Interesting seeing the originals! The B&W conversions are good, although I find the first too contrasty for my taste.
I think you should include the hands in the first one - it makes it clear that he's doing something. Too bad about the background - I can see why you were trying to de-emphasize it. Something to keep in mind for next time, I guess. But that's the trouble with photographing people doing stuff - they insist on doing it in cluttered workshops and the like! I have some pictures of my father tinkering with stuff where I really like the pose, and what he's doing, but it was simply impossible to avoid getting racks of tools and power equipment in the background.
In the second I can see why you cropped out the light on the ceiling, it's distracting, but I agree with the others that a wider crop would be preferable. How about mid-chest to the top of the wall in the background, and take off enough on the left to lose the object at head height? I like his stolid pose, I don't think it matters much that it's not much of a "moment", to me it says, "I'm enjoying a cigar in the sunlight, don't bother me with stupid health advisories!"
Nice portraits, I wish I could get people with their eyes open and their mouths closed...
Julie