Setting the Frame Width

The inside width of the frame is determined by the width of of sashes + clearance of 4mm. I marked this on cill and added the thickness off the pulley stile to give me the size of notches I needed to cut.

I cut these by hand. These extend the slope of cill, though the upstand to the width of the inside lining from the back of cill.

From this I could mark up the top frame rail, using the outer edge of the notch.

Cutting the slot to take the tongue of pulley stile using the cross fence, to the inside of the line.

Then (with hindsight) I should have cut the top rail ends to suit fit the outer rebate of the linings and slot the ends to fit the weight seperator. I realised later and ended up with this:-

I've also marked it up for drilling.