Marking out the mortices

Time for the second measurement. Mark one of the bottom sash stiles to the right finished length.

Mark up the mortice from this length using the tenon of the bottom rail.

Offer up the two stiles and transfer the top mark across to the second stile.

Mark the bottom of the mortice on the second stile using the other tenon of the bottom rail

5/8 bit in the morticing machine and cut to the marks making sure the upstand of the rebate is flat against bit.

Assemble the bottom sash as far as the bevel will allow. Offer up the top sash with the rebates of the top rail of the top sash against the bottom rail of the bottom sash. Then mark up the mortices for the top sash meeting rail.

Cut these mortices and assemble. Mark across using the flat chisel against the bevel of the rails, to see where the bevel on the styles needs cutting back too.