we set out a garden every year an its always a fight to keep the birds an deer from clipping our planets, use some kinda grease on all the surfaces that see contact an shafts an bolts an hopefully it will hold up. it may be changed at some point, cause all test thus far has been in door so its not seen a lot of run time at this point. at the moment i have a solar panel charging 2 18500 batterys in parallel an a step down convert going from the batterys to the motor. the motor is out of a power wheels so there might end up being a version that uses the gear box from the power wheels but for now this works. would be better off using a motor that isn't high rpm tho cause the motor out of the power wheels is 6v 14000 rpm an im running it at low voltage to keep the speed down but any lower than 1.8 volts an its not enough for the motor to start so i have it set at 2 an it will start own its own now but runs quite a bit faster than i would like but im still going to put it out an start testing with it, the faster speed with just show signs of wear faster. i think you would be alot better off with a lower rpm motor i dont know for sure what speed would be best but im going to try buying a couple different motors that run at different speeds so i can play with it some but hopefully someone else can get some use out of it. the hole idea came from searching for a solar powered scarecrow an i stumbled across what looked like a bird house with this same mechanism right below the bird house so i just took that picture an guessed at the sizes an made this thing in tinkercad, it does look like a bird flapping its wings but im using it for the opposite, trying to scare birds out of the garden. if there isn't enough movement from the arms u might be able to drill some more holes in the arms an get alittle more motion out of the arms, but this is something ive not played with but once its up an running if it doesnt scare the birds i'll add more holes an see if that helps. the holes on the very end of the arm is for tying ribbon on to try to add that much more movement as the wind blows but do with them as u wish.