NOHOME wrote:
Wisdon is gained through experience. Experience is gained through a lack of wisdom.
Real smart people told Mr Chapman that a all fiberglass coupe would never work. While it might be a correct statment, he went and did it anyways. Once. Was not a wise thing to do. Dude still did ok with his life.
Draw the thing up. I would do it out of flat sections welded together. Tig welders are not very expensive and will serve you for the rest of your life, so a good nvestment.
Once you draw this thing out, have someone water jet cut the parts. Once again, not that expensive for the results you get. Water jets are not the oddity they were five years ago and prices are down due to lack of work in manufacturing.
Buy a good set of dimple dies; you are going to want a few access holes and these look good and keep some rigidity in the panel.
Panel adhesive where you don't want to weld.
Never heard of heat treating aluminum after welding. Have had to preheat to get the stuff to weld, but not heat stress relief like with chrome molly and DOM mild steel. Would love to learn more about that.
Sorry, but I would not MIG anything aluminum if it were structural. Just me but I dont see the penetration like with TIG. Not saying it wont work, just that I have no experience with it.
So start drawing and post up so we can see what you are thinking.
Pete
Re-heat treating aluminum is not the same as stress relieving steel post weld. With out heat treatment even fancy alloys of aluminum are pretty damn weak for a structural member. When you weld the aluminum you kill the prior heat treatment, and wind up with severely weakened spots around the welds.
I agree he shouldn't be discouraged by the nay sayers...
But he shouldn't start dumping money into water jetting and barrels of industrial adhesives when he doesn't doesn't understand what he is up against. Colin didn't just run with some crazy idea simply because they told him not too, he did it because his experience and knowledge told him he could. Very different things.
YaNi wrote:
Check out this aluminum monocoque build by a University from Oz.
Trev Part 1
Trev Part 2
Basically an aluminum honeycomb monocoque bonded together with epoxy. I doesn't take too long to draw it up in Solidworks and have it run some basic FEA on the the suspension points. I have a vision for a road going 3 wheeler with a 600/750cc sport bike engine instead of the dinky electric motor. The thing weighs less than 600lbs so 100+hp would be wild.
Very cool, but I don't know that it proves much. They show no numbers for torsional rigidity, and have no info on how well it holds up to miles of rattles.
Its just a bunch of engineering students at school trying something, that doesn't mean it works well, or better then standard methods.
I can go to school, open our lab and start gluing together compressed saw dust talking about how it forms a composite material with the resin and going on about the strength of a single cellulose fiber of spruce....
They aren't really making a race car, they are making a super mileage cruiser, so what is good stiffness for them may not be good for corner carving either.
It seems like making an aluminum frame for the sake of making an aluminum frame. If you just want to do something different, I guess go ahead... but if you want something that works well at least START OFF with what has been proven, building any car is a major undertaking and there is time to try other ideas on future iterations.
