how to build an a frame
TRANSCRIPT
How to build an A Frame
to measure contours
Pictures courtesy of the Permaculture Design Course 2012
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.
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?