Constructing a grape trellis involves choosing a suitable location, installing main posts and anchor posts, installing support wires, and attaching grapevine catch wires. You need PVC pipes, a staple gun, anchor posts, a galvanized steel wire and a lightweight wire to complete this task; concrete is also handy.
When choosing a grape trellis site, be sure that the place is spacious enough to accommodate grapevines after they grow. The location should be open to allow the grapevines to access adequate sunlight as well. Once you've selected a suitable location, make the main posts by piecing the PVC pipes into sizes that suit the type of grapevines you intend to plant. Dig holes for the posts -- each 2 feet deep -- and leave a 15-foot space between holes. Set the posts in the holes, and secure them in place with the concrete before inserting the anchor posts.
To install the support wires, make a mark 3 inches from the ground on each of the posts, round the posts with the steel wire through the marks, and use the staple gun to secure the wire onto the posts. Mark 1 foot from the top of each main post, run the wire through the marks, and attach it in place with the staple gun. Then, secure the lightweight wire onto the posts in the space between the support wires to complete the process.