The design for this chair had one unique feature
4 chairs had to be made with only one twelve hour period access to the workshop. 
The workshop had a good table saw, a band saw, a dowelling drill (homemade) and a hand held belt sander.
To achieve that goal there are no complex angled joints.
Some assembling and the upholstery work was done later.
The construction is sound and the chairs will not become rickety  with age.