diy metal folder /brake -sharp bends

[steveo3002]

ive seen the various sheet metal folder plans online - the ones that are basicly 2 bits of angle to clamp steel and another hinged one to fold up sheets of steel for diy jobs

id like to have a bash at making a basic one - one question whats the key to getting a sharp bend vs a more rounded one? id like to be able to make nice sharp bends

thanks

 

[Richard.]

The sharpness of the bend depends on 2 things.
The gap extension on your hinge point which should not increase as you move it and the sharpness of the top clamp. Your hinges need to be set into the steel not on it or it doesn't work.

 

[steveo3002]

righto...seeing folk are making them from angle , should i try and tickle the edge with a grinder to make it sharp ish?

 

[Wendelspanswick]

The biggest downfall with those kind of benders is they flex in the middle, increasing the gap, resulting in crisp bends at the ends and a bigger radius in the middle. I built a couple of the same design, the original 600mm long one worked OK'ish and then I built one that was 1600mm long to bend copper roofing sheet. Bearing in mind that the copper was soft and only 0.7mm thick the amount of bracing I had to weld to the folder to stop it flexing was ridiculous, especially as I had used 4" x 2" x 1/4" angle.

 

[steveo3002]

was thinking no more than 18" long ....cant see me making much over that size

 

[Wendelspanswick]

As Richard said, the centre line of the pivot needs to be in line with the bending edge, also you need to set the top edge (the corner the metal actually bends round) back from the bottom edge the thickness of the material or make it adjustable if your going to be bending different thicknesses otherwise the moving edge will be forced away from the material resulting in radiused bends.

 

[gordon stephenson]

As per above, What thickness are you needing to bend? The sharpness of the bend depends a lot on the gauge of the material being used,

 

[steveo3002]

car repair panels - so i guess 0.8 to 1.00mm or so

 

[steveo3002]

take this one for example...looks alright then skip to 10:50 and the bend isnt tight at all , what has he done wrong there? id not be happy with those bends

 

[Richard.]

They ain't too bad really. They could get sharper with a tighter corner on the top clamp and as wendel said by reinforcing the top clamp to completely restrict any flex. Mine are ok from my diy bender but not miles tighter than his to be fair.

 

[steveo3002]

can you show a pic of your bender please?

 

[Richard.]

Sure. She ain't pretty. Made her as an apprentice and it's had some steel slapped on her in recent days to stiffen the top clamp for 1.5mm stainless.
Does a decent job though so I've no need to change it just yet.

 

[outofthefire]

For up to 18" of the thickness your using Id just use a couple of bits of angle, pull the bend by hand and finish it with a mallet or planishing hammer

 

[gordon stephenson]

If you did need a really tight bend,You could always score the metal a little with a very thin cutting disc by just a few thou.It would give it a slightly weaker spot to bend at,

 

[optima21]

here's mine, I didn't make it,I bought it.

the pivot centre is on the edge of the angle that is used as the base.

the top face of the bending bit with the handle on it is machined flat

and the clamping angle is adjustable with the from edge being about 2mm tall and machined flat,and then machined at 45 degrees so you can see what you're doing.it is also slotted so you can adjust the bending point for different thicknesses of metal. bent 150mm lengths of 2mm thick on it,but it was only supposed to be used for 1.2mm max thickness

 

[mike 109444]

This link http://retrorides.proboards.com/thread/70135/panels May help with the panel making and also shows another twist on the folder.
The pics attached shows a means of adjustment (not mine I must point out) It also shows the way that the pivot is positioned. The center of it's pin has I think to be at an imaginary line at the radius of the bend it that makes sense !

 

[Richard.]

If you did need a really tight bend,You could always score the metal a little with a very thin cutting disc by just a few thou.It would give it a slightly weaker spot to bend at,

A little nick out of the edges with a slitting disc helps too once folded you can always dab em back in with the welder.

 

[gaz1]

you could take a look at these

http://www.mig-welding.co.uk/forum/threads/diy-press-using-rsj.68256/#post-898073

http://www.mig-welding.co.uk/forum/threads/home-made-press.66666/#post-868780

http://www.mig-welding.co.uk/forum/threads/homemade-bender.60504/#post-749674

 

[eLuSiVeMiTe]

you could take a look at these

http://www.mig-welding.co.uk/forum/threads/diy-press-using-rsj.68256/#post-898073

http://www.mig-welding.co.uk/forum/threads/home-made-press.66666/#post-868780

http://www.mig-welding.co.uk/forum/threads/homemade-bender.60504/#post-749674

Go up to post #12

 

[graffian]

The biggest downfall with those kind of benders is they flex in the middle, increasing the gap, resulting in crisp bends at the ends and a bigger radius in the middle. I built a couple of the same design, the original 600mm long one worked OK'ish and then I built one that was 1600mm long to bend copper roofing sheet. Bearing in mind that the copper was soft and only 0.7mm thick the amount of bracing I had to weld to the folder to stop it flexing was ridiculous, especially as I had used 4" x 2" x 1/4" angle.

I can't remember how tall the sections are but it's almost rigid enough, maybe twice the section height would do it;-)
It's all bolted together so I can easily pull it apart to use the steel for something else, and I can move the centres around and
move the clamp back to vary the radius.