Cómo montar una silla de madera Adirondack

How to assemble the Adirondack chair

Once we finish making all the wooden pieces, it is time to assemble the Adirondack chair. And despite we can fin some instructions in the chair plans, I will show it in more detail. And I also include some improvements and some tricks you won’t find in the plans. The thing is that the first time we assemble one Adirondack chair, it can be a headache. So let’s see every step of the assembly. Or you can watch the video so you don’t loose a detail.


How to assemble the Adirondack chair frame

How to assemble the Adirondack chair sides

First I will assemble the side supports. So, I’ve clamped a straight strip on the workbench. And just to lift it a bit, that strip is on a couple of plywood templates.

Then, I measure 11.5cm from the front of the side supports and I make a mark. And I put the first side support against the strip. Right the way you can see in the picture.

Measure 11.5cm from the end of the side support

Now I put one front leg under the side support. The edge of the front leg must be exactly in the 11.5cm mark. And the front leg must also be at 90 degrees with the clamped strip.

Screw the side support to the front leg

And I drill four guide holes and I insert four screws.

Notice that I begin to drill in the side support, not in the leg. Like this, once I finish the Adirondack chair assembly, the screws head will be hidden in the inside part.

Make a symmetrical side for the wooden chair

Now I can assemble the other side support with the other front leg. But notice that now the side support looks to the other side. Like this both sides of the Adirondack chair will be symmetrical. Because they must be symmetrical, not identical.

Assemble the lower back support of the Adirondack chair

Next I will assemble the lower back support. I fit each end in the notch in each side support, and I insert one screw in each end. I make sure I have a 90 degrees angle between the lower back support and both side supports, and I insert another screw in each end of the lower back support.

Before inserting the screws, I always drill guide holes.

Stainless steel wood screws

To make all these wooden joints I will use stainless steel screws. Specifically, I use 6cm long stainless steel crews and 5cm long stainless steel screws. All them are 3mm thick. The 6cm ones are perfect to assemble the 3cm thick parts of the frame. The 5cm long ones are to assemble the back and the seat slats. But I think these 5cm ones are too long. Maybe 4cm long screws would be enough.

How to set the distance between the back legs

Now I must set the distance between the back legs. So, first I clamp a strip on the workbench. Now I put the front legs against that strip. And I put the back legs the way you can see in the picture. Notice that the bottom part of the back legs are also against the strip. And then I clamp them in the inside of the side supports.

You must also check that, the inclined cuts, in the top part of the back legs, are both looking up.

So, now I centre the upper back support on the back legs and I screw it.

Centre the upper back support of the Adirondack chairScrew the upper back support of this wooden chair

And now I realise the are two small wooden corners protruding the inside part of the upper back support curvature. So I mark the shape of those corners and I will cut them once I unscrew the upper back support. Actually I can unscrew it now, I can cut the corners and I can screw it back again. Or I can put first the back legs in their right position. This about cutting those corners is something you won’t find in the instructions in the plans.

Mark the wooden corners that protrude the upper back supportCut the wooden corners that protrude the upper back support
How to set the back legs position

So now I will set the back legs position. They must be perfectly vertical, so I use a square to check the angle. But the trick to put them in the right position is to use a back slat to align the curved edge of both, the upper and the lower back supports.

Screw the back legs to the Adirondack chair side supports

Wen I think they are OK, I measure to make sure both back legs are at the same distance from the lower back support, I clamp them, I make sure both are vertical. and I insert four screws in each leg.

Centre and screw the armrests supports

So I have already assemble the front and the back legs. And between them I will put the characteristic wide armrests that help to stand out Adirondack chairs. But first I centre the armrest supports in the outside part of the front legs. I clamp them and I screw them.

The support block to screw the armrests on the front legs

Next I will mount the armrests. In the plans we can find a rectangular piece that is called support block. I should use it to make a rectangular piece out of solid wood, and then I should screw it on the front leg and on the arm support. Then I would put the armrest on it so I can insert some screws from the block support to the armrest.

