I have always used denatured alcohol to clean my r/c parts. You can get it at most hardware stores and it's alot cheaper than nitro pray cleaner. You will need to get a spray bottle since the D/A comes in gallons and quarts. You can use it to clean anything from metal to plastic ( excpet elec. parts of course). It dries really clean too, Wd40 doesn't. But WD40 does work as a great lube.