Normally guys use a power planer to mow down the foam to the thickness you want.
By hand, the trick is to shape the stringer down first with a trim plane, then level the foam to the stringer with a G-rasp or shaping rasp.
Normally guys use a power planer to mow down the foam to the thickness you want.
By hand, the trick is to shape the stringer down first with a trim plane, then level the foam to the stringer with a G-rasp or shaping rasp.