2X4 Chair

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Introduction: 2X4 Chair

About: DIY and Making-Wood, Glass and More!

Every night, I help my kids get ready for bed. My 7 year old daughter and 2 year old son share a room. There is one small pink chair that everyone uses: to read books, to brush hair, to get hard to reach items- we all sit in that chair. I have always thought we needed more places to sit in there- and my son needs his own chair! I have wanted to build one, and this was a perfect opportunity.

If you know me, you know that I am obsessed with chairs. I'm an embarrassing travel companion, because wherever I go- be it a store, restaurant, or hotel- I am walking around sitting in all the chairs, testing them for comfort. To make a long story longer, I wanted to make all the chairs- except the kitchen chairs that I hated: Windsor's. They are always coming unglued and snapping spindles. For years I avoided a book at the library called "How to make a Windsor Chair" by Mike Dunbar. I kept seeing some that actually looked nice, so I decided to give it a try. It was shocking for me to learn that Mike abandoned his career to build these chairs full time. I didn't quite understand how they worked, but I was interested enough to keep learning. In time I completely changed my mind when I understood that these chairs (when built correctly) are virtually bomb-proof, incredibly light weight, and supremely comfortable. I now follow ALL the Windsor chair makers.

Fast forward to quite recently and the same phenomena happened when I kept seeing "stick chairs." Some of these could be described as the "crude, ugly cousins" of Windsor chairs. Chris Schwarz just put out a book called "The Stick Chair Book." It completely blew me away and I had to build one (bucket list). I'm not sponsored, just an unapologetic SUPER FAN. Everything you need to know about chairs -in general and specific- is in that book. I used many principles I picked up there to design and make this chair. You could say this is the first chair I designed and built from the ground up- and I love it. If you want to build one like mine- the step by step and free plans are right here (print PDF on 11 X 17" paper). If you want to build ANY chair...I highly recommend his book.

Supplies

For supplies you will need 5 things: One rough cut cedar 2X4, wood glue, 2 brass screws (#10, 1-1/4"L), Bamboo BBQ skewers, and the finish of your choice (I had some Polyurethane on hand

For tools you will need all of them: Planer, Tablesaw, Bandsaw, Spindle Sander, Drill Press, Cordless drill, drill bits, "V" block with piece of hacksaw blade, "F" clamps, Bar Clamps, Hammer, Flush cut saw, Jack Plane or Block Plane, Chisel or Xacto knife with #18 blades, pliers (channel locks and side cutters), angle grinder + shaping disc, all the sandpaper you have.

Technically you could build this chair with dowels from the Home Center, a flush cut saw and a handheld drill...but I would recommend a few more if you want to finish it any time soon...like on a DEADLINE!

Step 1: Kids and Karate Chops (Anatomy of a 2X4)

Before we get into actually building this thing, we should say a word or two about construction 2X4's...how do I put this nicely?...they aren't...furniture...grade...

There is a reason people don't typically build furniture -much less chairs- with construction lumber. It might be related to the fact that you see little 8 year old's laying waste to boards with their bare hands. Some pretty impressive damage occurs when these little tykes start kicking and head butting that pine. Picture this: you build a slender, graceful piece of furniture, and your pint sized green-belt turns it to kindling- but I digress.

A 2 X 4 used to be exactly that, but over time they have become a standard 1.5" X 3.5" to account for surfacing and shipping. I went to the home center and picked a rough cut cedar 2X4 as it is not surfaced, and gives me a little more material to work with. You can see from the third photo that a regular 2X4 has a lot less growth rings.

Think of wood like a bunch of drinking straws stuck together with glue. A construction 2X4 might as well be large plastic straws glued together with kindergarten glue, while some hardwoods are like tiny metal coffee stirring straws bonded together with epoxy.

With those flaws in mind, make sure you get a 2X4 with arrow straight grain along the length of the board, and let's get to work.

Step 2: It Was BY DESIGN!

One of my favorite movie moments is from the Sherlock Holmes film where they are on the train and Sherlock yells: "That was no accident, it was by design!" I agree...

There is just not a lot of wood to work with in a 2X4, so a fair amount of planning went into maximizing every last bit of material. The seat and the backrest needed to be large enough for comfort, and that dictated what was left over for the the length of the legs and back posts.

I started by drawing variations of the seat on paper, choosing a semi triangular shape that would allow me to cut the sides of the seat shorter than the middle section. I'm from San Antonio and the back of the seat resembles the outline of The Alamo. I used a 4.5" radius to draw that outline. I drew full scale front and side views to work out any challenging areas.

