How to Build a Sheet Metal Press

Cover your work bench in a smooth working surface, such as medium density fiberboard (MDF). You're going to want a smooth, level working surface onto which you will lay your sheet metal.

Fasten a 4-foot length of piano hinge to the face of your workbench, hinge side up. Make sure the top of the hinge is perfectly level with the top of your workbench, then install the piano hinge screws.

Cut an 8-foot piece of angle-iron in half with a hacksaw or cut-off wheel. Larger angle-iron is preferable. You want flanges that are 2-inches or larger. Clean up any sharp edges with a metal file.

With a 3/8-inch metal-cutting drill bit -- preferably in your drill press -- drill 2 holes 1-inch from each end of one of your angle-iron sections, spaced 1-inch apart. On the other length of angle-iron, drill holes in the same configuration, 1-foot in from the ends.

Cut sheet metal shims 2 inches wide by the width of your angle-iron flanges (one side of the L-shape.) Cut six shims.

Lay the angle iron with the holes nearest the ends, hole-side down on the edge of your bench with the vertical angle aligned perfectly to the edge. Now, lift each end and place a stack of three shims under the end where the holes are located.

Drill through the shims and all the way through your workbench counter top.

Bolt the piece to your bench-top with the face perfectly aligned to the face of the workbench. It should be a bridge with the shims creating an abutment on each end, lifting the angle high enough to pass sheet metal beneath it.

Clamp your second piece of angle to the face of your first, using two C-clamps. The two, non-drilled faces should be clamped face-to-face.

Rotate the piano hinge up to the clamped angle-iron and mark the holes from beneath with a permanent marker.

Drill the holes with a metal-cutting drill the same diameter as the widest threads of your piano hinge screws. You don't need to drill every hole as the piano hinge was designed for wood, not metal. You can drill every second or third hole, making sure you drill the holes at each end.

Bolt the piano hinge to the second piece of angle-iron. You will need machine screws the same diameter as your piano hinge screws. Get tapered heads to fit into the counter-sunk hinge. Use matching nuts and washers. Tighten the nuts snugly, but not over-tight with a wrench

Add a handle to the functional portion of your press brake. Cut a 2-foot section of angle-iron -- lighter duty, if you want. Cut a couple of 3-inch sections of angle-iron. Drill and through-bolt the short sections perpendicularly to the ends of the 2-foot section to form your handle. Lay the handle-ends over the two unused holes which are 2-feet apart on your metal press. Mark and drill the holes, then through-bolt your handle to the backside of the press. You can now slide sheet metal through the press, with the hinge down, align it, then raise the handle, to create a straight, precision bend.