Things to note: The front and back legs are not meant to be parallel. Refer to the
plan for correct placement.
You may need to place a temporary spacer (block of wood) between the bottom of the front and back leg to hold the side frame firmly in the correct position while it's being
Make the spacer 25mm shorter than the side seat rail to achieve the correct side profile.
Step 4: Make a notch
Cut a notch in the wood on the inside edge of both back legs 32mm down from the top, in order to house the back top. See fig.4 and fig.4a.
This is best done by making multiple saw cuts 20mm deep across the notch area and then by cleaning the area out with a sharp chisel.
Step 5: Assemble the frame
Time to assemble the rest of the frame (fig.5).
Cut the back top unit to length so that it fits neatly into the notches in the back legs.
(Remember in step 2, the two horizontal back pieces were cut over length until such time as they could be measured exactly.)
Clamp the two side frames to the seat front and rear rails, ensuring that the two back legs are parallel.