Ready for that sweet smell of pine sawdust? Well, it's pressure treated lumber so there will be none of that. Maybe you should wear a dust mask so that stuff doesn't get into your lungs.
1. CUT four of the eight foot 2X4s to 83 1/2" long. Use that miter saw or, if you're feeling muscular, a hand saw!
2. DRILL HOLES! Line up these boards side by side (flat side down) and mark out where you are going to drill. You want to drill right in the middle of the board. If you want a full set of rungs of both sides do all four boards like this. Otherwise do two boards like this and the other do as shown below.
Mark where you are going to drill, measuring off every twelve inches starting at the bottom. Your square could come in handy here. If one side is going to be a hangin' side mark the first rung nine inches from the top and the next twelve inches below that.
Start drilling! Try to drill straight up and down if you can. I'll wait right here.
3. CUT 8 or 12 two foot lengths of dowels (again, cut 12 if you want rungs on both sides). It's okay if it's a quarter inch or so shorter than two feet.
4. ASSEMBLE ! Lay one hole-riddled board flat and insert six dowels. Use that rubber mallet and smack 'em all the way through so they are flush on the back side. Now place another board on top and pound it down so the dowels are all the way through and flush with the top of the board. I recommend you do this on concrete or other hard-ish surface. Do your best to keep everything square but it should all be pretty close anyway. Neat little ladder, isn't it?
5. CUT four of the eight foot 2X4s to 87" long.
6. SANDWICH! Take two of the 87" boards and sandwich the ladder you just made. Screw them together using the exterior screws every twelve inches or so. If you want it to look nice screw from the inside between every rung. Use your clamps if you got 'em to hold the 2X4s snug against each other while you screw for a nice tight fit. Be sure that the bottoms of the boards all line up nice and straight.
7. REPEAT. Do the same thing to the other side/ladder that you built.
8. CUT two 5' 10" lengths from the eight foot 2X4s. Don't throw away those scraps, though. You'll be needing them soon enough!
9. SET your miter to 45 degrees and chop of the corners of these 5' 10" pieces. These will be the bases of your set and you don't want pointy corners. You can do a simple 45 degree chop or you can get fancy and make the taper longer. It's up to you.
10. SCREW the base onto the bottom of each ladder sandwich. Center it as best you can and use three or four screws on each ladder leg.
Hey, an entire post with no political commentary! YEAH!
UPDATE: For one of the sides I would recommend three rungs on the bottom only, leaving the top three out. This way kids can climb the three steps and hold onto the monkey bars to swing out. Slight design flaw...
Next up - The Top!