How do I cut doors in 26", 3/8" pipe?

[J.R.'s Butt Hutt]

Ok y'all you fabrication guys, Whats the best way to cut doors in a piece of 26" diameter pipe that is 3/8" thick and 70" long, and minimize warping or spring back? The pipe is going to be used for a firebox on a pit project. Tell me what you think.

[Clover Ridge Smokers]

I would use a plasma cutter.

[Big T]

I have used a plasma cutter and a torch and both worked fine. When I cut my doors out I usually leave some 1 inch tabs on all 4 corners and a few along my straight cuts. I let it cool off all the way and then cut my tabs, it doesn't always stop it from warping but it does minimize it. I have used a Metabo to cut the tabs but I'm not sure that it helped any.

[J.R.'s Butt Hutt]

Thanks guys