Thanks everyone for their input. I'm heating up corn, letting sit for 2 hours, adding rye, barley and barley malt, letting sit a couple of hours, cooling down with a cooling coil and adding yeast, then draining out to finish fermenting. Not possible for me to use steam jacketed equipment. I started operation at 65 years of age, am 68 now, would never get a return on the money it would cost to do that.
Special situation. I have drilled some larger holes in my screen randomly and if that improves the draining, will put in more.
I double screen/filter before it goes into the still. I get some decent returns so will just keep plugging (no pun intended) along.