Before trying to print my own soap molds, I need to identify what characteristics I like in a mold. I find flexible molds easier to work with than rigid ones – I’ve snapped a number of molds trying to remove the soap.

So I am trying to find a material that will withstand heat generated by saponification. It looks like saponification can yield temperatures up to 88° C. I don’t want to buy pounds of different filaments to test them out, but GlobalFSD offers “sample” size filament cuttings that are perfect for experimentation or small niche products (e.g. printing glow in the dark mailbox numbers).

One material included information about temps for printed objects, so I’ve contacted the other manufacturers to see if they provide any sort of guidance.

Material	Max C	Min C	Notes	URL
NinjaFlex	65.5	-30		https://www.globalfsdusa.com/ninjaflex-by-fenner-drives.html?category_id=20
CrystalFlex	–	–	Food safe	https://www.globalfsdusa.com/crystalflex-tm-by-formfutura.html?category_id=20
FilaFlex				https://www.globalfsdusa.com/filaflex-by-recreus-1-75mm.html?category_id=20
FlexFill	230	-40		https://www.globalfsdusa.com/flexfil-98a-by-fillamentum-1-75mm.html?category_id=20
F41 Flex	75	-20		https://www.globalfsdusa.com/f41-flex-tm-1-75mm-black-polyolefin-filament-by-forefront.html?category_id=20