Brushing cast & Perfusion Molding operation of Silicone rubber

Brushing cast & Perfusion Molding operation of Silicone rubber 

Brushing cast:

a. Evenly brush the mixed silicon rubber on the product which is covered with mold spray with a brush or a brush pen.

b. After the cross linking reaction (about 30 minutes), brush a second coat which can increase the tension and tear strength of the mold.

c. Cover a glass cloth on it after another 30 minutes of a second cross linking reaction, and use a brush pen or a brush to avoid any interstices.

d. Cover a third coat.

(Note: if you have high requirements for the tension and the tear strength for the mold, please repeat step c and step d. Hence, the finished silicone moulds will have a good quality and a longer life, which can help you save cost and increase production efficiency.)

Perfusion moulding:

It is suitable for simple products with the smooth surface.Without any mold lines,which helps you save time and is easy for operation.Evenly and slowly perfuse the mixed silicone rubber into the square fram.After the cross linking reaction and the silicone rubber turns dry,you can take the products out.Thus,the mold has been done.

(Note:we usaully use soft silicone rubber to make molds by perfusing,which is easy for demoulding and will not damage the product in the silicone molds.)

 FAQ of moulding silicone rubber

1. Why could the silicone mold be reused only for a few times?

It can be due to the following reasons:

a. Adding too much silicone oil in to silicon rubber. Silicon oil is an additive which destroies the molecular weight of silicone rubber and reduce the tension and tear strength.

b. Using the silicon rubber with a high hardness to make molds for small sized products with delicate and intricate designs and the silicon rubber with a low hardness to makes molds for large sized products with simple designs.

(Notes: we should choose the silicon rubber specifically according to the requirements of our products to avoid this problem.)