Aluminum body panels...looking for REAL info

[Weasel]

Apartently 5052 is hard to find and not cheap. 3003 is cheaper and not that much weaker. Also when you get into the 5052H36 your going to have a brittle piece of metal, not something you want for a door skin.

Based on what you want I would look into 3003 H-16 series.

And 6061 T6-T651 is not the strongest alloy aviable.

 

[Flowers]

i am....but some of the aluminum will be used for ground effects and a huge ass air spoiler for the back......

I did the math. If you locate the spoiler just behind the rear window of the chop, it will only affect your anti-squat by 10%. Although, the spoiler cannot be "huge ass" it must be < 5 sq. ft.

Hope this helps,

Flowers

 

[Beezil]

eagle, I'll be exposing that panel to tension the first five minutes i get on trail....

not so much as a concern as flying shopping carts though...gotta protect the poseur rocket.

weasel, thanks for the reply...

the specs on 3003 looks kinda pathetic though....

tensil 26.0 yield 25,000lbs/sq/in elongation 5 (%-2" in .062) and a brinell hardness of only 40........

the price ballparks close to similar, availability isn't a concern, i can get pretty much any material I want from a number of vendors.....

I wish I could sample some drop-off........

what do you think, i'd love to hear it!

 

[Rev Den]

I wish I could sample some drop-off........

what do you think, i'd love to hear it! [/B]

I think that is your BEST idea...get a couple sq ft of each, and beat the hell outta it for a while...see what works. It may be low tech, and I do not have your knowledge, but that is where I would start. Also...you may have thought of this...but ask at some of the Race car shops in the area.

Rev

BTW For ground effects I would recommend a more flexable material to handle the potholes of the city streets.

 

[Weasel]

3003 has a yeild of 21ksi at H14 which is 7ksi less then the 5052 H32. But it is much more formable and fatique reistant then 5052. It's probably going to come down to price and avalablity now. Carroll Smith state he only would use the 5052 in the H32 form, I'm assuming because of the brittle issue with higher treatments. My chart lists 3003 as having an Ultimate tensile strength at max heat treat of 30ksi and a minmum tensile stregth annealed of 16ksi. 5052 is 39 ksi and 28 ksi for the same cat. Another alloy I see listed that may work is 3004. Rated at 41 ksi and 26 ksi for the same cats above. The only thing is I don't have any information on how it well it forms.

6061-T6 may also be an option and it's properties are quite a bit better then either 3003 or 5052 it's just a bit harder to from.

The reason I'm not jumping allover the 5052 is because I'm pulling my information from Carroll Smith's book Engineer to Win and he doesn't seem to talk alot about it. Except he would use 3003 instead of 5052 and he use 6061-T6 because it's the strongest alloy he says that can be bent over a block with a sandbag and hammer.

You may want to check into 4130 sheets or similar. You would have to run the same thickness (maybe .035 or even .025) and still come out ahead on the strength issues with out much weight.

 

[Beezil]

thanks, that's great info.....

I'm wondering if carroll smith encountered availabilty problems with 5052 as a reason he omits any info on the alloy in his book

I will be giving 3003 a good look....

I know this might seem like a needless thread for most, but for me personally its something I don't know about, and learning something new is fun, so eat me you people

 

[Weasel]

thats what I was thinking...to hard to get and probably to expensive (5052)

 

[rixXJphx]

Just a couple of thoughts:

1. The weight savings of aluminum vs. steel were based on equal thicknesses.
For equal strength, rather than 0.060 steel (~16 ga), a thinner steel (~ 20 or 22 ga) would work. Therefore, the weight savings-to-strength ratio would result in a savings of about a 44 lbs instead of 88.
Sorry, I haven't run the numbers; and, it would depend on which steel was used (33 ksi and 50 ksi being the most available).

2. Though the panels are short, there's a possibility of temperature deflection, winter-to-summer, when aluminum sheet is secured to a steel frame.

 

[Beezil]

20 or 22 ga) would work

hey guy, thanks for the reply, i appreciate it....

I want you to know that so what i am about to say doesn't come across like I'm a fat jerk or anything....

I am a metal manufacturer by trade, but the limit of my experience ends with steel.....

at the moment, I probably have on hand thirty or fourty TONS worth of steel, some of it is 20 and a little of it is 22 gauge. I have first hand experience working with it, which I believe qualifies me to ask this question:

are you freakin nuts?

20 gauge?

22 gauge?!!!!!!!!!!!

I know you are probaby not clairvoyant, so you probably don't have a good idea what it is I'm doing, but both those gauges are barely enough protection against twigs! I could take a screw driver and punch a hole right through 22 ga crs! how could you come up with a suggestion like that for my application? YIKES!

 

[4ward]

Yeah, this thread is pointless in a jeep needs way. It's good tech as far as material strengths.

