[cdowns]

i use blasting sand it is well graded and sterile and has a far sharper cutting edge than "play sand"

play sand in many places is stored outside in the rain and is full of moisture, as well as not being that finly grated and depending on where and how it was mined can have minerals in it like salt that effect your longterm result

the brain surgen my brither in law couldnt see the need for "buyin" sand he just went to the beach and helped himself to a truck full when he was restoring a 58 chevy needless to say it rusted to the groud in 18months after being blasted to bare metal with that ocean sand