4. As an added ‘bonus’ I made sure that the two points of the A-Frame were a metre apart at the bottom, so I can also use this as a ‘metre measure’. This uses the permaculture design principle of ‘Stacking’ – I get two useful functions out of the one tool!
6. I find the mid point of the top cross bar and tie a long piece of string to it. This is going to be the ‘plumb line’ – it will have a weight attached to it.
7. After attaching a rock as the weight, I find the centre point of the frame and mark it – this is the point at which the stone hangs when the frame is exactly level, allowing you to map your contours.
8. For more info about using and calibrating an A-Frame, check out this post.