Not another Metal brake :D

[gaz1]

@Welderpaul his bender on the forums with sizes

http://www.mig-welding.co.uk/forum/threads/mini-sheet-metal-folder.3710/#post-37887

450mm wide 2mm thickness to bend so an adjustment up to 600 is possible as long as you drop your thickness

 

[Richard.]

I made one years ago. For up to 1.5mm over 600. Still got it.
Simple design that’s been used over and over. To bend something round a curve in the same fashion is not difficult providing your top clamp is cylindrical . Your leverage plate would need to be a roller really so that as you apply the force on the sheet it would roll the sheet around the top clamp. I think you’ll struggle to get the sheet to the radius of the clamp though because of spring back. To be honest a home made set of slip rollers would be a far more effective way to do this screwdriver rather than making life harder redesigning a piece of equipment that is never going to work as well.

 

[Richard.]

Oh and I’m not sure if this is important or not but if you wanted to roll different radius’s in this fashion you would require different radiused top clamps and your pivotal pressure roller would then need to be height adjustable so that it followed the contour of the top clamp as you made it bigger and smaller.

 

[Richard.]

Something like this @Screwdriver
Would be easy enough to make and adopts a similar approach to a folder.
Now like I say your not going to roll the same rad as the clamp it’s always going to spring back some but if you undersize the clamp and do a bit of trial and error work you could soon find out what clamp finishes off with what radius on what materials and gages and just note it down.
In theory there is no reason you couldn’t roll a close to 360 this way with a couple of repositional moves of the sheet. But it’s exactly as you say it’s a crude way to do it but yes it would work.

 

[Screwdriver]

Yes I am running through a number of designs but I can't get away from two issues:

1. The die would need to be solid and approximately the diameter of the target curve
2. Three rollers is better than two as per the typical setup (complicated by the need for a geared, driven system)

I am thinking of a relatively crude method which would be much more simple. It would need a lot of leverage (easy) and the precise curve would be determined not by the accuracy of the die but by accurate indexing. It would not need to produce a perfectly smooth curved surface because a slightly "rippled" cylinder would give it a little bit more strength for my purposes (like a garbage can).

 

[Richard.]

I don’t think your going to get much simpler than what I’ve drawn. The die would not need to be solid some heavy wall pipe blanked off on the ends would do. The pressure roller could be heavy wall pipe also with a couple of bearings pushed in either end.
Leverage as long as you like.
Ref the sheet matching the radius of the die it’s not going to happen. If you want that you need a set of rollers.
If it’s a crude roll your after I don’t see how that matters. You just undersize the die to suit. Pull it back a bit if it goes too far.

 

[Screwdriver]

I don’t think your going to get much simpler than what I’ve drawn.

Wanna bet?

I wouldn't have a design that needed a slot and I would ideally lose the hinges/bearings too. Don't need them. All that is required is a long lever and a pivot, anything else is mere complication...

I am currently working on something where rather than bend the metal directly, the lever acts on a free roller which wedges against the sheet, amplifying the effort. The die could be a stack of old car tyres or similar depending on size required or even a wooden former with just a slight radius rather than a full circumference.

 

[gaz1]

the answer is yes

https://www.thefabricator.com/artic...ake-or-plate-roll-the-right-tool-for-the-job-

the pic is from a press break



when bending you would have to factor in spring back as well as enough bend of the material so it would keep its pre rounded shape per bend

 

[Screwdriver]

That is amazingly accurate for such a long length of relatively thick material. Nice!

 

[gaz_moose]

so has anyone ever made a box and pan style folder?? I made one like kim's ages ago but find I always end up needing to make weird shapes so end up hammer forming some of the folds.

 

[Richard.]

That is amazingly accurate for such a long length of relatively thick material. Nice!

But look at the machine screwd. It’s a monstrous press break. I’d I’d expect it to have no problem doing that.
You could achieve the same thing exactly on a smaller scale with a few different options. Small Press break, hydraulic press or a fly press could do exactly the same thing if you put the right tooling on it.

 

[mike 109444]

Yes I am running through a number of designs but I can't get away from two issues:

1. The die would need to be solid and approximately the diameter of the target curve
2. Three rollers is better than two as per the typical setup (complicated by the need for a geared, driven system)

I am thinking of a relatively crude method which would be much more simple. It would need a lot of leverage (easy) and the precise curve would be determined not by the accuracy of the die but by accurate indexing. It would not need to produce a perfectly smooth curved surface because a slightly "rippled" cylinder would give it a little bit more strength for my purposes (like a garbage can).

