To create a straight edge at end of door, use large square to draw a line across it where timber is sound. Use fine handsaw to cut timber along this line. Repeat for other end of door.
To create table legs, draw a square line across door 350mm from 1 end. Use handsaw to cut along line. Repeat for other end of door. Wet-sweep sawdust and collect to safely dispose.
Cut joining batten to length 20mm shor ter than width of door, here 880mm. Paint 2 adjacent faces and both ends with black acrylic paint. Let dry. Spread PVA on narrowest unpainted face and place batten on leg flush with end, with a 10mm gap to edge of leg at each side. Make sure a painted face is facing back towards leg. Predrill, countersink and screw batten to leg, ensuring screws don’t come through other side of leg. Repeat for other end of table.
Glue and screw table-leg assembly to underside of tabletop so outside face of leg is flush with end of top. Repeat for second table-leg assembly.
Cut brace with a 45° angle on each end, going in opposite directions across timber. Paint with black acrylic paint and let dry. Place on inside of table between leg and top. Use square to make leg 90° to top. Screw brace into leg and top. Repeat for other end of table.
Apply 3 coats of clear polyurethane to table, allowing to dry after each coat. Ensure all surfaces are covered, including underside.