Impressive, both in workmanship and design! 
First viewed this on my mobile and thought you had used solvent weld for the joints, but now I see you (also) screwed them. 
Must have taken a high degree of skill, especially with only one hand to do the work. 
Photo makes it look like the central columns make getting the feet on the pedals a bit awkward though? 
Is that just the angle of the shot?