Body fasteners ...

[LateApex]

This is a simple question ... maybe.

What kind of fasteners are you using to lock the body down on final install, and where are you placing them?

Several fasteners are pretty straight forward. Button head screws on the rear panel and 1/8" rivets on various pieces of sheet aluminum that decorate the wheel wells. But where is the heavy lifting done? Along the door sill I presume. The front door pillar may take one fastener depending on how square the fiberglass is, noting the "1/4" gap suggested in the assembly manual. Aside from interference fit with bulb seal all around, and the rear panel fasteners, body attachment opportunities are somewhat limited methinks.

What are you doing or planning?

Much obliged :-)

[David Williamson]

I did mine following the instructions. The back mounts, door sills, and the pontoons and it is solid. At speed the hood does move a little at the cowl but no issues
David W

[edwardb]

The body is held in place in multiple ways. Two most significant are probably the rear body mounts to the frame and how it rests squarely on the door sills. The manual shows using self-tapping screws through the body into the frame door sills. I used 1/4" nutserts and 1/4" flathead bolds. Covered by carpet that I wrapped over the edge. Additional things that contribute: Screws into the door pillars (although I agree if your best alignment isn't against the pillars, doesn't do much good), rests on the firewall and firewall extensions along the ends and sides, pontoons with splash guards, rear splashguards including the attachment to the body at the rear corner, and finally the hood firmly latched over the front of the body. It all adds up to being very solid. I've never noticed any hood shake with mine. And I've had it faster than I've told my wife. :rolleyes:

[J R Jones]

The body is held in place in multiple ways. Two most significant are probably the rear body mounts to the frame and how it rests squarely on the door sills. The manual shows using self-tapping screws through the body into the frame door sills. I used 1/4" nutserts and 1/4" flathead bolds. Covered by carpet that I wrapped over the edge. Additional things that contribute: Screws into the door pillars (although I agree if your best alignment isn't against the pillars, doesn't do much good), rests on the firewall and firewall extensions along the ends and sides, pontoons with splash guards, rear splashguards including the attachment to the body at the rear corner, and finally the hood firmly latched over the front of the body. It all adds up to being very solid. I've never noticed any hood shake with mine. And I've had it faster than I've told my wife. :rolleyes:

Spot-on Paul.
Not being a "Coupe" guy I am not familiar with the manual recommendations, and I am shocked at the mention of self tapping screws. This could be bad IMO. The SAE and maybe DOT require grade five fasteners on automotive structure or operating systems. The heads are marked with three bars. Sheet metal screws are not appropriate.
Thread cutting grade five fasteners are much better but require precise pilot holes and specified torque.
https://www.fastenersclearinghouse.com/fastener-search=self-tapping-thread-cutting-screws&material-type=grade-5&Cat1=PRM7DED642D2914;&Cat2=FL3961BCE05611;&Cat3=FL9CE859C71821;

If I use 1/4 in./M6 fasteners, they are numerous and in a discrete pattern. I use 5/16 in./M8 flange heads for wider spacing. Critical fasteners are more effective in shear than in tension.
jim

[LateApex]

The body is held in place in multiple ways. Two most significant are probably the rear body mounts to the frame and how it rests squarely on the door sills. The manual shows using self-tapping screws through the body into the frame door sills. I used 1/4" nutserts and 1/4" flathead bolds. Covered by carpet that I wrapped over the edge. Additional things that contribute: Screws into the door pillars (although I agree if your best alignment isn't against the pillars, doesn't do much good), rests on the firewall and firewall extensions along the ends and sides, pontoons with splash guards, rear splashguards including the attachment to the body at the rear corner, and finally the hood firmly latched over the front of the body. It all adds up to being very solid. I've never noticed any hood shake with mine. And I've had it faster than I've told my wife. :rolleyes:

I am leaning to the larger gauge options like 1/4" bolts. Paul, may I ask how many you placed along the door sills? I may tap directly into the frame instead of the nutserts ....

Thx for your response!

[LateApex]

Jim, what do you mean by a "discrete pattern"?

[edwardb]

I am leaning to the larger gauge options like 1/4" bolts. Paul, may I ask how many you placed along the door sills? I may tap directly into the frame instead of the nutserts ....

Thx for your response!

Three. I though about tapping the threads in the frame. Would probably be OK. But wouldn't be a lot of threads. I decided to do nutserts for the added security. Visible in this post from my build thread. (Scroll down)

https://thefactoryfiveforum.com/showthread.php?26630-Edwardb%92s-Gen-3-Type-65-Coyote-Coupe-59-Build-Complete-and-Graduated&p=361618&viewfull=1#post361618

[J R Jones]

Jim, what do you mean by a "discrete pattern"?

LA, IMO again, Honda, Yamaha and Toyota are masterful in the use of fasteners. Thier examples are worth noting. As a side, between the two, metric and SAE, I prefer metric.

With structural heavy parts, the fastening is more simple. With one or more light or flexible parts, fastening becomes more demanding. Consider the fasteners in an aircraft, small and numerous.
Smaller fasteners benefit from patterns like rivets. Two rows, staggered in sequence. http://www.tpub.com/air/13-25.htm

When the fastener is stronger than the material fastened, you want the clamping spread-out lest the material flex or yield under load. Fiberglas and aluminum sheet require careful fastening, and plastics have the additional issue of material creep. The material presses out under the fastener head and the fastener looses clamp load. More smaller fasteners are better.

In my vehicle projects I will bond aluminum tubes and blocks to FRP for critical fastening when fastening space is limited. An example is hood hinges to fiberglass hoods. The blocks are threaded and the tubes have Rivnuts so that ultimately the fastener loads are distributed to the fiberglass part over several square inches. Support plates positioned under fastener heads like washers is also a solution.
jim