Do NOT use the steel wing hold-down screws included in the kit
Was just browsing the threads regarding the Goldberg Cub crashes. Just a word of friendly advice: Do NOT use the #6 x 1-1/4" metal wing hold-down screws included in the kit. Use 1/4" NYLON BOLTS instead. I witnessed two Goldberg Cubs destroy themselves by ground looping on takeoffs. The crashes literally destroyed the cabin structures. In both instances the Cub's wings were fastened with the kit-included steel screws, so the cabin structures absorbed the total impact because the metal screws did not break. As an alternative, I suggest using 1/4" NYLON bolts instead. Nylon bolts are terrific for wing hold-downs because they will typically snap on impact thereby minimizing structural damage. I know -- I've done it. Touched down with wing tips on landing which caused the airplanes to flip. Always pleasantly surprised that the nylon bolts absorbed most of the impacts by snapping in half rather than passing the stress to the surrounding structure. The cabin structure of the Goldberg Cub is notoriously weak. Using nylon bolts to attach the wing may not prevent crash damage but, I believe, it will help minimize it. Virtually everyone our club uses nylon bolts for their wing hold-downs. Just thought I'd just pass this along. Thanks.