Sand blast gun

Get a Gun Upgrade Kit from TPTools.com. It's got a better gun, carbide tips (ceramic ones suck), and a new pickup tube.
No one should EVER blast with sand of any kind. Read up on silicosis and you'll find out why. Further, playground sand is too soft to cut well and it pulverizes into dust much faster. Get some real media instead. There are dozens of media blasting discussions on the internet -- try The Garage Journal for a great start and to learn what each does best.