[tavo1765]

This is a good question. I always pre heat my oven up to 400f and let it soak the heat at that temp. for 30mins. This way I know my oven is at the correct operating temp, Parts come out smoother and more uniform.

Placing parts in a cold oven allow the part to sit in longer then they are supposed to be so curing problems might occur. A part will be cured before it gets to temp because it starts to flow out when it reaches 300f, not that some colors like the ramp up, like lighter colors or clears.