First impression is you do a great job of establishing the narrator as a character quickly. Even without the "I"s, it’s clear that this is a subjective view. I’m still a little iffy on “anyhoo,” but it fits the character so I’ll suck it up.
Spelling quibble: Did you mean “tungsten?” Grammar quibble: In the third paragraph, you should use a semicolon after “tug” or change the sentence around a bit, because it almost looks like the seat is talking.
“Quietly rocking” seems largely unnecessary, too – couldn’t it just be rocking? If he’s on a lawn chair in midair, I can’t imagine him noisily rocking – the use of “quietly” doesn’t really further specify the action.
Overall, very good. Aside from those totally meaningless points, it’s a very solid microfiction: the arc of plot is perfect for the length and the character is well-described (although I don’t get much of a sense of him beyond “old guy”). The descriptions, sentence structure and overall vocabulary are stellar.
I like how your character is pretty much established within the first few lines. The syntax and diction are immaculate (I haven’t found anything to complain about!) and convey the light-hearted mood well. Personally not a favorite piece, but a good piece of work nonetheless!