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You need a minimum internal bend radius to prevent weakening the material. I'm sure a 150mm long bend in 5mm mild steel is a 10 ton pressbrake job. What tools do you have available?
Beat me to it.BFH
And a big vice to hold it.
And these days, now I'm sensible, ear defenders.
oldbikedavey
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If it's mild steel sheet, it won't crack.
Can be done in a hydraulic garage press of 'suitable' power, given a bit of thought and preparation.
Can be done in a hydraulic garage press of 'suitable' power, given a bit of thought and preparation.
BrokenBiker
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do you have heat? i assume not if you want to do it cold? if not, do you have 10 ton press? or can you make one from a bottle jack and some scrap?
how close to the edge is the bend, how critical is the angle? do you want to do it in 1 process or are you open to scoring it say 3mm through on the side that will be the outside of the bend then bending and welding back up?
how close to the edge is the bend, how critical is the angle? do you want to do it in 1 process or are you open to scoring it say 3mm through on the side that will be the outside of the bend then bending and welding back up?
doubleboost
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Put a grove in with a slitting disc bend it then weld it .
8ob
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That would bend ok with a bit of tooling in an ordinary hydraulic press, I knocked up something that could bend over a foot long bits of 1/2" plate and that doesn’t crack.
Bob
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I did some twice that length on my hydraulic press, to make a new baffle for our woodburner, using two steel dowels welded to a plate to press against, and a piece of plate with a bullnose ground on it for the ram to push against.
I welded the bullnose piece on each end to the plate along the line of the bend, then bent it bit by bit by moving it along the press.
Or you could do as Doubleboost suggests, and put a groove in, bend, and weld.
I welded the bullnose piece on each end to the plate along the line of the bend, then bent it bit by bit by moving it along the press.
Or you could do as Doubleboost suggests, and put a groove in, bend, and weld.
premmington
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That works - plus you get the bend where you want it - and you can get tight bends.
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Surprising how easy it is to get mild to crack.
Things like very tight rad bends, stress raisers like scribe lines, burrs from shearing and even grain direction can all cause it.
Unless you have access to a hydraulic press, or want to make a machine, I'd just cut the outside half way through, bendand weld up. Over bend slightly to allow for the weld pulling back.
Probably looking at a 10t press, depending on die openings etc. 5 would probably do it at squeeze.
Things like very tight rad bends, stress raisers like scribe lines, burrs from shearing and even grain direction can all cause it.
Unless you have access to a hydraulic press, or want to make a machine, I'd just cut the outside half way through, bendand weld up. Over bend slightly to allow for the weld pulling back.
Probably looking at a 10t press, depending on die openings etc. 5 would probably do it at squeeze.
Erie Fred
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Here is a common chart that puts real numbers to the OP's question:
Please note the various tonnages for the same thickness, the highlighted one uses the recommended
8x die opening (for 1/4" and under), you can go bigger for less tonnage (but need a longer leg) or go smaller opening for
a shorter leg, but need more tonnage.
Meanwhile, my neighbours have ringing ears, my under-used left arm is aching, the cats are upstairs under the bed, the lump hammer is warm, but I have 6 bits of bent a 5 thk steel, with a 10 -ish rad at the bend.
Not a set of saleable bits, but well usable on a DIY construction.
Not a set of saleable bits, but well usable on a DIY construction.
I do remember some of our lads wondering how to get something in a brake at work to create something unusual.
Being a bodge-artist with no gear at home, I could see other possibillities - so me, a vice and a big hammer . . . Been known to use lamp posts,gaps in the paving, my bed (an elastic, varying radius folder, that with the assistance of my mum, created the bonnet for my Lotus 7 replica when I was aged around 19).
I do miss that place of work though - no equipment and no possibility of govy jobs now at the place I've been at the last 20 yrs, so I've had to buy some equipment of my own.
Being a bodge-artist with no gear at home, I could see other possibillities - so me, a vice and a big hammer . . .
Been known to use lamp posts,gaps in the paving, my bed (an elastic, varying radius folder, that with the assistance of my mum, created the bonnet for my Lotus 7 replica when I was aged around 19).I do miss that place of work though - no equipment and no possibility of govy jobs now at the place I've been at the last 20 yrs, so I've had to buy some equipment of my own.
