Introduction: Lifeguard Chair From Recycled Lumber

About: Educator, entrepreneur, photogeek.

The inspiration for this chair came from seeing one on a pier at Lake Tahoe. It’s big – seating two pretty comfortably – and tall, affording a nice view along with protection from cannonballs and wet dogs.

This one is made from lumber recycled from a redwood deck we ripped out. The weathering, stains and screw holes all add to character of the chair even after rigorous sanding on the seat, footrest, arms and back. With ‘free’ lumber, the cost for this chair was two boxes of screws, some glue and sand paper. (And in my case, a belt sander – but that’s an investment, right?)

Though not particularly difficult to build, it did take a few days and some table saw skills. There are a number of angled cuts and a couple of dados to contend with. I would not recommend taking this on without a table saw, a belt sander and a good drill.

The plans were created using SketchUp from photos taken of the inspirational chair, with a few modifications for aesthetics and ease of construction. The SketchUp files are included here, if you don’t have the program you can download it for free at sketchup.google.com . Description of the files is at the bottom of this step.

MATERIALS
It's important to note that a 2x4 is actually 1.5" x 3.5" - the plans assume this, and if you're using recycled lumber you'll need to take that into account .
2x4 lumber - 92 linear feet (can be done with12 8' boards if you lay it out carefully)
2x6 lumber - about 6 feet for the armrests
2.5" deck screws - two boxes (about 150 screws)
2" deck screws - 18
Glue - outdoor grade wood glue

TOOLS
Table saw - with tilting blade for some 15 degree cuts. Also a set of dado blades unless you're using a router for the rabbet cuts.
Hand saw - there are a few cuts that are just easier to do by hand.
Jig saw or band saw - for rounding the arms. Optionally you can approximate with the hand saw and sand it down.
Belt sander - essential, there's a lot of sanding to get the sitting area smooth, especially if you're using recycled lumber.
Drill - you need to put in about 150 screws
Drill press - optional, but makes for beautifully aligned pilot holes
Clamps - at least four hearty clamps for holding the legs during dry assembly, also used in assembling the seat, footrest and back.
Pencil - cheap but effective.

SAFETY
Protect your eyes and ears when using power tools!
Gloves or Epsom Salt - your choice for dealing with splinters. I started with Epsom Salt, which is great for removing that nasty splinter that goes in your finger all the way to the nail. Then I changed to gloves. I recommend starting with the gloves.
Mask - wear it when sanding, or cough a lot.

PROCESS
The chair has three main parts - the backrest, seat and footrest, with the arms, legs and cross members holding it all together. We will build it in that order. I highly recommend reading and understanding the whole process first.

SKETCHUP FILES
There are four versions of the model in SketchUp included below. They each contain all the parts, but in different configurations for your (and my) convenience. The basic model has everything you really need.
lifeguard_chair_basic.skp - The fully assembled chair with height dimensions (as shown in the 'Main Assembly' step).
lifeguard_chair_boards.skp - One possible layout to cut the pieces from 12 eight foot 2x4s and one six foot 2x6.
lifeguard_chair_explode.skp - Exploded version showing the main parts of the chair (as shown in the last image of this step).
chairDetails.skp - Each main assembly with some notes (as shown in steps 3, 4, 5, 6, 8).

Step 1: Prepping the Lumber

Our old deck was made from 2x6 redwood boards, which had been torn out and stacked in our side yard. After selecting the best boards and air drying them thoroughly, they were cut down to 2x4s (which are actually 1.5" x 3.5"). 

1. Quickly sand to remove loose dirt and debris. A more rigorous sanding will happen later, but it's necessary to get the sides and edges clean for running through the table saw. A hand sanding pass with 80 grit paper is adequate.

2. Trim one edge straight. For trimming down 2x6 lumber (which is 1.5" x 5.5") set the fence to 5 1/4" and rip the length of the board. This will trim off about 1/4" and give you a clean straight edge.