We must keep in mind that the size of those support blocks depends on the thick of the wood we use to make the frame pieces. Besides, if we use those support blocks, we must put one of them on the front leg template when we level the armrests (we’ll see that later). I mean I should put the solid wood support block, not the plywood template.

But instead of using the support blocks, I will use a different technique to screw the armrests. Something you won’t find in the Adirondack chair plans.

How to drill pocket holes to screw the armrests

Then, instead of those support blocks I will use pocket holes. So I will drill some holes at an angle.

First I will use a drill bit with the same diameter as the screws head. But I will drill just half the way. And then I drill the guide holes (with the usual drill bit I always use to drill the guide holes) inside the bigger holes.

First I drill the wider holesNow I drill the guide holes inside the wider holes
Check that the screws won't protrude the armrests surface

Once I have finished drilling the guide holes, and just to make sure the screws won’t protrude more that the armrest thick, I insert one screw in each hole. I use that piece in the picture, because it isn’t as heavy as the armrests.

But before screwing the armrests to the front legs, I have to screw them to the back legs.

So now the front legs plywood template will help me to level the armrest. I align the back of the armrests with the edge of the back legs, and I insert the screws from the back legs to the armrests. Now it begins to look like typical Adirondack chairs.

How to level the armrests of this garden chairSet the position and screw the armrests to the back legs
Screw the armrests of the Adirondack chair

To continue with this Adirondack chair assembly, now I can screw the front of both armrests. I align the inside edge with the back legs and I insert the screws.

According to the plans, now the Adirondack chair frame is ready. But as we could see in the previous post, when I made all the parts of this wooden chair, I also made two smaller armrest supports that go in the back legs.

How to rip the back armrests supports at 45 degrees

Then, first I will rip them with a 45 degrees cut. Something easy if I use my 45 degrees cut sled. I just must make sure that the pieces I make will be symmetrical. That is why when I cut the first one, the top part looks to the back of the sled. And when I cut the other one, the top part looks to the front of the sled (you can watch that in the video).

And now I screw them in the back legs and under the armrests. I insert the screws at an angle. And before I insert the screws, I must make sure they won’t protrude the other side.

Insert the back armrest supports screws at an angleBack Adirondack chair armrests supports

Adirondack chair assembly: back slats and seat slats

Screw the first back slat in the Adirondack chair assembly

Once I have assembled the Adirondack chair frame, I can assemble the back slats and the seat slats. First I will screw the outside back slats. So, I want to align the outside edge of those slats with the end of the upper and lower back supports curvature. And I want the bottom end of the slats to be a couple of centimetres under the lower back support. So, when the first slat is in place I insert one screw against the upper back support.

Screw the slat in the other side of the back

Now I will put the slat in the other side of the back. This one must be symmetrical to the first one. So, I align the edge with the end of both curvatures, I measure to make sure it will be to the same height as the first slat, and I insert one screw against the upper back support.

Screw the bottom part of both slats

Well, I also insert one screw against the lower back support.

And now one of the most difficult parts when assembling one Adirondack chair: get perfectly aligned back slats. But it is very easy to get them aligned if we follow a couple of tricks:

The first trick is to nail one slat under the two back slats we have already assembled. So now, if I rest the other back slats on that slat I have nailed, then all the back slats will be perfectly aligned and to the right height. The first time I assembled one Adirondack chair it was a mess until I could align them. Now it is very easy if I follow this simple trick.

Nail one slat under the back slatsPut all the back slats in the Adirondack chair
A spacer helps to screw the back slats

And now the second trick: if I make a simple spacer, like the one you can see in the picture, it is very easy to keep always the same distance between all the slats. So, I put the spacer against the slat in one side of the back, I put the next back slat against the spacer, and I screw the slat against the upper back support. And I keep doing so until I have screwed all the back slats.

I eyeball to screw the bottom part of the back slats

Now I eyeball to position the back slats against the lower back support, and I screw them.

I get rid of the slat I had nailed to the back slats

And I get rid of the slat I had nailed to the bottom of the back slats. Once I have aligned and I have screwed the back slats, I don’t need it anymore.

