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madman
04-21-2006, 05:21 PM
I designed a new drink holder from aluminumn. I need to make 90 degree bends in .125 thick 50 series aluminumn. What type of small cheap metal brake would do this nicely. Any tips or hints would be much appreciated. Thanx

dicks42000
04-21-2006, 05:42 PM
Madman;
First question....How wide is the piece to be bent ? That usually affects the "tonnage" or capacity of the brake. If it's a relatively narrow piece as I suspect, any box & pan brake, straight leaf brake or on of the chi-com 3 in 1 machines would probably work....
A press brake (eg. a 3 in 1) will usually only make a bend up to 90 degrees.
Investigate the bendability of the Al. alloy that you want to use too.
Hope that helps.

Evan
04-21-2006, 05:44 PM
A drink holder from 1/8" aluminum? Buy "O" condition dead soft alloy and you can bend it like cheese. Bending will work harden it but you won't have to worry about the radius. If you can get it soft then any sort of brake will do.

Ries
04-21-2006, 06:50 PM
The cheapo chinese stuff wont do this- for instance, the 3 in 1 machines are rated for 20 ga, which really means 22 ga. 1/8" aluminum is a lot thicker and harder than that.

Most 16ga brakes, especially cheap chinese ones, will get sprung on 1/8" aluminum, especially if it is very wide. People think that just because aluminum is softer, you can use thicker material than the brake is rated for. Not true- 1/8" is 1/8".

Width of the finished part is a factor- you might get away for a while with bending 3" wide material on a 4' brake, although many cheap ones wont clamp material that thick.

But if its very wide, you want a heavier brake. Chicago makes nice 4' and up finger brakes in 12 ga and 14 ga capacity that will bend this stuff for the next 50 years without blinking.
http://www.dreis-krump.com/hand_brakes.htm

You can buy little press brake units for a hydraulic press, from Northern Sales and the like, but they usually arent designed properly- the dies are usually sized for 16 ga or so, even though they pretend they will bend 1/4" plate.
With aluminum, especially 6061, its important to use a big enough radius for the thickness, otherwise you will get cracks at the bend.
If you look at this page-
http://www.dreis-krump.com/Dies.htm
you will see that even in steel, a 90 degree in 1/8" material should use a 1" wide V in the lower die. Many of the small manual "press brakes" are sold with much smaller v dies than this.

If you must go the cheapo route, buy some of the chinese crap from Grizzly, break it, and get crummy bends, then you will want to step up to a real tool. But most of it is rated 20 ga, even the heaviest is only rated 16g.
http://www.grizzly.com/products/category.aspx?key=520010

The little bantam press brakes are very nice-
http://www.vansantent.com/sheet_metal_machines/pneumatic_press_brakes.htm

Evan
04-21-2006, 06:58 PM
People think that just because aluminum is softer, you can use thicker material than the brake is rated for. Not true- 1/8" is 1/8".

Trust me, O condition 5005 alloy aluminum can be bent on a brake made of balsa wood. It only has around 6000 psi yield strength. You could easily bend 1/8" with your fingers. Once bent it will harden up, some right away like copper and some with aging.

IOWOLF
04-21-2006, 07:06 PM
for something say 5 " wide how about a Hyd. press with 2 1" dia.rods 5 or 6" long welded to a plate an inch or so apart parallel to each other on the bottom and a vertical plate in the ram for the "blade". simple but useful.

Evan
04-21-2006, 07:46 PM
One again, if you use O condition 5005 you won't need to worry about a radius. It can be bent sharp. 5005 O or even H12 condition can be bent at a radius of 1/2 - 1 of thickness. 5005 is a strain hardening alloy and develops strength by work hardening.

Mike Burdick
04-21-2006, 08:05 PM
madman,

Inexpensive you say...

