Making a Brake with a soft corner for Aluminum.

[Leatherneck]

I have some aluminum sheet metal and I don't want a sharp corner on it, I would like to build a brake with a softer corner to it and figured one of you geniuses could help me do that. So any ideas on making one? Thanks!

[winifredevw]

What if you just make multiple bends on a brake, close together? It won't be the smooth, round bend that you're after, but pretty close though.

[SCOTTRODS]

How large of a radius are we talking here? if it's just to knock off the "sharpness", there's a way to use an existing break and get the break more round..... but if we're talking about a 3 inch radius or something that direction,.... you will definitely be building something or finding someone who has a long Roller. I used to use a 3 foot roller for similar actions, but I have seen some even longer ones, so I know it can be done reasonably with a roller as well.

Worst case scenario, this discussion(Or one very similar) came about just this week or last, the answer came about to Clamp a pipe of the diameter/radius you desire, to the metal and work it with a soft mallet over the pipe.... or even to cut another pipe of larger diameter to clamp it down and form it.... There are more ways as well.... how big is your radius desired?

[Leatherneck]

No nothing huge, probably at most a 1 inch radius, I just don't want the sharp bend of a normal brake.

[Ol'fogasaurus]

Leather:
Clamp a 2 X 4 or better yet a 2 X 6 (the width of the sheet/distance you want to bend) over the start of the bend (more clamping/holding surface) on the top/outside surface of the sheet. Using another 2 X 6 radius one edge of the 2 X 6 to the radius you want then clamp the two-by to the underside (the direction you want to bend to) of the sheet with the start of the radius on the two-by at the same point you want the bend in the sheet to start.

Using an angle finder set it at the angle you want to end up with as it will be your guide. You will have to bend the sheet a couple of extra degrees because of “spring back”. Try this on a piece of scrap first to see if it will work and to see how much spring back you will get.

Clamp the two two-by to the porch/table or whatever then you can either push down or lift that way; just be careful and do it slowly and it small amounts. I think I would have a tendency to put another pair of 2 X 4s clamped together with the sheet in between close to the bend to help keep the sheet flat at the bend.

If this doesn’t make sense it’s because I am tired but you should get the idea.

Lee

[turbobaja]

You could put a couple bottle jack tube-kinkers to good use like this. Worked for me .



A little pre-stressing while welding up the main truss supports.



I ended up with a pretty tight radius on most of the bends, but with a larger, more rounded formed edge on the upper press beam it would be easy to widen the radius for a less-stressed bend area.





There's a few more pics and a lot of good input from Foggy and that crazy guy NutSquad too in my build thread .

[Ol'fogasaurus]

That is pretty nice way of going but I didn't want to confuse him with router radiuses and the like.

The male and female parts of the bending machine determine the radius of the bend but you can let it form more natural, kind of like Turbo did when you don't go completely into the die; the bad part can be that you are not always guaranteed of a constant radius and bend radii because of any slippage/miss-alignment in the tool (not being perpendicular throughout the entire bend application).

Originally I started out my write-up by talking about marking the OMLs (both tangents of the bend [OMLs]) and the centerline of the bend (CLB), or marking them with tape but it started to get too technical so I deleted it. If you want to do it correct and on the cheap (a wide break press) correct Turbo has it very close and I would defer to his way of doing things (his markings on the piece of sheet are for hydro pressing but it still would work here) but I think I would add some round stock between the upper and lower pieces to ensure that things stay straight with maybe some valve springs to separate the anvil and press smoothly. It sure looks hell-bent for strong!

Lee

[Iguana]

I have some aluminum sheet metal and I don't want a sharp corner on it, I would like to build a brake with a softer corner to it and figured one of you geniuses could help me do that. So any ideas on making one? Thanks!

Have a look at these Magnetic Brakes, might not be what you are after but the main thing to consider in the impact different tooling can make to a bend. If you are only talking alloy it is pretty soft and leaves a lot of options open.

The Magnetic ones will do up to about 12ga Alloy.

[Iguana]

You could put a couple bottle jack tube-kinkers to good use like this. Worked for me .

There's a few more pics and a lot of good input from Foggy and that crazy guy NutSquad too in my build thread .

Just wanted to say .. Damn that is impressive