Hello to everyone. I'm in Amman, Jordan. Began incorporating permaculture principles and designs on my property a few years ago. Now I want to build a swale on my land and need someone to tell me how to build and calibrate an A-frame. Let me hear from you all.
Hi Cheryl and welcome! This article not only details how to construct an A-frame level, it also includes a how-to build a bunyip level: https://www.harvestingrainwater.com...ater-Levels-and-A-Frame-Levels-Appendix-2.pdf The important part in calibrating an a-frame level is having a known level spot to place the two legs so that you may correctly mark the point at which the weighted string intersects the cross member. A builder's level could help you find such a spot ... or also a small bunyip level!
Hi Cheryl I am in Jordan right now, I was in Amman today, I usually get a big letter A welded up in one of the local metal workshops using thick concrete re-enforcing steel used in concrete, usual 1.5 to 2m across the base, it does not have to be a perfect A close is fine, then get them to weld a little tag at the just under the top of the point of the A with a little hole drilled through it to tie the string onto, tie on the string with a weight on long enough to go past the cross bar but above the ground. The you have a rugged long lasting survey A-frame level.
Stand your new rugged A-frame level on a level floor mark where the string hangs next to the cross bar, mark the floor and turn it around and switch the leg positions on the marked floor and check the string where it hangs again if it is in the same spot you are on a level floor so mark the cross bar with a metal hacksaw, if it is different you are not on a level floor and half way between the two marks on the cross bar is level so mark that point with the metal hacksaw and you are done. Happy Swale Surveying