Bending 4mm aluminium 5083 box and pan

[robert-shetland]

Hi All,
Have posted something similar to this before, but i am now working with aluminium boats, with a build happening in the next couple of weeks.
I have to get 90 degree bends in 4mm 5083 aluminium, only 2 on each boat that size and the rest are small, 1m and under.
I can get access to a press brake for a fee in another workshop so i could use that but will take time and will cost a bit.
I am looking at options just now, would an old fashioned box and pan folder work for this, say an 8ft one capable of 2.5m steel?
I have heard varying answers from people saying that a box and pan would create to sharp of a bend and possibly crack the aluminium, but others have said you can set the teeth back and make a bigger radius, also another option from working with smaller box and pan folders is to use a 2nd bit of say 2mm stainless in the machine to make the radius bigger.
Anyone thats got an 8ft folder be able to try this for me with a piece of 4mm 5083 to see if it can work?

Also lastly, if it would be a worthwhile investment, would anyone have an 8ft box and pan for sale? Not many around on the net anywhere at a reasonable price.

Thanks

 

[Brad93]

If you can adjust the offset of the beam or teeth to the folding edge then you may get away with it but 5083 is pretty tough, let alone 4mm. Really that’s a pressbrake job.

 

[robert-shetland]

If you can adjust the offset of the beam or teeth to the folding edge then you may get away with it but 5083 is pretty tough, let alone 4mm. Really that’s a pressbrake job.

Yes thats what i think its strong stuff, would be interested to try it and see, im sure it would be fine for the smaller parts, but the 3 large parts per boat 2m long i am not sure it would work. I can access a press brake but its a good drive each way and would be more time and money so was hoping i could pick up a second hand old box and pan, don't suppose you have one you could try this on do you?

 

[Paul.]

Really that’s a pressbrake job.

And with a decent radius tool too, 3 to 4 times the plate thickness as a rule of thumb, also it makes a difference bending with the grain or across it, Done quite a bit of it in the past with a pressbrake, you could have a pile of plates all bend just fine then suddenly one would crack for no apparent reason, a bit of lube on the bottom tool can help, urethane strip is also a useful thing to have on the vee

 

[Brad93]

And with a decent radius tool too, 3 to 4 times the plate thickness as a rule of thumb, also it makes a difference bending with the grain or across it, Done quite a bit of it in the past with a pressbrake, you could have a pile of plates all bend just fine then suddenly one would crack for no apparent reason, a bit of lube on the bottom tool can help, urethane strip is also a useful thing to have on the vee

Yep urethane is a must. I sub the Ali bending out to a friend with a 4m Amada. Not worth the hassle.

 

[hotponyshoes]

I don't think you are going to be bending 8' of 4mm by hand even with 2 of you if you could find a bender that would cope with it.

I have a solid 4' Edward's box folder and the max on that is about 2.5mm alloy. It would possibly take 4mm if you shimmed out the top clamp but I would not like to risk it.
2mm over the full 4' is a 2-man job although that's mostly because the sheet blocks access to the handle.

I have a 2'box/pan which is a bit more adjustable but 5xxx will crack on that unless I set it up carefully.
I suppose you could grind a radius onto the teeth or maybe even some sort of radiused capping strip could be used?

For the expense involved in getting the tooling to do it I would either outsource that job or just cut it and weld it.