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View Full Version : Bending metal 90degrees - press brake or something else?



Doozer
06-03-2018, 02:15 PM
Anyone know a place in Calgary where I can get a few small pieces of about 1mm thick metal bent 90 degrees? I actually need 4 straight pieces bent into a U shape, and I've tried with my vice at home and can't get anything remotely close to a straight bend.
Or if you've got tips for rigging up something at home, I'm listening. The pic below shows what I was able to accomplish with 1 piece in about an hour, and it's unusable.

Thanks!
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firebane
06-03-2018, 03:14 PM
Flat bar, c clamp and a hammer.

Doozer
06-03-2018, 03:23 PM
Flat bar, c clamp and a hammer.

Yeah, I might try that but there are still several obstacles. No flat bar, so I'd have to go buy some in the right width. I'd still have to mount it somewhere (like a vice) in order to bend it over with a hammer. Tried that. The first bend is manageable, but trying to get that second part of the U, without a vice, is almost impossible (unless there's some technique I don't know about).

ExtraSlow
06-03-2018, 04:46 PM
How strong do you need it? A cold chisel to score the inside of the bend would help it bend cleanly. Would slightly reduce strength.

Whatcha using it for? We may be able to think of alternatives.

Doozer
06-03-2018, 06:56 PM
I've thought about scoring - it doesn't need to be super strong. I don't have any spare pieces other than that first one I already experimented with so I want to be sure for the next one.

As for purpose, I would love to hear alternatives because I've got nothing so far. Well, nothing better anyway. And I can't believe something out there doesn't exist for this exact purpose because I'm definitely not the first to need it. It's basically going to be a pivot point. The middle part of the "U" will be screwed to a plate on the ground, with an axle going through the holes holding a rounded piece of wood, that will allow the wood to rotate freely. Right now I'm mocking it up with some spare fibreboard, but the pic might help a bit. There will be an axle that goes through the wood and the top hole in the metal, attaching on the other side.

I've thought about using wood blocks to hold the axle, but that's adding a lot of bulk and weight for something that shouldn't need it. And the mount doesn't have to be super strong, it's basically going to swing out with minimal stress on it. But for the love of all that is holy, I just cannot find any simple way of making a pivot point for that piece of wood that doesn't add a bunch of weight.

Now, I HAVE thought about 2 L-shaped brackets facing away from each other, but the problem with that is that the outside bracket will add an inch or whatever of width to the baseplate that I really don't need. I'd like to avoid that if I could.


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03ozwhip
06-03-2018, 07:56 PM
Heat it and bend it. It won't take much heat but maybe score it first, heat up the score and see what happens.

ExtraSlow
06-03-2018, 08:13 PM
Could buy some rectangular tube of the right dimension (if it exists) and just cut an inch bit off the end. That may end up no easier.

s_havinga
06-04-2018, 02:21 PM
I would bend the first 90 in the vice and then clamp it to the "arm" and use a hammer to form it around the wood. That's pretty thin stuff, you should be able to get it damn close using this method.

Doozer
06-04-2018, 11:19 PM
Yeah, that's how I got the U shape that I showed in the first pic. Took a long time, and sides aren't even. The worst part is that if the bends aren't close to perfect, the holes don't line up. I may have to try the heat method and see if the softer metal makes it work. Not sure what the residual strength left will be though.

Maxx Mazda
06-04-2018, 11:58 PM
The heat will help immensely. My advice is to find some sort of metal “form” in the same shape you need and use that.

lamp_shade_2000
06-05-2018, 12:03 AM
Could you just buy a perforated square tube and cut one side off toake your U shape?

https://www.lowes.ca/metal-products/hillman-3-ft-x-1-in-plated-steel-perforated-square-tube_g1191258.html

Cword
06-05-2018, 08:03 AM
Don't make your first bend 90
work both bends to 45 or 60 depending on the amount of room your vice jaws allow.
If you get nice sharp shallow bends you'll have an easier time working them both to 90 than doing one and then trying to do the other.

Doozer
06-06-2018, 09:29 PM
Could you just buy a perforated square tube and cut one side off toake your U shape?

https://www.lowes.ca/metal-products/hillman-3-ft-x-1-in-plated-steel-perforated-square-tube_g1191258.html

I thought about that, but I'd need way too big of a tube. The holes have to be 2.5" off the bottom of the U, so I'd need to find a tube that's 3" X 1" rectangle. It'd be easier to just find the U shape to start with, than the weird rectangular tube.

But, sometimes the simplest answer is staring you in the face the whole time. I ended up clamping my vice grips in my vice, and then just evenly hammering the ends down. Initially I didn't try this because the rubber vice grip handles kept getting in the way of clamping, but I ended up finding a sliver of metal that the vice could grab onto, and then I steadied the vice grips with my free hand.

The bends aren't perfect, but took me all of about 5 minutes to do, and we'll see if these are usable.

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