How to bend 34 inches of plywood

Bending sheet metal

Sheets are used in many areas.

  • Cladding and finishes on the house (roof, for example)
  • on the car (body and underbody)
  • numerous uses in the garden

You are not only faced with work such as sanding, stripping, cutting or painting. The sheet metal literally has to be bent into shape again and again. Like every material, sheet metal also has its special features that you should consider when bending (folding).

Sheet metal cannot be bent arbitrarily either

As with other materials, you must also maintain a maximum minimum radius with sheet metal. If you bend too far, the sheet metal will tear. How big these radii can be depends on the metal used from which the sheet was made.

  • Steel sheets: Radius a maximum of one to three times the sheet thickness
  • Aluminum sheets: 0.8 to 3 times the sheet thickness
  • Copper sheets: 0.9 to 2 times the sheet thickness
  • Brass sheets: 0.7 to 1.5 times the thickness

The specific alloy is decisive

However, you have to note that these are only very rough guidelines. Explicitly steel alloys can differ significantly in their properties, but the bending properties of other metals also depend heavily on the alloy ratios.

The rolling direction of sheet metal

In addition, the manufacturing technique of sheet metal is also important. Sheets are usually rolled. This creates a flow direction of the structure. If you want to bend in the direction of rolling, the sheet will tear much faster than with transverse bending.

Bending sheet metal without special tools

While there are various machines to choose from in industry and trade, as a do-it-yourselfer you will mainly count on your muscle strength. Nevertheless, you should definitely have a minimum set of sheet metal bending tools.

  • Vice, padded jaws
  • wider jaws for larger sheets
  • if necessary a folding bench

Measure and mark the sheet metal

When measuring the sheet metal, you must also take the correction deduction into account. This is the shortening caused by the bend. The thicker a sheet, the more important this dimension is. With very thin sheets, however, you can almost neglect it.

Step-by-step instructions for bending sheet metal

  • suitable measuring tools
  • Scriber
  • Vice, possibly with clamping jaws
  • Press brake
  • different hammers
  • Rubber mallet

1. Preparatory work

Measure your workpiece and, if necessary, cut it to the right size. Be sure to consider the proof, however.

2. Scribing sheet metal

Mark out all the important dimensions with a scriber. Make sure, however, that you always only mark on the inside of the sheet. Otherwise the sheet could tear with the cracks on the outside.

3. The bending (folding) of sheet metal

Most bending jobs will be right-angle sheet metal bends. But if you need a certain angle, you can also make a negative form, for example from hardwood.

You can proceed slightly differently when bending sheet metal for vehicles (especially in the underbody area). Most of the time you will cut out rusted sheet metal and protect everything with rust protection. You weld the sheet metal that extends over the surface on one side. You also set spot welds in front of the beads. Then use the optimal size hammers to hammer the sheet metal into shape, i.e. into the bead. Always press the sheet metal firmly against the sub-floor while welding.