The following took 4 hours including a trip to Lowes to get the wood.
I start out by cutting out my lower back brace and legs. The lower back brace will need to have the curved side cut at a 7 degree angle on the band saw.
Then cut my 1×2’s into lengths of 23 inches. You need about 10 because the seat is roomy.
Then make a frame. Be sure to get the frame as square as you can. I usually consider it square when the seat slat and the lower back brace measure the same distance on each side. You’ll have to keep checking that distance as you attach every other seat slat.
Using spacers I made, I finish attaching the seat slats using four tools for each screw hole. A punch to start the pilot bit without scarring the wood, a 1/16th pilot drill, a bugle drill, and a screw gun.
It may seem like a lot of work, but neat screws are a must on my work. I hate sloppy screws, lol.
Keep measuring to make sure you have it straight all the way.
If you get off a bit on one side, just use a wedge to add a little back. You can’t see it with your naked eye.
Two twenty inch 2×4 fastened with 6 two inch screw, 3 inside, 3 outside. Some people use bolts here, but bolts are ugly and loosen up.
Completed chair seat ready for arms and back, Part II.
I always add a brace under my lower back support. It makes the chair very solid. I believe I’m the only one doing this.
-- A positive attitude will take you much further than positive thinking ever will.