Thanks Arwyn, I was thinking of that. Do you squeeze it in and then let it set up inside the ring before putting back together?
A tip when using sealant to form a gasket learnt from my yotty years. Apply generously then clamp item down gently wiping off excess. Wait at least 24 hours to go off then tighten fully. This saves all the sealant being squeezed out at first application.
