I have been building a mash tun out of a 150qt cooler. The bulkhead I bought from my homebrew store was too short, so I improvised with some brass pipe. The piece of pipe is a bit too long now, as the threads don't get close enough to the cooler walls, I have used a handful of washers, and o-rings. I am still worried it might leak into the cooler. At Home Depot, an employee steered me towards an epoxy to seal it up. I am worried that it will leach into the wort, but the employee said it was used for drinking water. Has anyone else run into these problems, or used an epoxy to seal the mash tun? Also would anyone have any suggestions for the build?