I built a king size bed and two bed side tables gratis for our young friends. The wood was 1” quarter sawn white oak. The bed was normal king size, but had a large solid 8’ by 5’ headboard also of white oak.
The major elements of the bed frame were four 1” by 6” by 10’ glued together. I put the boards through a planer, glued them and then clamped them together on a door I bought from Home Depot. Doors are dead flat, even the cheap ones and provide a perfect glueing platform. The four 2” by 6” by 10’ beams came off the door perfectly flat.
I did use the 700 connectors paired with standard dowels. The bed was built in my shop and assembled in their house. It’s been there several years and is still rock steady even with two kids using it as a trampoline as well as the young couple.