3. Set the fence to 3 1/2", flip the board over and rip down the other edge. You'll now have a 2x4 with two clean edges.

4. Now's a good time to do a real sanding pass with the belt sander - the long boards make easier setup that a lot of short boards. Sand according to how polished you want your chair to look. The seats, back, arms and footrest will be sanded once assembled, so you're determining the look of the rest of the chair now. If you're going to paint it or using new wood, spend time getting a nice finish now. If you're going for a more recycled look like this chair, a pass with 80 grit and then 120 grit should do the trick. The goal is to clean it up but not remove the character that came with the prior use of the wood.

5. Cut 2x4s to approximate lengths (see plan). NOTE: cut the cross members and back slat a few inches too long - you'll custom fit them later and will need the latitude in length.

Step 2: Assemble the Backrest

LUMBER
9 back pieces - 21 1/2" long (don't cut the angled end until after backrest is assembled)
Top piece - 31 1/2" long, 1 1/2" square
Back slat (arm support) - 38 1/2" long (but rough cut a few inches longer)

PREP
Drill pilot holes in the top piece for the screws that will hold the back pieces. You will use two screws for each of the nine boards. A good technique for marking where the pilot holes go is to lay a piece of masking tape on your wood, then measure and mark on that. The holes start at 7/8" from each end and are spaced 1 3/4" apart, centered along the width.

Tilt the blade on your table saw to 15 degrees for the next few cuts. Cut that angle off the top of the back slat - this will be level with the backs of the arms when the chair is assembled and the back is tilted. 

While your table saw is set up for the 15 degree angle cut, you should cut the back support for the seat and the top of the back piece of the footrest. (See Steps 3 and 4 for proper dimensions.)

Leave the blade tilted for now, you'll do one more angled cut after the back is assembled.

ASSEMBLY
Lay the nine back pieces side by side and even up the top edges. Clamp them together to hold them securely while you glue and screw the top piece to them.

The back slat spans across the back and holds the back of the arms. It is best to fit this accurately during final assembly rather than trusting the measurements on the plan (things always shift a bit). Rather than attaching the back slat now, put a few screws into a piece of scrap wood to hold the assembly together (see picture). 

Cut the 15 degree angle at the bottom of the back, where it will attach to the seat, cutting across all nine boards at once.

SANDING
Sand the back to make it smooth and splinter-free. I started with 80 grit sandpaper on the belt sander and finished with 120 grit. If you're going to paint it you'll want to go even finer, but 120 grit gave a smooth enough finish for the raw wood. This takes awhile, even with a belt sander.

Make sure there aren't any potential places that can become splinters later - I had to hand sand a few old screw holes left from the deck.

Hand sand all the corners and edges. This gives the chair a softer weathered look, feels much nicer, and prevents nasty splinters.

Step 3: Assemble the Seat

LUMBER
6 seat slats - 30" long
Front and Back - 31 1/2" long
2 sides - 21" long
Backrest support - 31 1/2" long with 15 degree angle cut.

PREP
Cut the rabbets in the two 21" sides. A rabbet works like a shelf to hold the slats in place. The simplest way to cut them is to use a dado set on your table saw. The dados should be set to be 3/4" high. Since the full rabbet will be 1 1/2" wide (the width of a slat) you'll need to make multiple passes to get the full width. You want a flush fit, so once you're close to the right width keep testing with a slat and work your way to perfection. Routers also work great for doing rabbet cuts. You could alternately do a couple of passes with your regular saw blade set to 3/4" high and then 1 1/2" high. 

You should have cut the 15 degree angle on the backrest support during the prior step, but if not, do it now.

Drill pilot holes for the screws that will hold the slats along the sides. You will use two screws for each end of the six slats. The holes start at 7/8" from each end and are spaced 1 3/4" apart. They should be centered in the middle of the rabbet (3/4" from the top edge of the side). 

Drill pilot holes in the backrest  support. The backrest has nine 2x4s, so you will need 18 holes along the side with the angled cut, and 9 holes along the top to screw it into the seat.

Drill pilot holes in the front and back pieces for attaching the sides. 