I don't understand why you're worried about the strength of it. Unless you're going to run .25" thick it's going to be punched, bent, and mutilated no matter what. I'd find the cheapest and easiest to bend and go with it. That way it doesn't crack and break when you go to beat it back into shape. Have you looked to see what the JP aluminum bodies are made of. They are easily worked back into shape and seem to hold up decently.

 

[Eagle]

... at the moment, I probably have on hand thirty or fourty TONS worth of steel, some of it is 20 and a little of it is 22 gauge. I have first hand experience working with it, which I believe qualifies me to ask this question:

are you freakin nuts?

20 gauge?

22 gauge?!!!!!!!!!!!

I know you are probaby not clairvoyant, so you probably don't have a good idea what it is I'm doing, but both those gauges are barely enough protection against twigs! I could take a screw driver and punch a hole right through 22 ga crs! how could you come up with a suggestion like that for my application? YIKES!

I don't claim to have any idea what you plan to do with this. What you SAID you were going to do with it is skin a door. Boor skins are generally 20 gauge or 22 gauge steel. Now, if you're really talking about making this into a stressed skin panel, you should say so. If you're concerned about penetration protection (just what are the brothers carrying in your 'hood these days, anyway?), call up a local armored car company or limousine company and ask what they use to ward off RPGs.

Sorry ... I'm honestly not trying to be a wise-a$$ here, but for a stinkin' door skin I just don't understand all the concern about tensile strength and such. Door skins are skins, that's all they are. They are generally not structural. Why is yours otherwise?

 

[Eagle]

BTW --

One thing to remember about most tempers of aluminum is that they work harden almost immediately. One bend is usually all you get. Try to bend it back and it breaks.

 

[4ward]

Can't find anything about the jp bodies other than they are made of marine grade. So, I believe that was covered on the first page of this oh so informative thread.

The comp and hardcore guys are having good success in getting their rigs looking good again with some hammer and dolly work. I'd investigate this farther.

 

[Beezil]

this is going across the lower portion of the door openings on formed steel tubular ribs

here, I'm quoting myself.....

I know its not a very complete picture, i should have been more clear......"door openings on a tubular frame"

openings...........means no doors......I didn't remove them myself....a tree did it....

so I'm building a tubular-reinforced side panel to protect my ass in a lay-over is essentially what I'm up to.

 

[Beezil]

"marine grade" comes up in the description of both the 5000 and 3000 series, actually, the 5052 which is what I wanted to go with, but it also comes up as a description of that weez was suggesting with the 3003 (thanks again weez)

Yeah, Weasel, it'll probably will come down to price point.....I'll hafta ask "what would you pick" questions with a couple of my vendors.....

 

[Lincoln]

You guys get this figured out. I still want to replace my cross member and skid with aluminum.

You might also check out the anti corosive (can't spell) properties. I think that is where the "marine grade" label comes in. There are several boat mfg's around here that use some different grade. I don't know what it is, but salt from the roads with discolor and pit the heck out of it.

You don't want to have to polish it after every trip to the mall.

Later,
Lincoln

 

[rixXJphx]

are you freakin nuts?

20 gauge? 22 gauge?!!!!!!!!!!!

.... so you probably don't have a good idea what it is I'm doing, but both those gauges are barely enough protection against twigs!

No offense taken.
Nuts is nice sometimes, that's when the best ideas flow!

Seriously, I agree that your-originally indicated 0.060 inch (~16 ga) steel IS more appropriate to your armor needs. I wasn't aware of how much penetration resistance you desired.
I've used 16 gage steel roof deck for rifle ranges (in addition to internal armored baffles). Tests proved 1) a .223 would penetrate the 16 gage steel 2) the bullet lost so much energy that its descent was *nearly* harmless.

However, the main point of my original post remains:
That for comparable strength performance (whether as a skin or as penetration resistance), aluminum MUST be thicker than steel.
Therefore, the comparison should be 0.060 steel (47 lbs) vs. ~ 0.090 aluminum (24 lbs).
The weight savings isn't the original (47-16=) 31 lbs that you calculated, but rather about 21 lbs.
Agreed, that's 21 lbs saved (or placed elsewhere on the rig).

Best wishes on the rig.
-Rick

 

[Weasel]

Any of the 3003, 5052, 6061 series are all excellent in corrosion reistance so that should not be a problem.

Somone already mentioned it but I am going to start looking into ways to get some alum or composite skids.

 

[rixXJphx]

Pound for pound, laminates are the strongest sheet materials.

If ya took a LOT of aluminum license plates and kind of overlapped them in layers with some epoxy and pop-rivets.....

 

[Beezil]

one ton,

not only did I draw it, but today I'll need to program a few lines of code for the cnc tubing roller!