What're you doin' in here? Didn't you see the cobwebs and hear the crickets?
Aight, I might be a grouch but I can't ignore the fact that you took some trouble to post that.
Situation: 2 cables 8/3 w/gnd running to existing garage from 50A breakers (should be 40A breakers for that wire, I know), in 1" PVC conduit buried 30" or 36" (forget which). 1 cable feeds a 6 position 100A subpanel, 1 ends in an outlet for my welder. 5 of the 6 positions are occupied. I'm adding on a 12x40 section to the garage and have a 7.5 HP 30A full load compressor I'm cobbling together. Need at least one more lighting branch and two more outlet branches.
Opinions and suggestions wanted on options;
1. Replace the welder branch with 6/3 w/gnd and have compressor and welder share it, put a couple of tandem breakers in the existing subpanel for a couple more outlet branches?
2. Run another cable or 4 wires for compressor and welder and take the existing welder branch and feed another subpanel for more lights and outlets?
3. Pull it all out, run some fat wires (6? 4? 2?) to a 20 space panel and use 4 spaces for the welder and compressor?
4. something else?