ORIGINAL: Dr1Driver
Absolutely safe. They also look neater and are easier to maintain than rubber bands.
On a .40 size plane, the most you need on the wing is 10-32, unless you fly pylon. Drill and tap the bolt blocks with a 5/32" drill and a 10-32 tap. A #21 drill is actually the proper size, but the 5/32" works well and is easier to find. Soak the threads with thin CA, let dry. Re-tap. Do this again. The threads will never pull out.
On the landing gear, I'd use 4 10-32 or 3 (two in front, one in back) 1/4-20 bolts, depending on how soft your landings are.
Dr.1
I couldn't agree more on the nylon bolts for the landing gear. I used the three steel screws that came with the 4*60 kit and the first "hard landing" the landing gear came right off. along with the mounting and parts of the fuse. Replacing the stock landing gear with the Dubro somposite and useing four 10/24 nylon, the gear stays put but it will snap of if you run into a gopher hole which we have a lot of around the field. I know, we have a paved runway, but evey now and then, it moves from under the plane just before touch down, and then I find the gopher holes.
Don