The headrest was the next challenge. How can you get a comfortable curve from a tiny piece of wood that is straight? In Ergonomics, there is a shape called an anticlastic curve, which is like the shape of a Pringles potato chip: it curves from side to side, and up and down. I used a technique I picked up from watching Sam Maloof (rocking chair wizard) where you cut a curved piece from the front and glue it to the back. I did this twice, and achieved a headrest that curves both side to side and up and down. The side to side curve is a 20" radius that is very comfortable, and the vertical curve is a 15" radius. I played with the drawing to see if the headrest should be pointing up, like a smiley face or pointing down. Pointing down won because it seemed to be more comfortable and resulted in the strongest connection with the back posts.

I drew my components on to cardboard and cut them out. This gave me the opportunity to see any problems I might run into. The first was the back posts, I originally wanted them to extend down beyond the seat and connect with the back leg. Because I had less than 10 inches to work with, and lumbar (lower back) support is needed 7 to 9 inches above the seat, I had to change that feature. When looking at where the back leg and back posts needed to go, I realized that there would be 3 holes right next to each other on the edge of the 2X4- that would crack or explode with the tiniest bit of weight. It took me a couple days to figure out how I could ensure this area would be strong enough and still keep a tiny footprint. I leaned on what I learned from the plywood contest to come up with the solution: a section of cross grain slots at the back of the chair in the center that will reinforce the back leg and back posts without adding any visual weight to the chair.

The last thing to work out was the angles of the legs. We will look at this in the section on drilling the seat, but suffice to say that this will determine the comfort level of the chair, how it looks, and whether or not you fall out of it!

Step 3: Calculated Cutting

Alright, let's put steel to wood and start making this thing. The components to cut out to get started are:

  • One 13" Headrest
  • Two 13" center pieces for the seat
  • Two 11" side pieces for the seat
  • One 12 9/16" piece for the back leg (and scraps)
  • One 12 1/2" piece for the front legs,
  • One 9 3/16" for the back posts.

Because 7 cuts need to be made, and the kerf (amount of material cut away by the saw blade) is 1/8", almost one inch of material is gone making these first cuts. When you lay out your components, make sure to pick the straightest sections with no knots for the legs and back posts. The headrest and seat can have knots without too much trouble, but the legs and back posts need to be free from knots to 1) support the weight of a sitter and 2) be easier to taper with a hand plane.

Once the cross cuts have been made, rip the boards for the legs and back posts down the middle, so you have 2 pieces for each one.

Step 4: A Word About the SCRAPS

OK, let's talk about the scraps from this chair: there isn't any room for error here.

We need to maximize the thickness of the components so we have a strong chair, and when you rip the 3 boards down the middle for the front legs, back leg and back posts- you will be left over with a few slivers that are good as book marks or glue spreaders...they will be just thicker than a piece of paper. Since this chair has 3 legs and not 4, you will use the other half from the back leg to reinforce the chair in key locations.

Choose the side with the best grain for the back leg, and rip the other half into 5 pieces, 1/4" thick. These pieces will become the following:

  • 5 pieces that are 2" long. These will become tapered wedges for the leg and back post tenons.
  • 6 pieces that are just shy of 2.5" long. These will be the loose tenons that strengthen the seat
  • The remaining pieces will be used to reinforce the back of the seat and the front corners. You will need to cut the pieces as shown in the photo, the bottom piece cut at an angle will wedge into the front corners. The other 2 pieces have a piece that is 7 1/4", and what remains is cut in half. These pieces all fit into the slots cut at the back of the chair as reinforcement splines.

I cut all these pieces with a small handsaw, to make sure I had enough for each component. If I used a power saw with the 1/8" kerf, there would not be enough.

Step 5: Preparing the SEAT

The first thing to do is arrange the seat so it looks best. Once you have done that, draw a "cabinet makers triangle" on the boards to you know which board goes where. MANY times while building this chair I confused which board was what- left side, right side, front vs. back... this triangle is a sanity check to make sure you are cutting and orienting the boards correctly.

Reference the drawing, and measure and mark the location for the loose tenons. I placed the tenons where they would strengthen the chair the most, and aid in alignment when gluing it together. I placed the tenons toward the bottom of the seat, knowing that some of the top would be shaved away. I drilled holes to clear out most of the waste, then used my router to cut the slots. Test fit as you go to ensure the loose tenons will fit in each slot.