ASSEMBLY
Dry fit everything together to test. You may need to trim one of the seat slats a little narrower (3" instead of 3.5") to allow a bit of room between each of the slats for expansion. 

Glue and screw the front, back and sides together. Screw the slats into place. It isn't necessary to glue the slats - they are plenty secure with the screws and rabbet cuts, and without glue they'll be able to move a bit as they expand and contract with the weather.

SANDING
Before you attach the backrest support piece, sand the seat to make it smooth and splinter-free. The belt sander makes this a breeze, but you may have to hand sand a few areas if you're working with weathered wood.

Hand sand all the corners and edges.

FINISH
Now glue and screw the backrest support on. It's easiest to glue and clamp it first making sure everything is aligned, then screw it down. Any glue runout can be cleaned up with a damp towel.

Step 4: Assemble the Footrest

LUMBER
4 slats - 30" long
Front - 31 1/2" long
Back - 31 1/2" long with 15 degree angle cut along the top.
2 sides - 39 5/8" long

PREP
The back piece needs the top cut off at 15 degrees, which hopefully was done in the prior step when the table saw's tilt blade was set up.

The back edges of the side pieces need to be cut at an angle of 15 degrees to match the angle of the legs. 

Cut the rabbets in the two sides. These are a little trickier than the seat, as they only extend 14" rather than the full length of the side. I used the dado blades, as before, but when stopped part way they leave an arc rather than a perfect square so the remainder of the rabbet needs to be cut out by hand. A hammer and chisel works perfectly for this.

 Drill pilot holes for the 16 screws that will hold the slats along the sides. 

Drill pilot holes in the front and back pieces for attaching the sides.

ASSEMBLY
Dry fit everything together to test. You may need to trim one of the seat slats a little narrower (3.25" instead of 3.5") to allow a bit of room between each of the slats for expansion.

Glue and screw the front, back and sides together. Screw the slats into place without glue.

SANDING
Sand to the same body-friendly smoothness as you did the seat. People may choose to sit here, and it will certainly have bare feet on it. Hand sand the corners and edges as before, also.

Step 5: Armrests

LUMBER
2 2x6 armrests - 28 3/4" long

PREP
The armrests are cut from 2x6 lumber, which is 1.5"x5.5" in actual dimensions. 

Mark a semicircle at one end with a 2 3/4" radius. Using a jigsaw or band saw, cut the end as round as possible. If you don't have one of those tools, you can approximate it with a number of handsaw cuts. 

SANDING
Head to a good sander and finish the end to a smooth round arc. The best tool is a table mounted disc sander (see picture).

Sand the top of the armrest as smooth as the seat, footrest and back. Round off all the edges manually, as before.

ANOTHER CUT
At the other end of the armrest, measure 3.5" along the back and mark that point. Then measure 8" up the edge and mark again. Draw a line between the two marks. Now figure out how to make this cut.

I tried this cut first with my jig saw and it was a resounding failure - don't bother trying it. The blade on a jig saw is too flexible to make this cut straight vertically. If you have a band saw this cut is a piece of cake, or you can certainly cut it by hand and do some sanding to clean it up. My solution was to screw a piece of oak the width of the table saw's miter gauge channel to the bottom of the armrest. It was screwed on parallel to the desired cut line about 5" out (the distance from the channel to the blade). This guided the armrest straight through the blade at the desired angle with a nice clean cut. Yea!

REPEAT
I cut and sanded one arm before I made the other. This allowed me to use the first as a guide, and happily to make all my mistakes only once. Remember that the second armrest is a mirror image of the first, so pay attention to which side of the lumber you want up.

Step 6: Prep Remaining Parts

LUMBER
4 legs - 49" long
2 cross members - over 35" long (will be cut down during assembly)

PREP
The ends of the legs need to be cut at 15 degree angles. Start by cutting one end, then measure up 48" on each edge - this should be where your other angle is. The finished leg should be a parallelogram - meaning that the two opposite sides should be parallel. Use the first leg as the pattern for the other three legs - the exact size of a leg is less important than all the legs being equal. 

