thanks... i went and read the can and it says right on there (imagine that?). got to wait 20-30 minuets at 70*, so i'll give it an hour since its a bit colder and more humid out.
as for the brand... i've never heard of it before, its what the store sold me to work with their dupont paint that i bought. its just a normal build primer.
Get the technical datasheet for this particular primer; it will tell you when to apply a topcoat (usually after one hour and before 24 hours) or when you can sand (high build primers typically take 2 hours).
Well, you've gotten good advise form the others. Traditional primers are designed to be top coated within 24 hours; however, some of the newer epoxy primers expand this window to allow up to 72 hours. The technical sheets (if not given on the can) will properly identify recommended top coating times for the best results.