Igor-
You would have to find a foundry supplier that would be willing to sell small quantities of resin binder, which I think is probably not realistic.
Some have experimented with using epoxy as a resin binder, but I have not tried that, and don't know how successful it may be.
Alternately sodium silicate can be used to make both cores and molds, and it seems to be much more readily available, since it is used by pottery makers, and for other purposes.
I would probaby look for sodium silicate first, since it is relatively inexpensive, is much less toxic than resin, and much more available.
Sodium silicate can be hardened with CO2, or a catalyst if you can find that.
.
You would have to find a foundry supplier that would be willing to sell small quantities of resin binder, which I think is probably not realistic.
Some have experimented with using epoxy as a resin binder, but I have not tried that, and don't know how successful it may be.
Alternately sodium silicate can be used to make both cores and molds, and it seems to be much more readily available, since it is used by pottery makers, and for other purposes.
I would probaby look for sodium silicate first, since it is relatively inexpensive, is much less toxic than resin, and much more available.
Sodium silicate can be hardened with CO2, or a catalyst if you can find that.
.