The only thing I have seen is to be sure the sealant around the hinge arms is good. If water gets in there, the lid frame will rust out. No bueno.
My screens are a mess. When I replace them, I will do it with something less brittle (or less likely to get brittle over time). I think the screens on mine are fiberglass. I may go with a softer mesh replacement.
The tent material needs to be kept clean. I have wiped down the material, inside and out, with soapy water (with a few capfuls of bleach thrown in for good measure). Came out beautifully. I would like to do that once a year. Probably happens once every three years.
Not sure what you can do with the torsion bar. There are bushings in the hinges. I don't think you'd want to grease them or anything. I guess if you wanted the torsion bar to live a long, happy life, you might store the lid in the vertical position, taking the twist out of the bar. Obviously, that's not practical; so, I just try to open and close it gently so as not to put any undue stress on the bar. They have been known to break...
I am anxious to hear of others' efforts to keep up their FP's...
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