Need some help with casting issues. I'm using the Core 550 and the emerald resin. I follow the burnout cycle recommended by B9. I'm casting single pieces in 2x 21/2'' flaskes using Ransom & Randolph investment, a Naycraft Spincaster and propane/oxygen. Small production, I only cast about 3 to 5 pieces a week.
I have attached images of the surface issues I've had on every piece I have tried to cast. Would really appreciate any help on this.