How to make a Concrete Chair

The Plans and the Material Requirements. 

Below are the plan drawings with the material requirements listed below.

For this project you will need…

For the sides of the form
12ft of 1 1/2″ x 3 1/2″ lumber.

For the back of the form – Plywood (at least 1/2″ thick)
one piece 21 1/2″ wide by 15 1/2″ long
one piece 21 1/2″ wide by 16 1/2″ long
one piece 21 1/2″ wide by 23 1/2″ long

For the front of the form – Plywood (at least 1/2″ thick)
one piece 21 1/2″ wide by 20″ long
one piece 21 1/2″ wide by 18″ long
one piece 21 1/2″ wide by 20″ long

Also, three pieces of plastic sheet the same width and length as the front plywood above.
The plastic sheet can be any thickness (for example 1/8″). Its sole purpose is to give the concrete a smooth finish.

For the top of the form – The stop end
one piece of 1″x6″ board 21 1/2″ long

Reinforcing steel
30ft of deformed (ribbed) reinforcing steel rod #3 rebar (3/8″ thick).
You can find more information about reinforcing steel here.

Concrete
You can make mix your own concrete using cement, sand and gravel. For information about how to mix concrete click here.
Alternatively you can buy bags of cement, gravel and sand (or similar type of aggregate) already mixed, which only require the addition of water to make concrete. I used seven 80 lb bags. You may need more or less depending on the size of the footing hole.

Other bits and pieces
Screws to hold the form together, tie wire to hold the reinforcing steel together, some wood (plywood or board) for the form bracing, and a load of blocks to pack the chair up and for form strengthening.