Q: Why is special equipment necessary to blast with soda? How does soda blasting equipment differ from sand blasting equipment?
A: It differs in several different ways but the main difference/problems have been "flow" and "caking"; inconsistient pressure for flow coupled with the fact that Bicarbonate of soda absorbs moisture and then cakes at the bottom of standard pressure blaster units. (i.e.: ALC, CLARKE, et al.)
Q. What are the conversion part(s) from Eastwood? Can this be duplicated from parts obtained at a well-stocked hardware store?
A. The conversion kit mechanism is more than, "... off-the-shelf brass fittings, valves and tubing." Hundred's upon hundred's of man hours have been devoted to engineer, design, develop, test, specially manufacture, prepare, and finally submit for U.S. Patent a product that is unique in design and function.
Bottom line: Baking Soda Media would not function in a pressure blaster until Eastwood designed specially ENGINEERED adapters. There are kits to convert ALC (R), CLARKE(R), BRUT(tm), Harbor Freight(tm), TP Tools (tm) 3/8" and 1/2" NPT fitting units to be able to blast Soda and convert back to Abrasive. PLUS you have dual functionality of being able to blast either Soda or Abrasive.
Q. Is the soda obtained from the swimming pool supply store the same material that is used for blasting?
A: Baking Soda (Bicarbonate of Soda) is a naturally occuring mineral which is mined and processed into different grits or granular thickness. Baking Soda used in Swimming Pool applications is too fine for use in abrasive blasting applications it will not remove paint effectively. This as well as household baking soda will not flow in properly and should never be used for this abrasive blasting applications.