Building a stealth grow cabinet and wondering what I can use on the inside besides mylar? Its flimsy and looks like it might be a pain in the future if it falls or something.
Try Diamond film, but you better use a staple gun as I haven't found any kind of tape that sticks to it permanently.
Fix the Mylar to cardboard panels cut to suit, it's a lot easier to handle than sticking it to walls. Cut the Mylar about an inch oversize all round and stick to the back of the panels with double sided tape. Then simply stick the panels in place, again with double sided tape. Edit: nearly finished veg cabinet, just waiting for vent fan and 200w cfl.
I had a problem with the mylar woving alot with the breeze from the fan. Switched to the thick black and white (panda wrap) plastic sheets. Easier to work with and great at keeping light in. I have used the cardboard panels wrapped in mylar as well and recommend the 3m tape used for weatherproofing windows.