A lot of This is Incomplete


Sheet Metal Folder

I made my first metal folder to fold aluminium for a race car interior. This involved pieces of 22 swg aluminium up to 4' long. It coped with 4' of 22 swg steel and 16swg aluminium, the latter required larger clamps though.

Since then I have made quite a few, they usually get cut up and the metal used for something else, I don't have enough metal or enough space to keep them. Most of the first folder is currently used as a hydraulic press:-)


Figure 1. One I made earlier. Well it managed that scrap of ali' OK.

Figure 2 End view of folder, showing how a bend is made.


The basic principle is a hinge. Like the Stiff records T shirt said "If It Aint Stiff It Aint Worth A Fuck", If you try to bend a couple of foot of 16 swg the folder needs to be pretty stiff. The folder I made last weekend was OK forming some small 12swg patches for a landy chassis, the longest patch was 8" long, conveniently that was the length of the folder.

I have taken a couple of photos, bear in mind this is made from scrap and fairly quickly, even so it can put neat bends in sheet quickly and accurately.

Figure 2 should have a piece of metal in it really, this illustrates the principle, just a hinge. This folder is 1/4 x 2" angle and the clamp is 1/2" x 2". The clamp piece is a bit that had been used previously as a clamp, except it had been used near vertically before, the angled face was bearing down on the sheet. If I had been able to find some tube to weld to it to mount it like that again I would of done, it wasn't stiff enough just bolted down.

A basic pan folder is the same as this except it uses loose fingers instead of the clamp strip. I did a similar thing with one of my folders the body was built with high sides and an overhead clamping beam, basically I found a clamp that was the right length and used a couple of scissor jacks to clamp it down. I am told in a "proper" pan folder the clamp looks like segments of angle iron held by a clothes peg[?] with a clamp pushing them down, well I didn't really understand either.

The place for material is probably a scrap yard. The folder body needs to be stiff enough to support the loads from the other parts, so if they are strong this needs to be. I have my eye on a piece of 10" deep rsj for the body of my next folder.

The folder part is much better if it is made from flat stock with a bit of angle bolted to it, that way you can unbolt the angle if you need a bend close to another bend and in the opposite direction, s bend.

The clamp piece needs accurately locating, if you think about radius of bend and metal thickness you can see what I mean. In Figure 1 2x6mm socket heads can be seen these are locating the clamp, the two sets of holes are for 0.083" and 0.061" sheet. You need to overbend slightly when making a bend, to get consistant bends stops are very handy. Bolting the clamping piece down rather than some sort of clamp is fine, you need to be able to get the clamp out easily when bending a channel.

My hinges are 4 pieces of thickwall tube, I just cut a 2"x1"slot in the ends of the angle and welded the tubes in. The hinge pins are some 1/2" socket heads. Each time I make one of these I make my hinges like this, the centre of the hinges should be the centre of the sheet bend radius, I haven't put the centre in the right place on this folder. It would be far better if the hinges had large diameter pins, an inch or so, and the position was adjustable so it could be located perfectly.

I should really go and look at a proper one to see how they are made, there is nothing worse than redesigning the wheel only to find they are round not octagonal.


Figure 3 Rendered view of autocad drawing, the rendering isn't getting any better. If it displays badly it's cos I didn't save it as websafe colours! I didn't bother drawing the handle and the bit that is welded on the body to hold it in a vice by.


  Cobbled together on the Friday 13th April 2001

{last modified 13 th april 2001}