Traud - That looks good. 40psi is more than enough pressure. My pot is rated @ 80psi like yours. But, there is no need to go that high. 80psi would be over kill and extra wear on the pot too. Most of these come with a straight pipe on the inside that leads down to the bottom of the pot. I discarded mine and replaced it with an elbow connector. This way the air flow doesn't shoot straight down into the pot: and blow your resin right out of your molds. You can also place some wooden blocks inside the pot to take up space if your are casting a couple small molds: less space in the pot = less air needed to fill it up.

The main thing is TO BECAREFUL.
Bob