I'm starting to get a little odor that I think is leakage from my primary chamber door gasket. The sealing surface is baked creosote rather than ceramic/fiberglass rope at this point. It's hard, black, and smooth with no resilience at all. I'm thinking it may be time to replace the gasket. Since this seal has to be perfect and it's been years since I've done one, I'm looking for suggestions on the best way to do this - materials, techniques, tricks, and so on.