Introduction: How to Cut & Fold Sheet Aluminium
This instructable shows how sheet aluminium may be cut using nothing but a knife and a metal straight-edge.
A simple metal-folder, suitable for making small metal boxes and chassis, is also described.
Step 1: Cutting Aluminium Sheet
Sheet aluminium can be cut without the need for a guillotine or tin-snips which tend to deform the metal.
With the aid of a straight-edge and a sharp knife "score" BOTH sides of the aluminium sheet. This weakens the aluminium and creates a "fracture line".
Place the "fracture-line" over the edge of a table and bend the overhang SLIGHTLY downwards. Flip the sheet over and repeat. After a few "wiggles" the sheet will fracture along the cut-line leaving a clean break as shown in the above photos.
With care and patience full-size sheets of aluminium can be cut using this method. Create a long fracture-line then progressively bend the sheet from one end to to the other.
Step 2: Folding Aluminium
The metal-folder is made from two right-angle sections of metal. My folder is made from aluminium but "angle-iron" is okay.
The spacing between the two nuts and bolts determines the maximum width sheet that can be bent.
Prepare your work
Mark where you want your bends.
Remove any unwanted corners.
Fold the aluminium
Now slip the aluminium sheet between the two angle-sections and tighten the nuts and bolts such that the "bend-line" is just visible at the narrow-end of the folder.
Hold the "bend-line" against the hard edge of your workbench and roll the "bender" forwards and upwards while exerting your body-weight downwards. This will result in a sharp fold.
Stop when the fold is 90 degrees.
Step 3: Corner Folds
Make a slot along one edge of your folder to accommodate the first bend.
Position the first fold such that it will enter the slot when the bend is complete.
Complete the bend.
The completed corner is shown in the last two photos.
When folding edges (see first photo) it is the edge that is placed in the bender ... not the sheet itself.