I thought that too when looking at that picture which prompted me pulling a tape from the frame to the wheel and double checking. The picture is at a bad angle as there is less than 1/16" difference between them.
I did take the time to put a framing square (and a speed square) on it, even after saying I wouldn't today, and it shows that my top platen wheel is cocked up a little on the right side. The bottom is also a little out but I think the problem lies more with the top one. I'm going to have to redrill and tap the holes for those two wheels or figure out a way to weld much more squarely next time. I think I'm going to rebuild even after finding what looks to be the main problem. I found other issues I don't like including too much sloppy welding (I was using a flux core wire welded on this and results look hideous) and adjustments that just aren't right.
Before I build the next one can someone tell me just how much tension should be on the slack of the belt? I feel like I shouldn't have as much play in there as I do. This is one finger pushing on my off hand (can't take a picture with my off hand cause I'm not that gifted).