I have acute allergic reaction to epoxy resins so I can't use them when combined as twin pack, nor any foam making agent so that rules out many products.
I tend to stick to traditional methods, many which have been forgotten about in today's technological age and money making scams.
You can all waste your money on the latest whizzo stick.
I use only ca for pens, for larger stuff I use cascamite powder, I buy it by the kilo, lasts forever if kept dry.
For filler I mix sawdust or talcum powder with it, dries overnight for turning and cures as it ages.
It has held galleons together for centuries. If it was good enough for ship builders of old it's still good enough for me. and cheap.
How to Apply Cascamite