better to use distilled or bottled water to get a smooth mix. Experts always advise to test a sample first before applying to your mold making project.
Alginate molds need to be reinforced with plaster bandages to form a mother mold.
A body mold made from alginate is considered as a waste molds because the water will evaporate from the mold causing it to shrink soon enough. Therefore, alginate molds should be used quickly and will last for 1 to 2 castings only. You generally have a 3 hour window for casting into the alginate mold before it starts getting distorted. On the other hand, sand molds that are made by adding sodium silicate to fine sand are pretty permanent.
The alginate available in the market generally has clay fillers added to it which imparts a firm set to the mold. Silica free alginates have also been formulated which have a soft set and are very gentle on the skin. This makes them suitable for using on infants and small children.
Another variant of alginate contains fiber which increases its tear strength manifold. This type of alginate enjoys delayed shrinkage too as it can hold moisture for a longer time.
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