I wasn't so impressed with the shape of the mould, so I decided to reshape the plug and vacuum bag the layup over that instead. I started by hollowing out the underside with the die grinder to accommodate the antenna base, then I laid the plug in a bed of moulding wax to hold the vacuum. Then I applied release wax, PVA, release tape, perimeter tape, glassed on five layers of 200gsm, a layer of peel ply and breather cloth then closed it off wth the bagging film ready for the vacuum. It looks like this will work out much better.