You could use some scaffold tube, axle through middle and fill with compacted/vibrated concret to give the "solidness" you need.
Get an old wash mangle (ex garden orniment!) and use the gear assembly from that. Usually cast steel or iron

 

[Screwdriver]

But look at the machine screwd. It’s a monstrous press break. I’d I’d expect it to have no problem doing that.
You could achieve the same thing exactly on a smaller scale with a few different options. Small Press break, hydraulic press or a fly press could do exactly the same thing if you put the right tooling on it.

I am considering my options with the flypress. 600mm is too much stick out and you can't roll a full cylinder. But I have a cunning plan. Having discounted the idea of having two flypresses either side of the workshop (!) I could build an extension to the ram and roll a cylinder underneath the press with the bottom die on the floor. Only two slight issues; 1. there's a ton of junk under my flypress and 2. I haven't seen the floor in my workshop for several years...

<edit> Here's the plan:

Not seen anything like this before so be interested to hear if anyone else has ever thought of it or (more likely) why it wouldn't work in the first place...

Clearly the base would need to be firmly bolted down!

 

[Screwdriver]

You could use some scaffold tube, axle through middle and fill with compacted/vibrated concret to give the "solidness" you need.
Get an old wash mangle (ex garden orniment!) and use the gear assembly from that. Usually cast steel or iron

I have some long lengths of suitable bar stock from a job lot/shed rescue. I'm saving them for something special

Since I commonly fix motorcycles and have more spares than I care to count, I have tons of chain and sprockets etc. What I don't have is the time to build yet another machine to do a job which helps me build my forge. I have decided to make a biscuit tin forge™ first and worry about forming cylinders later or maybe when I have an empty gas bottle.

 

[Richard.]

I am considering my options with the flypress. 600mm is too much stick out and you can't roll a full cylinder. But I have a cunning plan. Having discounted the idea of having two flypresses either side of the workshop (!) I could build an extension to the ram and roll a cylinder underneath the press with the bottom die on the floor. Only two slight issues; 1. there's a ton of junk under my flypress and 2. I haven't seen the floor in my workshop for several years...

<edit> Here's the plan:

Not seen anything like this before so be interested to hear if anyone else has ever thought of it or (more likely) why it wouldn't work in the first place...

Clearly the base would need to be firmly bolted down!

Each to there own. I fail to see how that is indeed more simple or certainly effective.
For one the length of the thing I see stability issues and getting a straight punch not to mention over that length how much actual power you’ll lose out of the tool.
I thought you wanted a simple solution. If your gonna just do a one off or a bodge why don’t you force the sheet round a large pipe with a couple of ratchet straps and tack it shut. That’s the simplest crudest solution but will likely give better results that what you show there

 

[Screwdriver]

Each to there own. I fail to see how that is indeed more simple or certainly effective.
For one the length of the thing I see stability issues and getting a straight punch not to mention over that length how much actual power you’ll lose out of the tool.
I thought you wanted a simple solution. If your gonna just do a one off or a bodge why don’t you force the sheet round a large pipe with a couple of ratchet straps and tack it shut. That’s the simplest crudest solution but will likely give better results that what you show there

Sorry didnt realise you'd had a sense of humour bypass. Glad to hear it was so successful.

I was merely wondering out loud if there was or if anyone already had designed a manual press brake for forming cylinders. Your sketch is basically two circles and a slotted rod, I appreciate the effort but it's not a solution.

The Flypress tooling is a winner I think. I am outlining the idea in my crude sketch, clearly it would need simple guides each side of the drop arms and some reinforcing bars to prevent racking but if it works, it would make the Flypress an amazingly versatile tool for forming cylinders of any size up to the height of the deck.

 

[Jetex]

I am thinking that your flypress idea will not be stable enough to get any kind of accuracy needed to make a cylinder unless you add substantial side guides to the forming frame to stop any side movement. You would be much better off trying to build a simple slip roller for making cylinders out of sheet metal.

 

[Richard.]

I appreciate the effort but it's not a solution.

It is a solution. It’s a tried, tested way of rolling. (How do you think tube benders work????) Like most threads you ask questions in it’s just not your solution so it would never work. Begs the question why ask if you know all the answers. People are gonna get sick of replying if all ideas are gonna be second guessed by the pro. If you want to quadruple the length of your fly press arm with a bit of box section by all means fair play to ya but simple it ain’t. You’ll need so much weight on the thing to make it rigid it will probably take more effort to retract it than it will to take your punch. Then you need to guide it straight and stable from both sides as you say. While your operating the press who is down on the floor keeping the sheet in line and watching the bend angle? Hell if your gonna go to that effort why not just build the right tool for the job. It would be easier to build slip rollers but I guess they are not a proper solution either cos its just 3 cylinders and a handle.

 

[Screwdriver]

It is a solution. It’s a tried, tested way of rolling. (How do you think tube benders work????)

