How to make a simple and lightweight folding chair from profile sections

How to make a folding chair from a profile

We cut 2 pieces of length 80 cm and 50 cm from the profile square pipe.

We mark the centers of the through holes along their longitudinal axes, measuring 25 cm from one edge on long pieces, 3.5 cm from the other, and 28 cm and 3.5 cm on short pieces, respectively.

We draw transverse lines on long workpieces at a distance of 42 cm from those sides from which the holes are 25 cm apart. We draw inclined straight lines to them at a slight angle and make cutting.

We join short and long sections along the inclined ends and weld the joints. We clean the seams with a grinder. We connect the blanks from the profile pipe to each other using bolts, nuts and washers.

Between the ends of the internal blanks, we install crossbars also from a profile pipe on the short side at the level of the ends, and on the other, slightly backing from the edges, and weld the joints. We also use a cross member from a profile pipe to connect the ends of long workpieces at the level of their ends by welding.

From the ends of the long workpieces, where the crossbar is welded flush, we measure 36 cm and put marks.We screw a nut onto the ends of a stud of a given length, place the nuts on the marks and weld them to the workpieces.

We insert plastic plugs into the ends of the parts made from profile pipes, tapping them with a hammer. We paint the frame of the folding chair using a spray gun.

We throw the ends of the durable fabric over the transverse elements of the chair frame and secure it with hems to the back and seat posts with pins passed through the hems on the side sections of the fabric.

At the place where the fabric transitions from the seat to the back, we make a transverse seam on the fabric and get a closed cavity through which we pass a pin, and screw the ends into the nuts that were previously welded to the elements of the chair frame.

When the chair is unfolded, the fabric, stretching, serves as a seat and back, and also gives it stability. When folding the chair frame, the fabric does not interfere with this, since its tension subsides.