Hold your cup of resin above the mold to help pop any bubbles as you're pouring, thats one thing I do. I also mix until I start feeling the heat from the heat given from the reaction, then I pour. You can also look into doxy 5. It'll help eliminate any bubbles if you cannot degas the mix. http://www.theengineerguy.com/Doxy-5-Urethane-Degassing-Agent.html