The work is impressive paul n thanks for the link. The space needs a regulator ?

A dam bead n receiver gasket is in order.

McMaster Carr lists 1/2" nitrile with 1/16th" wall maybe EOM on the Solstice but not 1/16th" in wider tubing only 1/8th"

Ordered 1/16th replacement tubing and a length of wider 1/8th trying as either a bed for the 1/16th or now, with a bead.

The other option there is a silicone nitrile at $50/hatch. Local noise has it that this tubing was without an appreciable difference in tightness.

The NB sneakers are possibly use able over time with 847. The sole's sides look good, but not proven, and are EPDM not nitrile ?

Hatch leakage and a cure are my operation not CD's design tho a better gasket is in order.

The Solstice rolls quickly with a snap float assisted practice roll without expertise as I am not. Load is 70% ? touring with 30 liters water in MSR 10L Dromedary bags velcroed to the inside hull keel line, one front hatch, two rear with two more inside cockpit planned.

There's a photo at SEA KAYAKER FORUMS.

BTW, for training a 2 float paddle works right off. There's an NRS inflatable and a solid foam rectangular float for the frozen fingers group.

In two short sessions, leaning my ear down at the water then applying hip snap practice with Ford's animated twist into snap visualization, produced a perfect snap roll. OUTASIGHT !

Then I jammed my back agaiunst the coaming with a layback move....