Forming a Sheet Metal Flange

In days gone by when most bodywork was done by skilled 'Tinsmiths' with no modern machinery many methods of working existed which have largely been forgotten now, this is possibly one of them


The only tool you need is a length of 1/2” steel rod, about 6” or so long. In the end of this rod a slot is cut the depth of which is the same as the depth of the flange you wish to create. The slot, best cut using two hacksaw blades, side by side in the hacksaw, down the length of the rod. ( As shown in the picture ). My rod had a bend in it for a particular purpose, you can leave your rod straight or bend it to suit your self.




sheet 4



Having cut your metal to size, clean up the edge that you wish to form ( you should always clean up the edges of cut sheet, it is safer that way ! ) and slide the slotted rod onto the edge of the sheet where you wish to form the flange. Start at one end.






Lift the free end of the rod a little and the flange will begin to form, Do not lift too much, particularly if you are going around a fairly tight curve. Move the rod slightly further around the edge, overlapping the previous position and lift again the same amount. Repeat this process until you reach the end of the flange.







Now you go back to the beginning and do it all over again.

As you lift the edge the metal is either stretched (an inside curve) or compressed (an outside curve) so if the radius is fairly tight then you need to lift the rod a very small amount and repeat the whole process several time.

Always work your way along the whole length of the edge before repeating the process and increasing the bend.

Eventually you will have a flange which is at right angles to the sheet of steel and closely follows the curve of the edge, just like magic !

 Patience is all that is required.





In my case I proceeded to roll the edge by taking the flange past the right angle by continuing the bending ( I had relieved the back edge of my tool. ) and then folded down the edge using a hammer. It took me a little over 10 minutes to create two plates.








This article, written by Malcolm Watts,, originally appeared in CA7C Seven Focus in Aug 2002 pp 22-23.