Is bending aluminum really that hard?

ckrtech · Post by **ckrtech** » Sat Dec 20, 2008 3:32 am

So far, all of the hiccups on this project have been solved easily. Do some quick research, double check a few things, maybe post a message here, and then continue.

Tonight I attempted to start bending the aluminum wall for the case. I cannot explain the pain this has caused. I have various sets of pliers, but the job just takes all sorts of energy only to yield something unprofessional.

Take a coat hanger. Undo the wrapping just below the hook, unbend it, and now try to bend it back exactly to the way it was. Does it look like all your other hangers? Probably not. I've warped the aluminum every which way while trying to bend it, and I feel I am in danger of scrapping the project if this doesn't work. That's quite a shame considering the total time and money spent.

At the moment, about 2 1/2 of the 4 walls are done. I put a flat box (computer motherboard box) full of various heavy parts on top of the front plate and wall as the epoxy continues to cure. I put an old UPS battery backup on top of the box. That's a good amount of weight. I hope it helps magically flatten out the front plate. While it didn't warp *that* much, the case may end up bordering on ghetto.

I feel like I am stuck on a train I have to ride until the end of the line, but I dread making the last few bends, cutting off the extra piece somehow without disturbing the thing as a whole, and finishing up the sidewall.

Anyone have any pointers? It's 3:30 a.m. I am headed to bed.

jjhammerstein · Post by **jjhammerstein** » Sat Dec 20, 2008 7:37 am

I assume you're doing the edges in aluminum, and this is what you're bending.
The best way I've seen is this:

Make a wooden mold that has the same outer contours as what you're putting the edges on.

Clamp your aluminum strip to it.
Bend it to form the mold.

Take it off of the mold.
It should be perfect for your edges now.

ckrtech · Post by **ckrtech** » Sat Dec 20, 2008 2:13 pm

That sounds like it would make things easier. Unfortunately, I do not have the resources available to make the wooden mold.

After attempting this, I cannot recommend going the route of bend, glue, bend, glue as described in the book. The best way I can figure - and it looks like jjhammerstein agrees - is to have the walls completely bent to the shape of the case before any gluing.

I suppose the good thing out of this (ironically) is that the epoxy isn't holding very well. I think I can remove the wall and replace it with a properly bent one sometime in the future.

Anyone interested in selling me a pre-bent wall? It's too bad Ben's kit doesn't include something like that, but now I know why it does not.

Website · Post by **Life of Brian** » Sat Dec 20, 2008 2:19 pm

What's the thickness of the aluminum you're trying to bend?

ckrtech · Post by **ckrtech** » Sat Dec 20, 2008 2:24 pm

1/16"

jjhammerstein · Post by **jjhammerstein** » Sat Dec 20, 2008 2:30 pm

All you need is a jigsaw.
You don't have one?

ckrtech · Post by **ckrtech** » Sat Dec 20, 2008 2:35 pm

Negative. I own no saws save a hacksaw that I just bought.

I am mostly a PCB, resistor, solder type of guy. ...which is most likely the reason why I am struggling so much with the case.

jjhammerstein · Post by **jjhammerstein** » Sat Dec 20, 2008 2:45 pm

ckrtech wrote:Negative. I own no saws save a hacksaw that I just bought.

I am mostly a PCB, resistor, solder type of guy. ...which is most likely the reason why I am struggling so much with the case.

You could do it with a hacksaw, without a doubt.
It will take a while, yes, but it's better than mangling your aluminum, right?
All you need is a couple pieces of plywood. You might even be able to get by with only one cutout, without even stacking.

hailrazer · Post by **hailrazer** » Sat Dec 20, 2008 5:51 pm

If you need the aluminum to be curved into sort of a hemisphere shape, then you need something round to bend it over.

Let's say you need a mild curve. Use a large coffee can or paint can. Bend it over that and you'll have a nice curve.

Now aluminum will spring back some, so use a curved surface smaller than the curve you need. An easy way to tell if the curve is right is to just set the can on top of the area where the aluminum is going, and then see if it is curved slightly more than you need. If it is then you are good to go.

Ben Cebhrem · Post by **Ben Cebhrem** » Sat Dec 20, 2008 6:20 pm

When curving any metal, having a solid surface is key. Using equal and strong pressure on the side that is not getting bent (the anchor point), and a greater force on the bending side (also equal pressure; very important!) is key to getting nice results. If you don't have a vice or clamps, using hardcover books and a person on top of them can get you an okay right angle bend; scoring the metal with a knife or hacksaw can also make this easier and neater in the end, but also weakens the metal.

EDIT: Just re-read what you wanted: a curve. Cool. Make some light scores at equal distances to each other. DO NOT go deep with them, they are just score marks. Use the method I posted above with the books, or the can method, and you'll get pretty good results- it'll look better than a right angle at least.

ckrtech · Post by **ckrtech** » Sun Dec 21, 2008 2:44 am

My next goal is to try and remove what is already glued to the front plate. The epoxy hasn't been that great. I hope that means I can remove it.

I'll try to start recovery from there. Salvage the metal strip by using something to bend it around. I would definitely like to get it completely formed before attempting to glue it to the front plate. I may need a new strip just to start with something clean and unwarped.

This has frustrated me quite a bit. I am going to spend a bit of time away from it - probably up past Christmas - just to make sure I keep my emotions away from clouding rational thought. Either way - I definitely need to use the best thing to create the shape I want while also keeping the metal straight.

jjhammerstein · Post by **jjhammerstein** » Tue Dec 23, 2008 6:50 pm

keep us posted.