For the reinforcing splines, first glue together the 2 center (13") boards, then cut the reinforcing splines into the back, where the back leg and back posts will be. I cut 2 slots at the back, 1/4" thick, leaving about 3/8" between each slot. The slots are 2-5/8" deep. The slots in the front corners are also 2-5/8" deep, but are cut at a 45 degree angle as shown in the last photo.

Step 6: Gluing the SEAT

When gluing the seat, I like to compress the loose tenons with pliers. This compression will make it easier to insert the loose tenons, and once the glue hits them- they will swell and lock into place.

Glue the reinforcing splines into the back and front corners, then glue the whole seat together. I like to further strengthen the chair by pinning the loose tenons with BBQ skewers from the underside.

Step 7: Drilling Angles in the SEAT

This is where the magic happens, and the biggest "aha" moment I picked up from Chris Schwarz.

When I drew my chair, I created a front view and a side view of the chair. In his book, Chris explains how to understand the rake and splay (different angles of a chair leg) and drill it without any complicated math. There is even a tool he came up with and accompanying article on his blog of how this stuff works.

To come up with the angle we need (called a resultant angle) you need to mock up the legs of your chair. I created a seat template from 1/8" material. Drill a hole and countersink on the underside to accept a piece of wire cut from a hanger, epoxy this in place. Then, use pliers to bend the front and side angles into your chair. Now turn the model until the wire "leg" looks straight/vertical. The place this line intersects with the center of the chair is the resultant angle, and from there you set your bevel to determine what angle that is.

For this chair, the angles are 18 degrees for the back post, 12.5 degrees for the front legs, and 25.5 degrees for the back leg. I was a little conservative with the rake and splay of the front legs, and after having made it- next time I would increase that a little bit more. That's the beauty of these chairs, you can change any one of a dozen design elements and have a completely different chair.

I'm not super confident in my abilities to set a bevel and follow it by eye, so I came up with my own twist to ensure my angles are spot on. I take a block of wood and draw a line down the center of the board. This line will intersect with the resultant angle lines drawn on the seat. I mark this line on all 4 sides of the block. I then set my drill press table to the correct angle and drill through. Now, to drill the holes in the seat I simply line up the block with my resultant angle lines drawn on the seat, and use that block of wood as a guide bushing to drill the correct angle. I came up with this while building my stool from a past project. The last photo shows the different angle blocks with the legs in them.

Step 8: Shaping the SEAT

With the angles drilled in the seat, it's time for final shaping.

I bandsaw the outline and clean it up with a sander. Then, I bevel the underside of the seat. I set my table saw to 11 degrees and cut a bevel on the front and side faces. I don't cut this bevel on the back. The back curved portion is eased over with a 45 degree router bit.

The biggest problem to watch out for (maybe for woodworking in general, but definitely for this chair) is tear out. Remember the "wood-as-a-bundle-of-straws" analogy? Well, this wood leans toward the "plastic straw with weak glue" end of the spectrum. Because of this, I fill the holes we just drilled with dowels and cut them flush. This way, when I grind the shape into the seat, I won't lift and tear the fibers. You can see when I removed the dowels how a nice chunk split off from the bottom. This would happen all over the top when grinding if we didn't fill the holes somehow- or drill the holes after we shaped the seat, which would make it (nearly) impossible to get an accurate angle.

The shape of the seat is a 10" radius that intersects the back leg tenon through the center. It is 1/2" at it's deepest point. You can see the depth holes I drilled on the plans and in the first photo with the seat being sanded. When I get towards the front, I ease up and round it over.

Step 9: Making the LEGS and BACK POSTS

At this point the 3 legs and 2 back posts should be squares, and we need to make them octagons. I prefer to use the tablesaw. Set the fence to 45 degrees and rest the leg on the blade. Bring the fence over to the corner and that is the setting that will make everything octagon.

I decided to make the tenons 1-3/8" because that was the largest forstner bit I own and I didn't want to use a spade bit on the cedar. You could go up to an inch and a half with these tenons. The bigger they are, the stronger they will be. Chris Schwarz has a nifty chart in his book that shows how much strength you gain per 1/8" of wood you add to the legs and stretchers. There are many ways to do this, but I have a lathe so I chucked everything in the lathe and cut the tenons. I made a go/no-go gauge out of plexiglass to get the right fit. The tenons should be 1-3/8" round:

  • 2-1/4 inches long for the back posts
  • 2 inches long for the front legs, and
  • 2-1/2 inches long for the back leg

You can use the angle drilling guides to check the fit of the tenons. They should be nice and snug, but not too tight-as the cedar will swell when the glue goes on.

