Bending 1/8" Aluminum Plate vs 304 SS

I want to make a panel to mount some regulators and valves. I planned on using 6061 Aluminum which was 36" long and 18" wide , 1/8" thick
and putting a 90* bend so I have 2 aproximately 8" legs (exact leg dimension is not critical). I have a price for $84 including some internal holes from a vender. But I am concerned about bending this 1/8" plate using my finger brake. I have read that AL needs heated first. I would then also need to get it Black anodized. So this all ads up. The cost for a SS 304 plate is 110 but still needs bent but no finish is needed. Can I bend this in a tabletop 4' brake? The bottom leg is only for mounting and a stable base. I am looking for some ideas on the most cost effective and easy approach to complete this little project. I need 1/8 material.
Thanks in advance.
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Neither would be my first choice considering the operations you have planned. 304 is hard to bend without cracking although a 90 degree bend is probably possible. 303 is a better choice. I would definitely go with the stainless and avoid the anodizing. If your break can't handle the thickness then I would just bend it with some clamps over the edge of the bench.
starbolin
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snipped-for-privacy@sbcglobal.net says...

Are you sure you're not confusing 303 and 304? 304SS bends very nicely. I've never seen 303 sheet - it may be available, but not commonly.
Ned Simmons
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snipped-for-privacy@comcast.net says...

If you have access to a mill, you can try what I did to make this box.
http://www.suscom-maine.net/~nsimmons/news/Mailbox00.JPG
http://www.suscom-maine.net/~nsimmons/news/Mailbox01.JPG
http://www.suscom-maine.net/~nsimmons/news/Mailbox02.JPG
The cuts are v-shaped and were made with a 90 degree uniflute (Ford type) countersink, about halfway thru the stock. Make sure you add a little extra width in the cut to account for springback.
Like this...\_/ instead of this...\/
It's best to experiment first on a piece of scrap. Once the cuts are made it's very easy to make a nice accurate bend. Depending on the bend direction relative to the sheet's grain, 6061 may show some small surface cracks on the outside of the bend, as visible in the second pic. As you mentioned, annealing should eliminate this.
I've never tried this on SS, and imagine it'd be a bitch. If you want SS, get a fabricator to do it.
Ned Simmons
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You have to derate your brake by 2 gages for stainless. So if you have a cheapo "16 gage" finger brake, then you can only bend 18 gage stainless with it.
Stainless is hard stuff, and requires big tools. And you sure as heck arent going to be bending it on the edge of the table with clamps, unless it 24 gage or something really thin like that.
1/8" stainless takes a BIG brake. I can bend short pieces of 1/8" stainless in my Chicago D&K 12 gage finger brake, which weighs over 2000lbs, but it doesnt like it, and would risk popping the brake to bend a 3 foot piece of it.
A 30 to 50 ton press brake is what they use in industry to bend 1/8" stainless.
I dont see why you need to heat the aluminum before bending it- you just need to make sure you are bending it at a big enough radius not to crack. You might need to make a round nose bar for your brake- just a piece of 1/2" round, welded to a piece of flat bar, then clamped in place of your fingers, and you get a nice radius bend.
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Ries wrote:

Another way is to put a piece of aluminum the thickness of the radius bend it. Put that bent piece on top of the good piece and tight against the fingers when you bend it and you get the radius formed in the good piece. Save that scrap bent piece for the next aluminum bending job.
Another way is to make a partial bend, release the clamp and push the metal in a little and finish the bend.
John

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Unless you put a very large radius bend on the 1/8th aluminum it is likely to crack. To prevent this the trick is to soot up the bend line with an acetylene flame. Adjust to a neutral flame and burn off the soot. This will remove the heat treatment making the aluminum much easier to bend. My vote is to go for stainless and just have the two bends done commercially on a press brake. The delivery time will be fast since most shops that cut stainless form stainless. Anodizing will require a separate vendor. Randy
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I need 1/8 material.

Since the stainless is stiffer than the aluminum, are you sure you need 1/8 stainless. Pick thinner stainless. You will be able to bend it ( assuming you can bend the aluminum ). And it will cost less than 1/8 stainless.
Dan
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gtslabs wrote:

You want to use 3003 or 5052. I have bent small pieces of 2024 and 6061 by marking them with ivory soap and heating along the bend line with a propane torch until the soap mark turns brown. I then quench hard in water. This will make it quite soft for an inch or so each side of your heated/quenched area.
I bend a 3.3" wide piece of 1/8" 3003 or 5052 on a small Chicago finger brake, and it works quite well. I put a sharp, 90 degree bend in it. I think you could bend an 8" wide section of 3003 or 5052 without damaging your brake. 2024 and 6061 will likely crack without annealing, and might overstress the brake, too, before they give.
I have serious doubts you'd want to bend 1/8" SS 8" wide in any small hand brake. That is getting into the range of a press brake. You could do it with one of those massive 8 - 10' brakes with the counterweights that are as big as bowling balls, but only Arnold Schwartzenegger could do it on the typical 4' brake.
I might mention that my little 3' Chicago brake has to weigh over 400 Lbs.
Jon
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