We purchase powered lead to add to polyester castings for "hidden" weight. Suspended in the resin it hardly gives an indication when the casting is tested for lead. I wouldn't recommend trying to use it simply glued in place. Instead, go for size 8.5 steel shot. It's small enough to fit in any nook or cranny. You can buy a 25 lb. bag cheap at any pawn/gun shop. That much should last a lifetime. - Al Westerfield