silicone heat pad curing

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#1

Hello everyone,

I have a project to make a product that requires relatively high temperature cures but unfortunately it does not lend itself to be cured in an autoclave or oven so im looking to cure using some sort of heat blanket or silicone pads.

Im wondering if anyone has done cures using this method before and what are the pros and cons to watch out for?

As the part will be cured using heat pads at 200 degreesC in a room at ambient, is there issues to watch out for with the moulds being heated from one side, and whats the best side to apply heat, through the back of the mould for heat transfer onto the tool face or onto the back of the laminate stack?

I would really enjoy hearing your thoughts guys and hopefully i can get some clarity from someone who has already trialled this…

cheers

#2

How big is the part?

Your enemy is heat loss. You will probably find yourself heating from both sides. Is your mould suitable for 200C?

Thermal shock is also an issue, as well as uneven heating.

#3

Hello,

Parts are relatively large (600mm wide x 700mm long x 500mm high). My concerns were getting even heat transfer because if the entire parts were not covered (and it will be relatively difficult to do this due to shape) it would sap heat and become uneven and alittle more tricky to gauge. I did consider thermal shock and as this is a production mould i was worried that the lifespan would be reduced Vs building an oven. I have looked at the coating systems you listed on another post that heat up when electricity is passed? Are these a potential candidate for this situation? as heat will be more uniform and i assume thermal shock could be reduced as the tool could be brought back to ambient at a more controlled rate?

Curing with these types of processes seem to be over complicating a matter… My thoughts are now drifting towards building a bespoke oven because it seems just too problematic otherwise.

Thanks for your input, much appreciated.