What voltage/amperage garage circuits should I install for welding tools and an air compressor?
I'm sure this question is moot for the original writer but for anyone else with a similar interest, the important point is that the garage is going to be used as a shop and the electrical infrastructure should be flexible to accomodate future needs. Thus I would recommend you install a 100 AMP sub-panel (220V of course) and surface mount it so that you can run new romex to new surface mount receptacles as needed. Go ahead and install the receptacles you know you need now. When/if you want to rearrange your shop or get new heavy machinery, it will be easier to wire them up.