How casting surface finish can be improved with two part sand as well as CO2 sand ? Suggest sand properties, Proportions of mixtures & Paint to be used for painting the mould etc. so that we can get spotless casting with superb finish.
In sand casting practice it is very difficult to achieve spotless casting especially when you are processing steel castings. This is due to the metal mould reaction and alsop the high temperature of pouring involved. Ready made zircon mould coats are supplied by the foundry chemical manufacturers. You may try from Foseco who have good products or ask their service engineer for application related doubts.