Answer:
Differences Between Silica sol investment casting and water glass investment castings

Silica sol and water glass are two kinds of different processes of investment castings. The cost of water glass is lower but it mainly suits for most carbon steel material products,and for the ones which is simple structure. Because if structure is complicated if by water glass then need too much later machine handle, that way increase cost instead.
Different adhesives are used, one is water glass and the other is silica sol. The shell mold is not the same for drying and hardening. Water glass uses a hardening agent such as ammonium chloride, while the silica sol shell mold is dried and hardened in a constant temperature and humidity space.
In addition to the surface smoothness and accuracy, the silica sol molding process is higher than water glass.
How many sets molds does it need for manufacturing one model stainless steel castings?
Normally one set is enough, according to dimension of castings, the artificial wax casting machine can make 1 or 2 or 4 pieces wax castings at one time. The automatic wax casting machine can come out 8-9 pieces wax castings at one time, it is faster, meanwhile its cost is a little higher.
Normally one wax casting machine make one products.