To taper the octagons, I created a planing stop on one of our benches with some "T" nuts and old baby gate hardware. I put the legs in a board with a "V" notch with a piece of hacksaw blade on the end that holds the legs in place. From there, take passes with a jack plane or block plane, working from the bottom to the top to get a nice, even taper.

Step 10: Making the HEAD-REST

The head rest has a little bit of magic to it. We are going to take a board that is relatively small and straight, and turn it into a piece that has a significant curve in 2 directions.

From the birds eye view, cut the 20 inch radius sweep and glue the front piece to the back. Once the glue is dry, clean it up on the sander. Then, mark the 15 inch radius sweep on the front face of the headrest and do the same as before: cut on the bandsaw, then glue the bottom piece to the top. I compared the sweep to one of my kitchen chairs that is pretty comfortable, and the sweep is actually a little bit bigger and more accommodating.

With the back posts temporarily installed in the seat, mark the location for the tenons. I drilled out most of the waste and cleaned out the rest with a Xacto knife with a chisel blade. If you don't have a chisel (or your 1/2" chisel is...dull...at the moment) then you can get away with the Xacto #18 blades, I won't tell anyone.

Because of the angle of the back posts, the mortise will be a little bit too wide once installed. I filled the gap with a piece of scrap that was cut off the back side of the seat (last photo). The gap is between 1/4" and 1/2" and as thick as the tenon.

Step 11: Final Glue-Up/Final Touches

This is a great time for a dry-fit. Make sure everything fits properly, and mark the location to add the wedges.

A WORD OF CAUTION: The wedges that are hammered in to lock the tenons in place exert a tremendous amount of force. If you orient the wedges with the grain, you are likely to SPLIT your seat in half. That would be a bad day. You want to cut the slots for your wedges and orient them so the wedges are at a 90 degree angle to the grain. I cut these notches in the tenons on the bandsaw, after marking where the tenons fit in the seat.

To cut the wedges, I started by trying to sand them. They are so small, and my fingers were so close to the sander, that I changed my mind after the first one. Instead, I cut a notch into a piece of scrap, and stuck the wedge on with double sided tape. Then I set my tablesaw miter to 4 degrees and made the cut. This created wedges with the perfect taper. Once that was done I added glue to the tenons, to one side of the wedge (yes, I am a glue on one side of the wedge kind of guy) and hammered them home.

After that, I cut the tenons flush, did a fair amount of sanding, added brass screws to the back side of the headrest tenons (for some shiny bling!), cut them flush, leveled the feet, and added leather "socks" to the bottom of the chair legs (these are glued on with hide glue and act as pads).

Step 12: The Result

In the late 1980's, my Wife's Grandpa made them a set of table and chairs for the grandkids (third photo). The table legs have no rake and splay, making it rather wobbly if you are not careful. The chairs are narrow and only accept very small hind-quarters. Nevertheless, we love them to death and still use them to this day. When the kids want me to play with them, I inevitably have to put a pillow over the arm rests and try to make it work. They want me to sit and color/cook/participate in what they are doing.

When I was in collage I worked in a wood shop, and one of the carpenters was re-creating a rocking chair that his grandmother had. It was surprisingly small, but even an adult could sit in it. I was surprised at this, and he told me to go around and measure things, that I would be surprised at what I found. It's amazing how a small thing could actually be comfortable, or how an Adirondack chair can be made so comfy even though it is comprised of straight boards.

Everything is made for adults- kids get the raw end of the deal. Everything is too big and uncomfortable, cutting blood flow off to their little legs dangling. To have a miniature piece of furniture that fits them perfectly, but can also be used by most people is a winner in my book. You should give this chair a try, it's super comfy- and you can make it with just one 2X4.

Is it stable? Yes, yes it is.

Is it sturdy? Yes, it is VERY robust.

Is it bomb-proof? Nearly. It can hold my (not insignificant) weight with a small child on my lap with ease- but I wouldn't test my luck and jump up and down on it.

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    6 Comments

    0
    MichaelWood
    MichaelWood

    5 days ago

    Gorgeous chair - definitely building a couple of those . . . . CHEERS !

    0
    MarkH342
    MarkH342

    9 months ago

    That is an absolutely great design! And the craftsmanship.

    0
    SimranWasu
    SimranWasu

    9 months ago

    Amazed with how the finished wood and grain looks! I really want to sit on it. Didn’t know there are multiple books on specific chair design too. Great guide!