Replies

1. 
   AitchKay | Nov 25, 2008 06:44pm | #1

   I built a serpentine retaining wall last year that was about 90' long.

   I used a 1x4 as a trammel to lay out the curves.

   I drilled a hole in the end of the board to receive a funnel, and several holes the size of my form stakes along the length of the board for various different radii.

   To use my layout jig, I stuck my funnel into the end of the board, filled it with flour, and pivoted the board while tapping it with my hammer.

   The customer and I stepped back, looked at it, and where he wanted to make changes, I erased the line with a lawnmower.

   When we were satisfied, I made the line permanent for the excavator with paint.

   I don't know exactly what you're doing, but you probably want a curved slab. Use the center-pivot technique above, skip the flour, and locate form stakes (these are usually about 3/4" dia. x 2' long) directly off of the pivot board. Bend your form wood around these stakes. If you have a tight radius, multiple strips of 1/4" tempered Masonite work well.

   If the slab will not be visible, you're ready to pour -- maybe grease your stakes so that the concrete won't stick. The notches left by the stakes won't ever be seen.

   If your slab will be exposed, now go back and drive wood stakes on the OUTSIDE of the form, screw your form boards to these, and then remove the metal stakes.

   AitchKay