I often see in dechuntion, fokes trying to find moter shafts. So heair is how to make em. Say you need a 3.17 shaft and can,t find one. Buy a peace of 1/8 spring wire, you'll also need a sheet of 400 wet or dry paper and a drumel tool with a thin stone cut off disk. Cut about 3mm off one end of the wire to leave a true size end. Use the 400 grit paper back and forth on wire while turning constantly with other hand. Check fit often with bearing, you want to be able to push bearing onto wire and feel resistance for a lenth of wire as long as the shaft needs to be. Use the cut off disk to cut grove for retaining clip, and flats for set csrews. Cut shaft off wire, chanfer edges and your ready to go.
For harder shafts you can buy hardended doll pins or reamer and drill blanks from an industrial supply Co. such as MSC.
Your first shaft may take several hours to make if you have to paper it down.
Use a tuch of lock tite or CA glew on screw threads on final assembly. Rool shafts on a peace of glass to check for stright.
AND IF YOU HAVE TIPS ON HOW TO SAY MAKE A CANAPY FROM SAY A PLASTIC BOTTLE OR REPAIR PATCHES FROM ALUMIUM CANS PLEASE POST