Re: what is the right psi for zodiac futura mark1
I used to aim for 3 or 4 lbs. As the boat heats in the sun or cools in the evening, you'll probably adjust accordingly. The tubes should feel firm and harder than one might think is normal. "drum tight" is a term I heard years ago. When you sit on the tube, it should deflect just a small amount.
Filling the tubes is a process. Start with any one of them, and fill until it has nearly the proper shape, then move to the other tubes and do the same. Repeat the process until all the tubes are firm. This process results in all the chambers sharing equal pressure, and the hidden, airtight chamber dividers retain the proper, natural shape. If you filled just one chamber completely, the boat's chambers would be unable to "spread the load" in the event of a minor leak or temperature adjustment, and the boat may be slightly misshaped.
I'm sure there are better methods, but this has worked well for me.
Larry