laminated cross member( so to speak )

[5-90]

Given access, a bucked rivet will be better (since it's solid.) Problem with the original idea I posited is that you don't have access to both sides of the rivet - unless you're going to smash the panel flat - which defeats the purpose of using the wriggly tin (and the entire idea has been scrapped anyhow.)

However - what's the largest grip you can get on a bucked rivet - can you make an inch and a half or so? I know you'll want to have it go through something solid, and both heads need to buck up against something to gain some compression - but I'm playing with an idea again, and I'm looking for information.

Also, what would be the advantage to a hot-bucked rivet vice a cold-bucked rivet in this application, or do you know offhand? Just wondering how big a factor work-hardening will be...

I don't know if you saw it, but take a look at the other thread I started and see what you think. The principal problem here with a lightweight laminate is that you have to use a strength member that won't lose column strength with impact, can be worked in a basic shop, and allows access for finishing BEFORE assembly, so it won't rust from within once you get the thing wet...

5-90

 

[Weasel]

read what I posted about rivets, your loading them in the wrong direction!!!!! Not real smart.

And bead blasting won't really help with mild steel as the welds don't really get brittle.

Unless you are doing LAYERS of DIFFERENT materials it would be a waste of time. Steel doesn't benifit at all from running multiple layers vs. one solid peice. It's homogenous, no graing to it, same strength in all directions.

 

[JeffV]

MaXJohnson & Weasel are "spot on" with their analysis.

Lamination of light materials via welds or rivits does not in itself provide additional strength. Without vertical structural support, either gussets or other cold forming process, light weight material is impractical.

Because you are starting with flat material, the amount of welding required will create uncontrolable twisting and warping. On a piece the size of a cross member, warping will definitely cause problems with installation, and likely create preload stresses on mounting hardware.

Light weight & strong? Think about something similar to how aircraft wings are structured. 2 opposing large radiuses with internal vertical gussets in both X & Y axis.

To make this work, precision & tooling would be an issue. It could be done in a "basic" sheetmetal shop i.e. shear, pressbrake, roller, welder. Unconventional manufacturing sequence would help. The ends of the assembly could be flattened and formed, punched or drilled, after the internal structure is in place.

 

[Mr.OverKill]

the reason for doing this in the first place is to " make a thin, flat, smooth and strong cross member/ belly pan skid plate combination, all on your own"

unless i am mistaken ( whitch i am not, because i read through ) i never mentioned weight as an issue, he11 i am running a chevy 350 with more power than i know what to do with and dont care how heavy my junk is, i want steel plateing every where it wont block the air flow for my radiator, think tank then you will understand slick/ smooth and strong along the belly without spending too much money on stuff i can build in my garage ( i have "some" cool tools) instead of buying other peoples designed stuff, dont get me wrong, their designes are awsome and i would love to have some of those designes on my junk but why pay for something i can build for half the cost ( or less)

i feel some got too in to the aerospace designing "strength to weight ratio" i like the ideas i have heard and if i build a race XJ and i need to keep it light i will be all over the kevlar and carbon fiber laminantes with the aluminum honey comb core like the horiz stabs and access panels of the top fighter AC of our time ie. the F14, F/A 18, A,B,C,D,E & F models as well as the F/22 raptor or the JSF. ECT...ECt... i know how to do light and strong a need to figure out how to do strong and ridgid without the bulk and keep it slick.

well i am babbeling so i am outa here

peaceeace:

 

[Weasel]

think tank

that5s a good way to go but even if you do a flat 1/2" plate of steel, your gonna need some kind of shape to it or it will bend.

 

[cruzmyxj]

think tank then you will understand slick/ smooth and strong along the belly without spending too much money on stuff i can build in my garage ( i have "some" cool tools)

Well I am also in the Army National Guard and um, tanks are made out of depleated uranium. You would need some even cooler tools to work that. That being said, I think I would go with a conventional desighn. Gusseted, and cold rolled steel. Roll lips, gusset for strenght. Yea, it's a basic design, because it works.