iflynething

I actually do cut the dihedrial into the wing. I build the wing accord to the plans. Then I mount each wing half on a flat board and align the wing half on my 10" radial arm saw. I then raise the wing tip the appropriate amount and make the saw cut.
This makes a beautiful cut and there is no tearing of the balsa or what ever wood is used. This method works excellent on foam wings and there is no void between the wing halves when they are matched together.

Find a friend with a radial arm saw.

Good Luck

Lee