First UDS Pork Tenderloin- UDS Temp Control

Hi All,

I recently bulit my first UDS and have been smoking the past five weekends. We have done ribs, chicken, butts, fatties and yesterday tried out a pork tenderloin.

I started the UDS w a baseball size amount of lump in a charcoal chimney and added about 2 lbs of Royal Oak Lump to the charcoal ring. The lit charcoal on top of unlit. All charcoal used is Royal Oak Lump. I had the ball valve and one of the caps off the pipe nipple. Capped the pipe and closed the valve halfway once the temps hit 190. The Temperature slowly climbed to 210 and held for about an hour. Then the temps slowly began to rise. I wasnt concerned until they hit 240. Once it hit 240 I shut down all airflow thru the valve. The temperature still kept right on climbing up to 265 with all vents shut down. It stayed at or around 265 for about a hour. I left all vents capped until the temps dropped back to 230. Then I reopened the ball valve to just over halfway. Temps kept dropping so I opened it all the way. It held at 210 for about a hour then began to drop again. This time I removed a cap and shut the ball valve down to half. This allowed me to finish the smoke at a temp of 225 which it held for the next two hours.

How do you all keep the UDS at a rock steady temp? I have read that most are able to leave one cap off and the ball valve cracked open but I would think the temps would be greater than 250 using that method. I start out with all caps on and adjust using the ball valve at about halfway open. Doing it this way allows me to keep the temps about 220 for the fisrt few hours of the cook. I would think that if I took off one cap and cracked the ball valve it woul allow too much oxygen creating a fire that is to hot.

The tenderloin turned out great.. good smoke ring tender and juicy.

Here are some pics.





Thanks for the Advice
HOPTOAD

My intakes are 1 inch holes with 3/4 inch pipe nipples w caps. The pictures I have show the drum with magnets over the holes. I have replaced the magnets with pipe nipples and caps. I think it might have something to the combustion rates of lump v brickett charcoal.

Here are the pictures of the drum.

I have four 1 inch intakes with 3/4 inch pipe nipples with caps on three of them. The fourth has the ball valve. The 3/4 inch nipples fit tight in the 1 inch holes. You are right about the combustion rates.. the lump definalty burns hotter, that might be it.

The drum pics I have are from before I adeed the pipe nipples and ball valve. I was adjusting the airflow with magnets prior to the caps/ball valve.



Thank you for the compliments on the tenderloin and the help w the UDS.
HOPTOAD