getho reflector

I jus got a 600w hps and forgot the reflector so all i have is a light socket hanging off a wire. How hot do these bulbs get? I was thinking of making a reflector out of plywood, but i don't want to set my shit on fire. Saw a thread where a guy made one out of a mailbox, but some other dude said it was gonna fry his balast electrocute him and set his house on fire, I'd rather not have my reflector do that kinda stuff. So anyone got any advice?

Sheet metal works pretty well.