Thanks for your help!
What is "glue strength filler"? Do you mean epoxy mixed so it's not very runny? Or some other product?
How much epoxy does one use in a repair? I realise that's a "how long is a piece of string" question, but I see the stuff comes in quantities from 200ml or so to several litres. I have to repair a crack that is around 10cm long, obviously going well beyond that length in all directions to make sure the repair is strong. I was looking at this product, which claims to be flexible, which I think is a good thing given the location of the crack. This "kit" has 250ml in total, would that be likely to be enough?
www.theboatwarehouse.com.au/boat-building-maintenance/epoxy-resins-hardeners-glues-fillers/west-system-g-flex-650-epoxy-kit-250ml/(obviously can buy more, but the stuff isn't cheap, ...)
If I was choosing an epoxy with fast/slow hardner options (the Norglass have those), what would best suit repairs done in about 20-25 degrees C?