Large mold

I'd recommend moving to the Alumilite Clear Slow 12 minute open time to reduce the possibility of thermal cracks as well as running short on open time. Remember, the bigger the mass, the faster it cures. Therefore, if you mix more with the normal Alumilite Clear which has a 7 minute open time, it might be as short as 5 in a bigger mass.

Other very important thing is to stabilize your wood with Cactus Juice prior to pouring. This will, for all practical purposes, fill all the air voids in the wood with stabilized resin negating any possibility of issues with air pockets or moisture within the wood.

Mike