This is an outdoor lounger I built out of an old pallet. It was a little bit of trial and error to get a good seat height and angle to be comfortable, but in the end, I must say, it is rather comfortable. (for a chair with no cushions) Most of the joinery is half lap joints which i accomplished with a skill saw (my tool of choice) and a sharp chisel. I find these joints to be strong, attractive and effective if done right. I'm sure you all do, but for those who don't know what a half lap joint is, it is where half the thickness of the material is removed from each of the pieces to be joined resulting in a puzzle type fit. If this joint is cut tightly enough, it is very strong and flushes out nicely resulting in sleek profiles.
Step 1: The "X"s
I started by dismantling two oak pallets, and laying the rails out on
the ground to find a good orientation for the X shaped "bones" on the sides. The angle i found as measured on a speed square was approx 25 - 26 degrees. That is the angle of the half lap cut, not the angle of the seat. I Joined the "X" at the desired angle and orientation. I then held the "X" upright and laying a level on the ground, up against the legs i marked the cuts at the bottom of the legs so that they would sit flat on the ground. I carefully sat in the "X" to make sure the angle and height would be comfortable (took some adjusting). Once i felt that the overall "X" was good, i copied it for the other side only reversing the side of the rail the joint was cut into.
Step 2: The Stretcher
I then had to cut a stretcher to connect the two sides at the correct distance from each other. I did not want to see a bunch of screws holding this together plus screws kinda loosen up as time and stress wear on an item. Instead I tried a joint that i saw but am not sure what it is called. Basically I cut some square tenons on either end of the stretcher and sanded them round on the belt sander. The ending diameter was 3/4". I then drilled 3/4" holes in the center of the "X" members to accept the round tenons. I then cut a slit down the length of the tenon before placing it in the hole. This slit is to accept a wedge shaped piece which is pounded into the slit to expand the tenon thus securing it in place through pressure. Do not wedge it yet. It needs to come apart.
Step 3: The Rabbet
This step requires you cut a rabbet out of the tops of the the pieces that make the "X" for the seat slats to sit in. With a straight edge, I marked a line 3/8" in from the edge from the half lap cut to top of the back on one piece and from the half lap cut to the end of the seat on the other. Be careful to keep track of which side faces the inside as that is the side to be cut. I then marked a line on the inside face of the pieces using the slats to determine the depth of the rabbet. Cutting these lines will remove the corner leaving the rabbet at the edge of the piece. By the way i used a skill saw with an old blade as i knew i would be cutting through a crap ton of nails. Also you have to raise and lower your blade according to how deep you want to cut, and i suggest safety glasses. Do this on both "X"s.
Step 4: Some Assembly
At this point you can assemble the "X"s with the stretcher using the wedges in the round tenons to hold the assembly together. Measure the width of the chair from outside to outside at the location of the stretcher. All other pieces from this point will be cut to maintain this measurement throughout the rest of the chair to keep it square. There is another stretcher at the back legs that sits in a notch so that it flushes out with the top of the leg. This is sometimes called "letting in". I also let in some diagonal bracing on the back side of the chair back. This is to keep the chair from racking and to keep the width of the chair consistent.
Step 5: The Slats
Now you can cut your slats for the seat and the back. These all must be the same length to keep it square. Predrill and screw. Once these are cut and installed, we come to the front of the seat. I cut mine at and angle to keep from having a sharp edge at the back of your knees. I ripped the front edge of the front slat at a corresponding angle and added a piece across the face with a cut mimicking the cutouts in the rails for the forklift forks.
Step 6: The End
To finish, i just sanded the chair enough to make it comfortable. I left the rustic character of the wood visible as that is the charm of working with pallets, other than the whole free thing. I did not put any kind of coating as i want it to continue to age in the sun. So there you have it. A pretty sweet chair.