7th graders have been using these plans for five years to build Adirondack chairs. These plans are reliable and after as little as three hours of work, you can have an unstained/painted chair! The plans that we are following today can be found through Shaw Creek General Store.
Step 1: Collect Your Supplies
This supply list can be modified, depending upon what you already have access to. The list includes:
1 box 2" deck screws
1 box 1 1/4 deck screws
10" Mitre Saw
Palm Sander with #220 and #100 paper
Corded and cordless drills with variety of drill bits
Level, 'L' and tape measure
Step 2: The Wood
You need to purchase three sizes of lumber (preferably pine with very little knots):
Try to purchase lumber that is free of too many knots and is semi-sanded. This lumber is available at any local lumber yard, and should run you about $45-50 total.
Step 3: Designing Your Chair
Your chair can be unique in many ways, the easiest being the back. But the leg height and angle of the arms can be specifically set to whatever level you would like. Take a few minutes before you begin working to develop a plan for personalization. Doing so will save you time and headaches later on!
Step 4: Measuring Lumber
Measuring your lumber: DOUBLE check all measurements!
Cut your lumber into the following measurements:
The 1x4 lumber needs to be cut into the following measurements:
5 44" back slats
5 23" seat slats
2 24" legs
2 10" arm supports
1 26 3/4" middle back brace
1 20 3/4 top back brace
The 1x6 needs to be cut into 2 32" arms
The 1x8 needs to have 3 35" stringers, 1 23" front brace and 1 20 3/4" bottom back brace come out of it.
Step 5: Cutting Lumber on Mitre Saw
Use dominant hand to hold lumber steady, and a friend to help keep longer pieces from moving. Don't forget to use safety glasses when cutting! This can be a powerful and dangerous tool, so if possible, have another set of hands available to hold lumber down while you are cutting it. This will help to avoid rough cuts or accidents.
It's also suggested that a mitre saw with a laser measurement be used.
Step 6: Assembling Your Chair Back
Assemble the back slats (44" 1x4 pieces) first. Then, use the jigsaw to cut the back in the pattern your designed earlier. Use scrap wood as spacers to even out your back of the chair. Use the 1 1/4 screws. Connect the middle back brace (26 1/4" 1x4) to the slats first, followed by the bottom back brace (20 3/4" 1x8). You should then connect the top back brace (20 3/4" 1x4) towards the top end of your back.
Very important: Remember that before actually screwing lumber, you pre-drill with your bits. Otherwise, you can easily crack the wood, thus costing more money to replace your lumber!
Step 7: Assembling Your Chair Base
Connect your two legs (24" 1x4 each) to the stringers (35" 1x8, each). Before (or after) you do this, you should round one end of the stringers using a large cylinder (like an old coffee can) to make a rounded edge. On the other end, cut an angle so the front brace (23" 1x8) and stringers are even and straight. Once you've attached the stringers to the front brace, evenly measure how high you want the front brace to be on your chair. Usually, 6-8" from bottom of the legs to the bottom of the brace is where most chairs are set up. Make sure to use your level to get the angle correct!
If your legs wobble because one is slightly longer, you can jigsaw them down to get an even feel to them!
Step 8: Putting Two Sections Together
With a partner, connect your back section to the base at the stringers. You will want to decide on the angle of the back and how far back you want to sit in your chair. The best way to do this is to measure a spot from the rounded edge of the stringer, mark it with a pencil, and replicate this process on the other end. Then, it is strongly recommended that you use 2" screws to connect to the back through the stringers. To reinforce the back, take leftover scraps, cut them to the same size and placed them on the inside of the section to reinforce the chair. Then run additional screws into this section from the stringers in, preferably 2".
Afterwards, assemble your sleet slats (five 1x4" cut pieces to 23") and attach them to the stringers using 1 1/4" screws, two per side of each slat. Be careful that you leave a gap between your last seat slat and the back, so water can flow to the ground. The slats should taper, so you may need to cut overhanging lumber with a jigsaw afterwards.
Step 9: Adding Arms and Supports
The arm supports can be cut in any design you prefer. Use two pieces of 1x4 cut to them to 10", then jigsaw these edges for a neat pattern. Next, screw the supports from the inside of the chair, so the screws go through the leg and into each support. It's suggested to use at least two 1 1/4" screws for this task. It is suggested to draw lines where you plan on attaching these supports before you actually do this. That way the supports are straight!
Your arms should be cut at 32" from the 1x6x6. Then, create a design for the front end of the arm. Once this has been done, cut the front of the arms to shape using the jigsaw. The arms are attached on the middle back brace overhang. You may want to use a belt sander (optional) or your jigsaw, to trip a flat groove for the arm to rest upon. Attach the arms to this piece and the leg and arm support. It is suggested that at least 1 2" screw is used to connect the arm in the front. To guarantee the arms are level, use one!
Step 10: Sanding and Finishing
Use a palm sander, when possible, to sand down the rough edges. Pine should be pretty smooth, so this won't be a difficult process. Don't bother sanding all surfaces, as you will only be touching one side. I suggest sanding once everything has been constructed, but you can sand seat slats and back slats before assembly if you know which sides are facing out/up.
Don't over sand, and ALWAYS sand with the grain.