Foam Cutting Templates

The button labeled "Template Setup..." brings up a dialog box to set up a foam cutting template. All values in this dialog are absolute distances in the current units. The dialog is movable, and if "dynamic redraw" is set in your preferences, the main plot will redraw as you enter the data. So you can move the dialog away from the main plot and see what the template looks like as you change various values.

Template Height is the only required value to create a basic template. It is measured from the chord line down, so for instance to create a template with its bottom 2 inches below the chord, enter "2" in the box (assuming you're working in inches, of course).

Foam Block Height is optional, and simply draws a dashed reference line over the top, showing the outline of the entire foam block. It is measured from the bottom of the template.

Wire Kerf is the amount of foam removed by your cutting wire. Entering a value in this field modifies the lower foil surface in the template to correct for the horizontal undercut you would otherwise get.

To get this value accurate, you will have to carefully measure it with your particular cutting equipment as follows: measure the height of a block of scrap foam, then make a horizontal cut through it. Remove the whiskers, place the two pieces back together, and measure the height again. The difference from the original height is the kerf value to enter.

# Station lines specifies the number of evenly spaced vertical lines drawn across the template for reference while cutting. These are helpful for monitoring your cutting progress, particularly on tapered wings. The number you enter is the number of station lines you want beyond the leading edge. For instance if you enter 5, you'll get a line labeled "0" at the leading edge, then lines 1 through 5, with 5 at the trailing edge.

LE Ramp Length is the length of the "lead in" ramp lines, measured from the leading edge of the original airfoil.

LE Intersection is the distance back from the leading edge of the original airfoil that you want the ramps to intersect the foil surface.

Angle LE Ramps is a checkbox that specifies whether to angle the LE ramps to get a shallower angle of intersection with the foil surface. Note that the ramps will not be truly tangent to the airfoil surface, they are simply angled to reduce the angle somewhat.

TE Ramp Length is the length of the "lead out" ramp lines, measured from the trailing edge of the original airfoil.

TE Ramp Follows: Here you have three choices. The ramp can follow the upper surface, the lower surface, or the camber line.