I have been using satin cast 20 for a long time and last 100lbs tub is not mixing like all tubs in the past. I measure to the gram and have used 100/38 ratio of investment to water. After mixing now investment to to thick to pour. I have gone to 100/40 ratio and it’s better but still thicker than 100/38 of the past. I have sent request for info to Kerr with only auto reply to this point. I have also confirmed that my digital scale is accurate as are my digital timers. Any suggestions?