I'm putting together my 2-tier brew rig and wanted to upgrade my valves and tubing to 1/2". I looked at several of the online cooler bulkhead fittings and wasn't sure how well they'd work with my 10g Rubbermaid coolers, which have walls at the spigot area that are very thin. Also, if something broke it'd be nice to have the option to just run up to the local HD or hardware store and get a replacement. Anyways, after purchasing the parts I realized I can't find SS fender washers at any place in town that will fit around a 1/2" pipe nipple; the OD of the nipple is ~13/16". I also searched online but didn't find anything other than custom order, which needs to be ordered in bulk.
Can I just drill out some of the SS washers I already have using a step bit? Or maybe there's something else I can use that will be stiff enough to seal the o-ring to the inside of the cooler wall, plastic gaskets with a metal spacer or nut or something? Anyplace online you know of to order something that would work? Any thoughts or recommendations are appreciated.