Not too long maybe 30 mins and if you want a good reliable mod you can't go too far wrong with a nemisis or a stingray make sure you get the magnet switch for the nemisis tho if you get one and make sure you know what your batteries can do you may have noticed I was using a 26650 version of the nemisis on that build which yes was the right size for the 28mm doge but also because the build was 0.16ohm and only my 26650 batteries can handle that kind of resistance safely if you have one of the apps you can check if your build is going to be safe