ORIGINAL: BMatthews
Alasdair, the 240xx series are a lower or neutral pitching moment style and should be fine for this sort of use. But I agree that making the fore plane with a postive camber airfoil would be a wise option. Tim something like a NACA 2410 would not be a bad option for the foreplane. Or on a smaller model just use 1/8 to 1/4 sheet surface depending on the model size and sand in a reasonable approximation of a Clark Y.
Yes I realise that the 5 digit series were designed for a low pitching moment, but it is still there, and still negative, so it loads the tinyforeplane a little
Compufoil gives Cmo as -0.013 and zero lift at -1.09 degrees
For a small electric model of the Shinden I would be tempted by something like an Eppler E182, but thickened up towards the root. It has Cmo of +0.006 and zero lift at -0.29 degrees, but its 1.7% camber will give a better CLmax than a symmetrical section
just BTW, I'm thinking of changing from symmetrical to NACA 130xx for my next Candel development