Having a sheet metal bender in the workshop makes a huge array of normally difficult DIY projects, suddenly simple. It is even better if that same bending machine can also be used for bending acrylic sheet and other plastics as well. That’s why we want to share this great DIY project with you, because this thing is just so handy!
Professional workshop (or even DIY hobby) sheet metal and acrylic benders, do not usually come cheaply. This is always surprising, as they are such simple pieces of equipment with so few parts.
So, in this project, we show how we made our own quick and easy DIY sheet metal bender. Our design is suitable for the Home DIY masses, since it is made from easy to tool wooden particle board. With a bit of noise and dust in the workshop, you can have this project cut and screwed together in just an hour or two.
WHAT THE DIY BENDING TOOL CAN DO
Our DIY metal bender provides sharp and professional looking folds when used on 0.5-2mm thick sheet metal, tin and aluminum sheet. We can also use it to bend acrylic and other plastics up to a thickness of 10mm (ie: using an external heat source).
A step-by-step guide would likely be overkill for a project of this simplicity, so for this project guide, we mainly rely on photos of what we did to show how the design went together. They should be easy to decipher for most DIY readers.
In general, this is a quick and easy project with very satisfying results for those with basic DIY skills and relatively basic tools available in the work shed. The tool produced by this DIY project will be useful in the workshop for years to come.
The bender is great for making protective metal and aluminum boxes for electronic circuit boards, protective edging for furniture, component covers, etc. We have only just started to scratch the surface of the machine’s future potential ourselves.
MAIN COMPONENTS AND BUILDING
The bending tool we built basically consists of three separate main pieces.
The base board which is stationary; a second folding part of the base board, and a bolt down ‘clamp’ board that holds the sheets of material to be bent firmly in place.
GENERAL MATERIALS AND SIZING
We used 15mm thick particle board for the main base of our project. The particle board was easily rigid enough for making a machine that satisfies our relatively light duty sheet metal bending needs. We are not about to equip a heavy duty engineering plate metal workshop with this wooden DIY unit, but it still does a fantastic job! You may wish to modify material and design to make a larger, smaller, stronger or weaker machine to suits your own specific needs.
The sizes and widths of pieces and parts used for our unit were only roughly based on sizes of materials we had available in the workshop. To the most part, measurements are not at all important in the overall function or design of the bending machine. For anyone wishing to make a copy of our unit, just look at the photos and cut board sizes that look roughly in proportion to ours.
Other materials we used in this DIY project included: 2 x strong metal hinges; a strip of 20mm wide x 3mm thick aluminum strip to strengthen the bending edge on the clamp board; a handful of additional wood screws, 2 x M8 bolts, 4 x large rim washers, 2 x spring washers and 2 x M8 nuts.
BUILDING THE BENDING MACHINE
There are only a few main important points to consider in building this bending machine.
Firstly, if not using particle board as we did, at least use a strong, rigid wood or metal for the main base and folding parts. Any flex of the base or clamp boards will degrade the quality of metal bends, especially in thicker sheet materials.
We would not recommend using particle board thicknesses anything less than 15mm (and if done again from wood, we would possibly double up the 15mm board, or use a 30 mm thick particle board).
Secondly, use extremely sturdy metal hinges with little or no give in the joints (ie: backlash).
The hinges need recessing into both the base board and the folding board such that the axis of the hinge joint sits flush with the line of fold (between the base board and the folding board). A wood router or CNC machine will be a great help in cutting this recess if available, but the job can also be done manually with a little careful chisel work.
While the cutout doesn’t have to fit the hinge area exactly, it is important that the depth is at least accurate and that the folding edge between the base boards is positioned to be close and well seated. The more accurate this is, the sharper, cleaner and more precise the final bends will be.
Screw the hinges into the base board and folding board with solid screws!
A standard drill can be used to make the required bolt holes in the base board and clamping board.
When drilling the holes, use wood clamps to fix both boards tightly together in position and ensure the clamp board edge and the intended folding edge are aligned correctly before drilling through both boards at the same time. Remember to allow for the width of the aluminum strengthening strip.
Keep the holes tight around the bolts so the thread is able to grip in the wood of the base board. Glue the bolts in if necessary. We don’t want the bolts to turn or fall out through the bottom of unit when the clamping board nuts are loosened or removed from the top of the unit.
Screw or glue additional lengths of particle board to the underside of the base board (as in the photos) to allow the unit to sit flat on a table without the bolt hexagonals protruding through the bottom.
The clamping board holes then need to be drilled out to be slightly larger than the M8 bolts. This allows the clamp board to slip over the top of the bolt threads easily.
Use round drill holes in the clamp board only if your bending machine is going to be used for relatively thin sheets of metal or plastic (eg: 0.5mm to 2mm thick).
If wanting a unit which also handles thicker acrylics and plastics, use adjustable slots in the clamp board instead. The slotted holes allow us to adjust the inner folding edge away from the bending point of the base board when bending thicker acrylics and plastics.
We built a machine with the slotted hole clamp board option. The slots were made using a CNC machine.
We were impressed with what we had produced in such a short time and by the great job it did!
After the easy and professional looking folds we made in 2mm sheet metal and thicker acrylics, we immediately started thinking about a merits of a larger, heavier duty steel version for bending thicker plate steel. Keeping the same general concept of design, but by significantly increasing bend leverage and material strength all round, we are sure this general design will still work well on heavier applications.
Tip: Folding thicker aluminum sheet and acrylic (ie: >2mm thickness):
Thicker materials tend to give a rounder looking edge on bends. If you are looking for super sharp folds, go the extra distance and do the job using this professional technique.
For cleaner angles we recommend pre-slotting a channel along the line of the inner edge of your intended folds, before bending. Ideally, this can be done with a router and clamped straight edge; or a CNC machine using a V bit; or even a finely adjusted circular table saw. The slot depth should be approximately 30-50% of the depth of the total metal thickness and of similar width.
Upon folding, the channel will allow the inside of the fold to collapse in on itself more easily, bending into a neat 90 degree angle. The technique really makes a difference to the finished look.