Nope, never cleaned or boiled the cheesecloth. That is really only an issue if the cotton has been overly processed as far as I know. I use cheesecloth in all of my rba's too, and have never once boiled or cleaned it in any way. Just cut, install, and vape. I don't even let it sit and saturate as many people do (I've seen up to an hour!) once it LOOKS saturated (about 30 seconds) I start vaping. Never a burnt hit or a bad taste.