Repeat Step 2 to make a second assembly exactly the same (you turn it 180° when fitting together). Glue and nail spacers against inner slats on this tabletop half only. This completes the 2 tabletop halves
Test fit halves together. Centre cleats slide against each other and there should be a 90mm gap adjacent to cleats 400mm in from each end.
Find centre of 1 rail, then glue and screw 1 of the legs to rail using four 35mm screws. Use square to ensure leg will be straight. Repeat to make a second T-leg assembly.
Make 1 square leg assembly by screwing 2 rails to 2 legs, so they are flush at top and ends, and bottom rails 100mm up from bottom. Check diagonals to make sure assembly is square. Repeat to make a second square assembly. Sand tabletop and leg assemblies.
Paint tabletop with 1 or 2 coats of Cabot’s Stain & Varnish depending on how dark you want stain. Paint legs with 1 coat of primer, then 1 top coat (we used a contrasting semi-gloss off-white) allowing paint to dry between coats.
Screw hinges to top inside of T-leg assemblies so they are flush at top and with ends. Screw T-leg assemblies to square leg assemblies.
Close up legs of 1 trestle and drill a 10mm hole through centre of where T-leg crosses bottom rail of square leg assembly. Cut rope about 500mm long and tape ends. Feed rope through holes and spread legs so they are about 400mm apart at bottom. Thread rope through hole and tie figure- of-eight knots at each end as a stay. Repeat for second trestle.
Set out trestles so T-legs are at ends and place tabletop on top, so top rails of leg assemblies sit in 90mm gaps on underside of tabletop.
Here's the handy diagram: