So now that we have the dados cut in the frame pieces, it’s time to cut the miters.
I start by scribing the angle with the marking knife and carry it around the entire piece using the combo square.
Then I clamp the piece down to the bench top and saw it off close to the line.
Now I have to clean up the saw cut on the shooting board.
I position a speed square against the fence to get the 45 degree angle and clamp it in place.
I find this technique to be very reliable and very repeatable.
Once I have all the angles cut and shot I make sure that the two long pieces and the two short pieces are the exact same lengths, this will guarantee a square glue-up.
Now I need to size the panel to fit the frame.
I measure the bottom of the groove and mark the panel 1/8” smaller to allow for seasonal expansion (1/16” either side). I make sure keep the seam of the panel centered by removing material from both sides. When I make the rip cuts I stay away from the line by about 1/16”
The sawn edges need to be brought down to the line with the plane.
This technique comes from Christopher Schwarz.
Elevate the panel on a scrap board and hold it against a stop and let the edge hang over the scrap board. Trim the edge with the plane laying flat on the bench top. It works extremely well and keeps the edge of a thin panel 90 degrees.
The narrow edge of the panel can simply be trimmed to size on the shooting board.
If your blade is sharp you will get nice solid end grain shavings, not dust.
This panel is around 3/8” thick and the groove is only 5/16”. I turn the panel to the back side and use a block plane to chamfer the edges intil it fits all the way into the bottom of the groove.
Tomorrow I will mark-out and cut the holes for the weather instruments.