If the object to be bent is small enough one can use the ordinary bench vise. Just make some dies for bending the shape you want and fit them so they can be quickly placed over the jaws.

speedsport
04-23-2006, 09:40 AM
The person asks a simple question. Why did that have to morph into a "Cheap Chinese piece of crap" rant?, GET OVER IT!, damm dude if you don't like their stuff don't buy it!, or do you think everyone is entitled to your opinion?. I get sick of hearing that crap.

Ries
04-23-2006, 10:20 AM
That wasnt my "cheap chinese piece of crap" rant- but I suppose I could give you one if you want.
Actually, I have the bad reputation on several forums of saying that some Taiwan equipment, particularly Jet brand, is actually decent.
For that crime, the real "anti-chi-com" crowd thinks I am Judas personified.

He asked if a three in one machine would bend 1/8" aluminum. I gave him my OPINION, which is that it would not.
This forum is ALL OPINIONS- thats all it is, and if you dont want to hear peoples opinions, what the heck are you doing reading any of this at all?

I am of the "OPINION' that most of the very inexpensive chinese sheet metal equipment is not very high quality, and will usually not even bend its rated thickness of material, much less TWICE its rated thickness.

I am of the "OPINION" that Chicago D&K brakes will do this job, and are very high quality.

You dont like those opinions, tough titties.

As far as 5003 in O hardness goes- yeah, it will bend easily. But how available is it, how does it compare pricewise, and how will it take to actual usuage once it is a finished product?
I made the assumption, (my bad) that he probably would be using 6061 T6, mainly because about 90% of all easily available aluminum is that stuff.
So I gave my crummy opinion of what would work to do that.

Where I live, soft aluminum alloys are special order, in several hundred dollar minimums, and so I make do with 6160, plus I know it will weld and anodize in a predictable manner.

GKman
04-23-2006, 10:43 AM
I'm usually stuck with 6061 T-6 (harder than the hubs of hell) or mystery metal from the scrapyard so I temper it before bending. With an oxyacetelene torch adjusted too rich, smoke up thesurface of the metal (just the bend area if you want to). Readjust the torch for neutral flame and burn the soot off the workpiece. Let it air cool and it will be soft.

Also aluminum bends better perpendicular to the long grains that are formed when rolling to thickness. Therefore bend perpendicular to the lettering on the sheet.

dicks42000
04-23-2006, 11:19 AM
Well said Ries. I never suspected that it would go off topic that much. Who cares anyway. I have a green 40 in. 3 in 1 at home, and have bent 1 1/4 x .125 wide pieces of dead soft Al. to 90 with little trouble (but was probably pushing it). It was mystery metal from the bin, but I did torch-anneal it. Worked for heat sinks though. As said before, 3 in 1's work, may not be the best stuff & not a production machine, but they are affordable.
My Chicago box & pan brake has an otional wide finger with a radius on it & set back to allow bending of thicker stock....
My opinions & experience, anyway.
If you need power & production, Duncan Iron Works on Vancouver Island makes a hydraulic shear & brake that'll do up to 1/4 in. steel plate. Nice idea, but custom orders only.

Paul Alciatore
04-23-2006, 12:54 PM
I have one of the 3 In 1 machines and love it. Is it cheap? Yes. Is it Chinese? Yes. Will it bend 1/8" thick aluminum in any alloy. Not if you want a 90 degree bend. I can get away with bending 0.040" aluminum but I have to "assist" the bend with a hammer and block of wood to get the final 5 or 10 degrees for a 90 degree bend.

The dies on these machines are made for specific thicknesses of material. It is true that they will operate over a range, but 0.125" is way out of that intended range. It would probably bend a piece that is 1/4" wide or less, but even then, the results will leave something to be desired. I don't have any experience with the 5005 that Evan mentions so do try it. But it sounds a bit soft for my uses.

I do bend 1/8" panels occasionally (standard rack panels) and I have a 6" bench vise with aluminum jaw inserts for that. I use a block of oak and a 2 pound hammer to make a nice 90 degree bend in panels up to 5 or 6 inches wide. Beyond that you probably will need a costly brake to make nice looking bends in material that thick. As others have said above, it is tonnage.

