How to build an A Frame

to measure contours

Pictures courtesy of the Permaculture Design Course 2012

Take two large poles

Mark the sticks about half way

down.

Attach the tops together. We used nails, but you could

also tie them tightly.

Make sure ends stay even

Attach the 3rd stick---we used our free Spenard Builders’ yardstick.

Attach string from the top

Tie a big rock to the bottom of

the string so it hangs

below the cross piece, but doesn’t

hit the ground.

You can barely see the rock!

Look for level ground.

Mark each foot very carefully with

small sticks.

Draw a mark where the string

crosses the crossbar.

Then turn the A Frame around and place each foot in the other

foot’s place. Mark the spot again.

Rarely do the two marks match.

Find the mid-point of the two marks.

Make a large mark there.

THAT is your LEVEL MARK

Now you can move across the landscape moving the A-Frame corner

to corner.

That is: one foot stays in its place while the other is rotated out to where

you believe level ground is.

When the rock stops moving, the string should be at the Level Mark IF the land

is level.

If not, move that foot over a bit!

If you want the water to move ever so slowly down slope, you can

give it a 1% - 2% slope.

Who’s math smart??? How many quarter inches would that be on the yard stick?

As the line meets the Level Mark, put a stick in the place where the

foot of the A-Frame was.

When you finish, you will have your contour measured.

Advantages: you can do it alone.

Disadvantages: it takes a long time to wait for the rock to balance.