A good bunk bed needs a good ladder.
I’ve never made a proper ladder, but I’ve read up on wooden ladder construction. Many traditional wooden ladders had threaded rod under top and bottom rungs to make sure everything didn’t come apart in use. Others had the top and bottom rungs in wedged through-mortises for the same reason. For mine, I decided to use dadoes to hold the rungs (sections of 2X4) but to double up on the joinery for the top and bottom rungs. They are set in dadoes, but they also feature wedged through-tenons so that the uprights can’t be pushed apart.
Laying out the mortises was interesting. I couldn’t use a mortise gauge because the tenon shoulders were not parallel to any of the workpiece’s regular edges. I drew pencil lines with a sliding T-bevel instead. The order of operations was crucial.
First, I left the top and bottom rungs long. I cut all the other regular dadoes and dry-fit those rungs. Then I laid the top and bottom rungs over their dadoes so I could get an absolutely precise measurement for the shoulders. Then I cut the tenons and stood them on end in their respective dadoes so I could gauge their location. I used a marking gauge (reset every time) to mark out the mortise locations. I bored out most of the waste with a brace and bit and used a chisel to square up the mortises. Except that the mortises aren’t square. They’re rhombuses. Can one rhombus up a mortise?
Secured with an oak wedge, this joint is never coming apart.
The glue-up took every long clamp I had.
I intentionally chose slightly bowed stock for the uprights. I oriented the uprights so they bowed inward just a bit. The clamping force then pulled the bows back to straight, theoretically keeping the middle nice and tight. I still had to close up the middle joints with clamps.
After a few coats of lacquer, it was time for installation. I glued leather on the feet and felt on the top where the ladder contacts the wall. Then I screwed it to the end of the bed frame. The top and middle bunks are now accessible from the same ladder.
I have two happy daughters, and one who’s pouting at the moment. It’s bed time, after all.