Use a measuring tape to find the middle of each dowel. Drill a hole large enough to easily fit the bolt at this point through each dowel. Find the center of one end of each dowel by drawing perpendicular lines across the diameter, making an “X”. Drill a small hole at the center.
Place a washer on the bolt. Thread the bolt through the hole in the middle of one dowel. Put the bolt through the eye of the eye-hole bolt. Thread the bolt through the middle of the second dowel, so that the eye-hole bolt is sandwiched between the two dowels. Place a second washer on the end of the bolt before capping the end with the acorn nut.
Thread the eye-hole through the hole in the middle of the third dowel. Place a washer on the end and cap with an acorn nut. Tighten both nuts with a wrench.
Cut an equilateral triangle with sides approximately 14 inches long from the canvas. Cut another three small equilateral triangles with sides approximately three inches long from the remaining material. Sew the three small triangles onto each corner of the larger triangle. Fold over each side of the large triangle about ¼ inch and sew in place.
Make a small hole through both layers about one inch in from each corner of the canvas triangle. Insert a grommet into each hole. Secure in place with the grommet setter and hammer.
Insert the wood screws through the grommets. Screw each screw into the hole at the end of each dowel, securing the canvas seat in place.