Hi George
How's things...? Nice to see you've got things on the go - when did you start...?
On the Ciment Fondu thing, I'm a bit surprised you need 100kg ! That would indicate needing around 400kg of Sand, which would be a lot of mortar ! The page here
Ciment FonduŽ gives you and idea of the mix.
Interestingly, ciment fondu is banned for building use in some countries - it becomes porous over a period of time and weakens. Not sure if I'd want to trust my dome to that !
There have been a few queries about what to put in instead of the fireclay - a standard mortar mix may work, but as I've still got the dome to do, I'm probably not the one to say !
Need to catch up for a beer sometime
Cheers
Peter