I know how they work thank you and I could build one but 1. I don’t really have the time 2. It has limited use for me currently 3. I don’t have the room for a dedicated roller.

Your simple two circles and a slotted bar is really of no help and I can’t understand why you are getting so defensive about it.

Like most threads you ask questions in it’s just not your solution so it would never work. Begs the question why ask if you know all the answers. People are gonna get sick of replying if all ideas are gonna be second guessed by the pro.

OK so we’re on to personal attacks. Fine. Rather than rewrite history to suit your argument, here is what I actually said:

Could something like this be converted to produce a relatively crude curve bending mechanism to make cylinders? I appreciate a triple roller is preferred to form a continuous curve but that is an order of magnitude more difficult to build.

I was interested because I could fit a unit like that along the front of an existing bench. Easy to make with space available as required.

Has anyone made one do you know? It would be for 1.5mm sheet, max 600mm wide so I can make cylinders and pipe, maybe even the odd flue.

I was interested in hearing from someone who had made one. I was not asking for ideas or fantasy, I would be very surprised if there wasn’t already something out there. Anyone in this forum could come up with “an idea”, they are two a penny. Making it happen is the trick.

If you want to quadruple the length of your fly press arm with a bit of box section by all means fair play to ya but simple it ain’t. You’ll need so much weight on the thing to make it rigid it will probably take more effort to retract it than it will to take your punch. Then you need to guide it straight and stable from both sides as you say. While your operating the press who is down on the floor keeping the sheet in line and watching the bend angle? Hell if your gonna go to that effort why not just build the right tool for the job. It would be easier to build slip rollers but I guess they are not a proper solution either cos its just 3 cylinders and a handle.

Ah so now because I don’t like your idea, you’re rubbishing my idea?

Ok since you ask: Two “drop arms” running down the side of the existing solid table would not require any extra room nor would they add that much weight. They would be in compression and could be made from lightweight tube (something like motorcycle fork legs). Whatever the drop arms are made from, they would just need to be restrained with a simple guide.

Retracting the tool on a flypress would be trivially easy. Remember, it can develop several tons of downwards pressure due in part to the magnifying force of having a screw thread. That magnification of effort (to lift a few extra kg) also works in reverse. The size and weight of a press tool is whatever it needs to be to perform the desired function. It is not a valid criticism to simply say it would have to be too big and heavy. It would be whatever size and weigh was required, in this case for 1.5mm sheet (as I said earlier).

It might be more tricky to align a sheet on the floor but in practice, not that much more tricky than manipulating a large sheet of material three feet off the floor! Alignment and keeping it aligned is a detail problem easily solved in a similar way to how most press brakes work, with a spring loaded hold down blah blah. It is no more difficult than existing, known methods.

The flypress is an amazing tool and you don’t have to ram the thing like a steam hammer, they are surprisingly controllable and can exert tremendous force with a very delicate touch. Bends aren’t necessarily banged out in one fell swoop but can be made with a succession of accurate, targeted blows.

Anyway, I refute all of the allegations made in your post including your criticisms of what I consider to be an interesting idea for upgrading the capability of my flypress. It takes up so much room in my relatively small shed, the more I can get out of it the better. I started off by being quite humorous in my reply and I really don’t know why you have decided to act so aggressively towards me or make up a story about my initial response to this thread.

 

[Richard.]

Don't need them. All that is required is a long lever and a pivot, anything else is mere complication...

Makes me laugh. At first mine was too complicated and this was the goal at the beginning of the day.
Now we have really stepped it up into proper fantasy land.

you’re rubbishing my idea?

Your idea is rubbish. I’ll say it as it is I’m sure others will be more friendly about it but they will indirectly tell you it’s rubbish too. Mine wasn’t an idea it was a solution that is commonly in practice. I didn’t think of it. I put it forward. I don’t care if you don’t like it but it’s insulting to think that you believe that contraption on the end of your fly press is a Better solution.

. I was not asking for ideas or fantasy

It’s clear Your not interested in listening to others ideas your right there. I’m just hoping people read that clearly and think twice about sharing cos it’s not uncommon in your threads to see this.

to lift a few extra kg)

It would be whatever size and weigh was required, in this case for 1.5mm sheet (as I said earlier)

No clue whatsoever on the forces involved and the strength required to bend 1.5 over 600. The fly press is up to it but “a FEW extra kg” of metal work. Ok I’ll let you go to work on that and find out the hard way as it’s not something you’ve had much to do with. Put it this way what you have drawn would fold and flex like a crisp packet. All the force on the one central point. If you were to build it with enough beef to do the job (far more time consuming than any other method mentioned btw)
It would weigh a lot more than a few extra kg. I’m done here. I thought it was a good topic to start but it’s gone from engineering to clueless to insulting.