Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Tooltray - how to bend aluminum?

After my more or less progress in bending Alluminum a friend has an eye on it (it looks a little bit like a banana).

He is a professional. He works at a well known factory as an „Industriemechaniker“. If all machinery is running they have time to play.
With high quality big stuff and tools. He says: tell me what you want.

In my construction where three mainsheets. One is a little bit difficult an needs a three (or four) time bending. With the banana in sight I give him the details for the „sheet 3“. Less than 12hours later I‘ ve got it.

A great step forward. And: he can use a (very) big electric-hydraulic press. But one bend must do on an old basic handwork press.

Today he told me to bend the 1.5mm alloy by hand (with a highquality) tool needs a lot of muscle.

So in review: bend 2.0mm as a DIY, forget it. Bend 1.5mm at home? Worth a try, it hard work.

With this knowledge the mainsheets are done, now forward with 1.0mm.

René

It's a learning curve Rene, but well done so far!

Yes.

René

You have to bend perpendicular to the rolling direction. Have a look on the tiny lines of the sheet.

This. ^^^^^^^^
The rolling process creates directional strength differences. The sheet is stronger along the length than across the width, basically due to stretching during rolling in that direction aligning the microstructure along it. Think of a fibrous structure as an analogy.
The effect can be reversed for a more uniform length versus width strength by annealing. Cold rolling increases it.
With the aluminium sheet you are likely to buy the differences will be negligible and probably not noticed. Repeated bend/unbend should be avoided as that does weaken the metal in the bend area.
Have you been to the MMC factory? The panels are cut to a template and fitting is done with hammers (panel beating types), shrink forming also in situ on the car with filing/sanding to get the desired surface finish. What you will be doing bending sheet will likely be less of an effect than panel beating.

OhOh...

German overengineering or fear? Thinking and thinking, reading a lot of information. After a struggling way and a hilly learning curve... I just open Mr. Ws book now.

Ups, as I see now most informations there 1.2mm

As a german speech says: wer lesen kann ist klar im Vorteil. Something like: who can read got a benefit.

René

My view is that 2mm sheet aluminium is required to give the tool tray adequate rigidity, given it will be carrying a wheel jack, hammer etc. As DaveW points out this is too stiff to work with easily at home without a press, hence my suggestion earlier. Other TM'ers as well as myself have had aluminium trays made professionally, and all to my knowledge have used 2mm.

To quote Clint Eastwood "a man has to know his limitations"

I wonder if scoring a vee along the line would help, I use this technique to get a sharp fold in brass & copper, but then this is ultimately soldered, some alloys take two pack epoxies for bonding very well

There are two choices for bending the aluminium.
Use a proper bending tool that can be bought fairly cheaply. It will have limits on the size you can bend. It will give a decent straight bend. There are details of how to measure where you bend to get accuracy. You could make your own and you tube has examples (some are crude ). Also, how tight a curve do you need in the bend? This is where you can make things easier or more difficult in getting dimensions accurate! Bending over a rounded or curved former can do this to avoid tight bends, even just pressing the sheet by hand in some cases.
You can use a mallet or hammer but that takes practice to get a good finish.
As regards the different strength depending on direction....it is standard practise to test strips using samples taken in both directions during rolling. Tensile strength is the one that shows differences. Hardness is unaffected as it is on a specific point that orientation doesn’t affect. Bend tests will show small differences that will depend on the rolling temperature and amount of thickness reduction.

For me the challenge was to make a tray at home, and so I had to compromise on thickness. My bending rig is two lengths of timber, a vice and two G clamps.

Sometimes I use my jack handle, which is a large diameter aluminium tube.

The easiest way is to build it up in sections, which is how my third tray evolved. Given that the flimsy plastic tray holds the tools reasonably well, 1.2mm, or 1.5mm will do the job for the DIY fabricator.

There's quite a difference in working 1.2mm and 1.5mm, and inevitably some pieces get scrapped, but that's all part of the fun!