[Peter whiteley]

Hi.
Strange question , I’m looking for the best way to ensure a clear cast polyester resin will crack as much as possible. The piece will be approx 15-20 cm at it’s thickest point .
IT will be cast in a silicon mold over a release agent for easy removal, bust I need the piece to crack to give the effect I need .
Thanks in advance.
Peter.

[Katherine Swift]

Hi Peter,

Add in more hardener than is suggested. That will cause the resin to heat up too much and crack.

[Nellie Rodriguez]

Hi, how much more hardener should be added to achieve the crackle effect?

[Katherine Swift]

If you warm the resin up too, that will help. Maybe try 25% more than what is recommended and go from there.

[Ranjit]

I’ve tried adding extra hardner to polyester resin and extra heat that it generates does indeed crack the resin but, there is no controlling the process once it starts, the number of cracks, the depth of the crack and the location of the cracks all depend on the design and the temperature.
Once the resin heats up it hardens really fast and may have surface undulations due to the uneven heating, you can also drop the resin piece into cold water at this point to induce cracking. As I have observed, there is no control over the process once it starts.
That said, every cracked piece you make will be unique.

[Author]

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