The best fix is to go to the hardware store and get some 4-40 Allen screws and locknuts,washers,etc. Drill all the way thru and use them. Some stores have all the metric screws also. As an added hint Lowe's also sells blind nuts in their specialty fastener dept. I am lucky because we have a complete selection of metric screws at work. I am able to use metric just as easy as SAE. Nothing says you have to use what came with the plane. Doesn't take much to hold a small motor on. Only things we can't change are the laws of physics! ;-)