I know this has been discussed before, but I have a thought or two, and would like some opinions.
First, I really don't like the idea of wrapping the side panel at the bottom of the frame over the floor (i.e., the floor sandwiched between the thin side panel & the frame). It would definitely be visible from the side of the car (my alloy body panels won't be painted) as a step, of sorts, and would look unfinished IMHO.
The thought I had was to trim the floor panels by 1/2" around the outer edges (only where the alloy side panels will wrap around the bottom of the frame in the cockpit area), so both the floor & alloy panels will have 1/2" each for attachment & would butt up against one another along the underside of the outer bottom frame tube.
To preface, my floor is 1/8" hard aluminum, currently held in place with a total of 28 1/4"X20 allen-head stainless steel countersunk bolts, through reinforcing plates welded around the inside of the periphery of the floor area, secured with S/S nuts. Of course, I plan on using a sealant or construction adhesive to seal the floor, separate the aluminum from the (soon to be 2-part epoxy painted) frame, and to possibly add a little structural rigidity. I don't know what alloy the floor is made of, but it's VERY hard & tough. It's anodized, and hard enough that I went through 7 bimetal hacksaw-type fine tooth jigsaw blades cutting it. When you tap it with a hammer, it doesn't go "tink" like aluminum usually does...it goes "taaaannnnggggg" like a bronze bell. and keeps ringing for quite awhile.
My buddy doesn't agree that my floor attachment plan is strong enough. To attach the floor in his Locost, he's using 48 5/16"X28 bolts & nuts, structural aircraft adhesive, and a couple of hundred Cherry-Q rivets to secure his floor.
Personally, I think that's a bit overkill, and is likely adding weight & reducing strength in the main frame tubes by drilling hundreds of holes in them, but that's just my opinion.
Should I also add rivets, as well as the adhesive & bolts, to secure my floor, or do you think it will be strong enough with my existing plan? I should add that, with just the bolts in place (most of 'em, anyway, and none of them tight yet) I can jump up & down in the car without the floor flexing (I'm no lightweight, either, at 6'2" & 210 lbs.). I'm thinking that with the rest of the bolts in place, plus a structural adhesive, it should be plenty.
The alloy body panels will likely also get some structural adhesive, as well as some copper rivets to hold the bottom of the panels in place (although I'm not certain even these are necessary with the structural adhesive).
My plan was to drill as few holes in the frame as possible to retain the structural integrity of the steel, and so far, I don't have a single hole in any of the structural parts of the frame (everything that needs attachment currently bolts through welded-on tabs). That would change when I rivet the side panels on on the underside of the frame of course, but I'd like to use as few as possible for the aforementioned reason.
I know there are no right-or-wrong answers, but there are extraordinarily knowledgeable people here whose opinions I value greatly!
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