Sometimes it's hard to locate the old style leading edge material like that used in Ringmasters and FliteStreaks.  If you can find them you take what you can get as far as weight.  A lot of the time they are warped. 

If you are fortunate enough to have a fairly robust router and table you can make them as in the example.

Not sure if this should go in this section but Robert can always delete it.

MSN will not allow hot linking so you can see the diagram here:

http://groups.msn.com/NorfolkAeromodelers/howto.msnw?action=ShowPhoto&PhotoID=107