I mentioned that I was trying to make Milestag acrylic domes to my neighbour who reminded me that he was a pattern maker and with a 'leave it with me' off he went.
Today he turned up with these:
6 dome moulds with a 3 degrees draft angle. All I need to do is fasten them to some plywood (supplied) and drill some forming holes.
They are made of a wierd material made from a composite of Welsh slate and resin.
Can't wait to try them.....