Finally I can assemble the seat slats in the frame of this wooden chair. Essential if we want to seat on this garden chair :).

Cut two notches in the first seat slat

Here we will see another thing you won’t find in the plans: The first seat slat bumps against the back slats, so there will be a big gap between that seat slat and the lower back support. That is why I decided to use the jigsaw to cut two notches. As you can see in the picture, I made tilted cuts so the slats fit nice around the back slats.

Screw the frontal seat slat

Then, I put all the seat slats in the wooden chair. But I don’t screw them. I just make sure there is enough room for all the slats. Now I set the position of the frontal seat slat, that with a decoration, and I insert a couple of screws to each end of the slat.

And now I can screw the first seat slat. The one with the notches. I screw it at a couple of millimetres from the back slats. So I have assembled the first and the last seat slat. And I have all the other slats in between of them. I just need some spacers to have the same distance between them.

Put some spacers between the seat slats

The thing is that the best spacers I could find are the screws I use in this Adirondack chair assembly. Except in the front curvature. There I use some washers.

And as we can see in the picture, in that curvature the slats don’t rest well on the edge of the side supports. But in my last post we could see how to route there three flat surfaces so the slats rest well. You won’t find that in the plans. But you can find here how I made it.

Screw the seat slats of this wooden chair

Once all the seat slats are in the right place, I drill a couple of guide holes in each end of each slat, and I screw them.

As you can see in the picture, I decided to take both armrests apart so I can work easily.

And once I inserted all the screw, I can take the spacers off.

And now, to finish with this Adirondack chair assembly, I could assemble the armrests once again. But I still have to sand all the pieces. And then I will apply a couple of coats of wood stain and protector.

Adirondack chair finnishing

The Adirondack chair is a wooden chair that will pass a lot of time in the garden, under the Sun, and probably under the rain. That is why we must treat it with a good waterproof wood stain and protector.

Number all the back and the seat slats

Then, first I will number all the back and the seat slats. And then I will dismantle the Adirondack chair. Luckily once all the screws holes where made, it will be very easy to assemble this wooden chair once again. The only problem is to discover the right position for each slat. That’s why I number them.

Then, I number the slats and I dismantle this garden chair.

Countersink the screws holes

Now, first I countersink the screws holes. This will help to level the screws head with the wood surface. But I must be careful and make sure I only countersink the holes that will accommodate the head of one screw. It would be a good idea to mark them with a pencil before I dismantle the chair.

Before sanding I decided to round some corners so this wooden chair looks more nice. In particular I will round the armrests corners (except the part I screw against the back legs), I also round the armrests supports corners (except the part I screw against the front legs and against the armrests), and finally I round the outside corners of both, the back and the seat slats.

I use my homemade router table to round the corners. But I must be very careful, because it can be dangerous to route the small pieces. I should use some kind of support or pusher to route the small pieces.

Round the armrests cornersRound the armrests supports cornersRound the corners of the the back and the seat slats
Sand all the parts of the Adirondack chair

Now I can sand all the pieces of this wooden chair. I use medium grit sandpaper and fine grit sandpaper.

Apply two coats of waterproof wood stain and protector

And finally, I can apply the waterproof wood stain and protector. When we apply the first coat it doesn’t look very nice. But when we apply the second coat it makes uniform, and we don’t see pronounced brush marks.

I apply the first coat. I wait until it is dry. I light sand with fine grit sandpaper. And I apply the second coat. Like this I get a nice and smooth finish.

When the waterproof wood stain and protector is dry, I can assemble the Adirondack chair. And I can enjoy sitting on it under the Sun.

As you can see, it can be complicated and hardworking assembling an Adirondack chair for the first time. And if we count all the time and hard work we need to make all the wooden pieces, we will realise we need a lot of hours to make this Adirondack chair. But if we think about all the years we will enjoy this garden chair, if we decide to make one, it is worth the effort to go to a lot of effort.

Assemble the Adirondack chairWooden Adirondack chair

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