Nothing to do on the cross members now, as they will be custom fit after the rest of the chair is assembled.

SANDING
Sand as is appropriate for your project. I cleaned my chair legs up but not to the degree of the seat. 

Sand the edges smooth to match the rest of the project.

Step 7: Main Assembly

Bring all the parts together on a level surface. You'll need your drill, screws, clamps, glue, measuring tape or angle, pencil and a level.

LEGS, SEAT AND FOOTREST
Using the dimension drawing (image 3 of this step), measure and mark the legs with the pencil where the footrest and seat will be. Clamp the footrest and seat into place. Use the measuring tape, the level, your eyes and your excellent judgement to make sure everything is even and level. Check to make sure the tops of the legs are level and even by balancing the armrests on them. Once you're satisfied, drive a couple of screws part way in on each joint to hold it together temporarily.

Remove one leg at a time, apply glue generously to the joints, and reattach the leg with four screws at each joint. (I clamped a spare board to the chair to act as a fourth leg before I removed each leg.) Check to make sure nothing has shifted and do another leg. Repeat two more times. 

BACKREST
I made a jig to hold the backrest in place while I measured for where the back slat would go, and for when I attached the back. The jig is made from two 2x4's screwed together at a 15 degree angle. 

Using the jig, clamp the backrest in place. Position the armrests in place and mark where the bottoms of the armrests cross the back - this is where the top of the back slat will be. (If the temporary back slat is in the way, remove it carefully.)

Remove the backrest and attach the permanent back slat. I used two 2" screws for each of the nine back pieces - I was concerned that a 2.5" screw could go all the way through the back if I drove it in too far. NOTE: The back slat should have a 15 degree angle cut off the top of it, make sure this is properly aligned when you attach it. Also, the back slat should be too long, make sure to have extra length on each end - they will be trimmed after attaching the back.

With the permanent back slat in place and the temporary one removed, use the jig to clamp the backrest back onto the chair. Screw it to the chair with another 18 screws horizontally through the backrest support on the seat.

ARMS
With the backrest in place, it's a snap to attach the arms. Line up the back of the arm with the back of the back slat, then glue the joints and put a couple of screws down into the back slat and each of the legs (six screws, total, for each arm).

Grab your hand saw and cut off the excess back slat, making it even with the angle of the arm (see pictures).

Hand sand any sharp edges.

Step 8: Cross Members

The cross members are the only tricky part of the build, but they are necessary to add rigidity and strength to the chair. They attach from under the the seat on one side to inside the footrest on the other side.

Ideally, they would match the dimensions in the plan, but even a 1/4" variance in your build would cause them not to fit properly, so we cut them custom to the final assembly of the chair. Regardless of variance in your chair, the two cross members should be the same dimensions, so make one and use it as the template to cut the other.

The cross members are angled at about 32 degrees, so make the first cut (noted in the first diagram) at that angle (the interior of the angle is noted on the diagram as 122 degrees, which is 90 + 32). Then measure up the cut edge 2" and draw a right angle line - make this cut second. This end of the cross member will fit under the seat (see second diagram). 

It would be really nice if you could dry fit this piece somehow and mark where the next two cuts at the other end of the cross member go, but that isn't possible. After trying all sorts of methods, I finally settled on just making the third cut (which butts against the footrest side) a little long, dry fitting, and trimming down until I got the proper fit. The goal is to have the bottom of the cross member even with the bottom of the seat and the top of the cross member even with the top of the footrest.

Once you have them cut to size, glue and screw them into place. The back cross member goes all the way back, and can be screwed from the inside to the back of the seat, and from the outside to the side of the footrest. The front cross member's position isn't critical, but should be as far forward as you can put it, but behind the front legs and comfortably out of the way of your feet.

Let the glue dry, grab a cold drink, and have a seat.

Step 9: Closing

If lifeguarding isn't your thing, this chair is a comfortable place to read, make some phone calls and enjoy the sunshine. It's more of a yard throne, really.

Enjoy! And send me pictures of yours!