Once you have trued your stock (to see how to do this, click here) put all four aprons in the vise with the face edge mark facing upwards. Use a chisel hammer and a square to ensure these are all lined up. Mark 1 ⅛ “ (29mm) from the end, use the square to square this across all 4 aprons. Do the same on the other side and go over both lines with a knife.
To lay out the tenons on the rails, register the square against the face edge and put the knife into the knife nick, square this across the face mark face.
Turn the wood over and flip the square so you are still registering it against the face edge face, transfer the line across the face.
For the final face, flip your square again so it is registering against the face mark face, transfer this line across using the knife nicks as a guide. Your lines should match up.
Tip: The first pass with the knife should be light then the second half should be heavier.
Set your 2 pins on the combination gauge to the width of your chisel (Paul uses a ⅜ “ (10mm) chisel). Center your gauge to the end grain of the apron (to see how to do this, click here). Once centered, mark the tenon along the end grain. Register the stock of the gauge to the face mark and follow these marks down the side of your tenon to the depth line. You can go over these with a pencil to make them more visible. Repeat the same on the other end and all the other 3 aprons.