Paul A.

madman
04-23-2006, 03:30 PM
Now Now lets not get testy guys. I appreciate the ideas. I am using 50 series aluminumn for my product. The 6061 just cracks breaks fractures you get the idea. The 50 series worked well. i laser cut the shapes and bent them up. Look cool and i gave some away but i wanna sell them to make some hobby money. $11.oo bucks with two stainless steel bolts or they just fasten automatically on the sides of kennedy toolboxes and dont require any holes or adhesives at all. Thanx

Evan
04-23-2006, 05:01 PM
The brakes I am familiar with have an adjustment for thickness and clamping pressure. My comments were based specifically on the fact that Mike said he would be using 50 series aluminum and that he was making a drink holder. That means it doesn't have to be strong, it isn't going to be big, it isn't likely to be welded (5005 welds just fine) and there are no other particular concerns such as apply to other alloys and tempers. Mike's question was quite specific and so were my answers. They were not meant as general comments on bending aluminum. I have experience with all the alloy series of aluminum and have bent, beat, rolled, sheared, welded, drilled, riveted, heat treated and machined them.

gundog
04-23-2006, 07:36 PM
Here is a option for you buy one of these or make one and use a shop press. I am unclear of the angle or shape you are bending. I bend 90* in .250" 5052 Al for a small business I started the bend is 12" long and It has to have a 3/8 rad. or it will fracture at the bend. There are also variations in material when I first started I was using a 1/4" rad. and all was good a new batch of material and they all fractured using the same dies. I built a H press and made my own dies to make my project. Do a search for my home shop press.
GD

http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_21896_21896

Here is the link to my project. I have updated the controls to electric with limit switches I will make a new post showing the new controls soon as I get the time.
http://www.homeshopmachinist.net/bbs/showthread.php?t=15517&highlight=press

Scishopguy
04-23-2006, 07:55 PM
GKman,

You don't have to use an O/A torch to aneal the T-6 aluminum. It only takes 3-4 hundred degrees to draw the hardness out of it. I use a bernzomatic torch and it works fine. on 6061. If you get into other alloys it is a different ballgame (especially 2024). Anyway, not trying to hyjack the thread.

Jim (KB4IVH)

darryl
04-23-2006, 09:58 PM
Is this going to be a trick drink holder? Will it refill itself? Can beer be used as cutting fluid? Hey, if you're going to be coming up with a produce, ya gotta consider all the angles. / :)

speedsport
04-25-2006, 11:05 PM
I bet everyone on this board has heard what is said about opinions. And most of them stink.

madman
04-26-2006, 11:25 AM
Wow lots of great ideas and tips. Thanks to everyone. I went to the local metal fab shop. The guy looks at me funny when i pull out like a box full of these beautiful laser cut flat things with a hole in em. I ask him can you bend these up for me ill pay cash money, His eyes popped open i swear i heard a ka-ching in his head go off ha ha. Bottom line the bends i desired he couldnt make due to the throat depth required .Of course requiring a new shoe to be made. I took down some dimensions traced on a paper bag of course (the home shop machinists friend) and went home. I made a new shoe now lots of milling and am ready to return with it to try again. I was just kinda surprised a little not a lot though that once again one of my hairbrained schemes to put a couple of nice drink holders into peoples fishing boats ran into such a pile of extra work. I thought a fab shop would have the capability to bend simple things. I also went to another more modern shop and the guy (a friend) actually bent up a pile but it was maxing out the capacity of his shoe. He hurt his shoulder playing baseball so now its back to the other shop and the new shoe design. Thanx to everyone for all your input. If i knew more bout computers id post a pile of photoes but ive kinda given up on 1. EBay after getting ripped off 2. Paypal never could get it to work spent hours screwing around with that site 3. Photobucket i just am too stupid. Computers and i need some quiet time in a college enviroment to work properly and i just dont have the time or patience for them. thanx again Mike