Silicone Hardness

[mangozac]

Hi all,

I'm on the hunt for a new silicone product. The one that I have been using is a Shore A 20 hardness, which is actually quite soft. So I figured I'd ask what the hardness of the silicones you guys were using are. For the record the application is generally single part split moulds (which generally need to be a little more flexible than multi-part moulds).

Please post the silicone you use, its hardness and how you find its flexibility. I'll compile it all in a table here for future reference

[Fleafa]

I was using . It was great, but had some problems being used soon after curing with Smooth-Cast 305. A slow cure, but wasn't a problem for me. UK only, I think.
Currently trying . It is fine, though a little too soft if I lower the viscosity. Went with it as it is cheaper than the opaque plat-cure, which only comes in 15/16A or 30A. The speed of cure is great. US and UK?

[mangozac]

Very interesting. 15/16A sounds quite soft and 30A seems to be getting fairly high for our kind of moulding. I think the 20-25A seems to be a really nice range, but the product I'm looking at is 28A. I'm sure it will be fine but I'm just trying to get a feel for it. Probably going to push the button on a 1kg sample pack this week to try it out. 90+ minutes of pot life means I can degas it for ages!

[Fleafa]

28A with would drop that down to the sweet spot (24A @5%, 21.5A @10%) whilst dropping the viscosity (75% and 55% respectively).

[mangozac]

[Fleafa]

[mangozac]