I built my UDS using 2- 3/4 intake ball valves and using a 8" pipe in the 2" top bung for the exhaust. Built a 15"x10"h fire grate sitting 2 & 1/2" from the bottom, the cooking grill is about 24" from bottom of fire grate. Read a bunch of threads and cannot get the temp to stay even at 225º. I put about 10lbs of K in the basket used a 3lb coffee can in the center and dumped in about 3/4 Weber of lit charcoal and put the lid on (removed the coffee can). I adjust the ball valves at 1/2 hour intervals and cannot get it right either running too hot or to low. I read where most of you set it and forget it for hours at a time. When I dump the lit charcoal in how long should I leave the lid off, am I closing it too soon before the fire gets going good? Should I try drilling 6-8 1/2" holes in lid and just block the bung holes, I am thiking maybe not enough airflow? What am I doing wrong?