A few years ago I offered to build my brother in law a fancy steel bracket, custom shaped for a vintage industrial paper-cutter he'd just bought (haven't we all been there). I drew a fancy CAD model, got myself all pumped up to make this awesome overkill steel support, but then reality set in: I don't work with steel, my toolbox is only stocked for woodworking. What to do?
Well this is what I came up with. It worked for me, gave me accurate bends, it didn't involve investing in heavy tools or building a reinforced workbench, it's dirt cheap and it's dead simple to create. I hope you like it!
By the way, this is my first instructible and I'm creating it as a submission for the "Build a tool" contest. It is definitely not the fanciest submission, but I think it's a high quality DIY tool and a solid solution to a real problem. If you dig this, I'd really appreciate a vote, thanks!
Step 1: Tools You Will Need
1: A length of lumber (not pictured)
This tool was created using a five foot long 2x8. The heavier the steel, the longer you'll want this to be, but practically speaking if you're alone in your backyard, a six foot board is about as long as you can take full advantage of anyway (By the way, I have no idea how lumber is sized in metric countries, here in the US, standard board dimensions are given in inches + 1/2 inch. So a "2x8" means a board that is 1.5 inches by 7.5 inches. Makes perfect sense, right?). Also, in a perfect world this board should be as thick as the crease you're creating is long. For example: In the case of my project, the bend I was creating was 1.5 inches long (measured along the crease), so a standard 2x4 was sufficiently "thick." If you wanted to create a longer crease, you could use the same board and simply 'shuffle' the piece through the 'brake' as you worked, but a thicker piece of wood would be more convenient. I'll make the measurements I'm talking about very clear soon.
2: A mallet or sledge or fixed vice
I stated at the outset that this was a solution for the workbench-less, and it is. I did this job with a rubber mallet and no bench. But if you happen to have one, this tool could be very complimentary to a vice. As with the lumber, the heavier the steel you want to bend, the heavier the mallet or sledge you'll want to use.
3: A wood-cutting saw
Almost any will do.
4: A strong clamp
I used a standard, old-fashioned, metal screw clamp. It doesn't have to be any particular size, if fact you can see in the picture at the start of this instructable that since mine wasn't large enough to span my 2x8, I just notched out the wood until it fit. Any strong, metal clamp should do.
5: (Semi-optional) A pair of vice grips or two
These are used to help give your crease definition, as you'll see below. They aren't necessary in order to bend the steel, but they help you control specifically how the bend is shaped if you are doing a project where that matters, as I was.
6: (Semi-optional) A method of cutting your steel OR scraps of steel which can span the thickness of your lumber
This goes hand in hand with the vice grips. The cutting device is just to create steel scraps, and the scraps are there to be held by your vice grips and C-clamp. They are there to provide definition and specificity to your crease. Highly recommended, not absolutely necessary.
Step 2: Define Your Goals
I'm not here to dictate your workflow, but this is the step where you determine the dimensions of the piece you are going to create. For me, since I have no artistic talent at all, that means creating a CAD drawing.
I started by creating a model of the paper cutter I was modifying (or at least the portion of the cutter my piece would end up attaching to). I really enjoy CAD modeling and I can work on this part while my daughter is asleep, so I went a little overboard here. Then, I modeled the piece that I wanted to create and got all my dimensions straight. As a final triple check, I hacked a piece of scrap wood to match the rough interior dimensions of the final piece. I included a photo of that block with the (almost) finished product measured up against it here (spoiler alert).
By the way, please note "Measurement A" (top-right) in my 'technical drawing' above.
Step 3: Assembly Time! Assembly Step 1: Cut Your Board
So, before we get any further, let me be clear: I am not an animator, I just learned to do these doodles for this instructable. I'm super proud of them, but if my little .gifs drive you crazy, my apologies. I figured they'd be useful in making the steps clear. I put two photos of the completed build atop this step for reference and I'll add stills along the way if that works better for you. Onward then.
Cut a slot down the center of your lumber deep enough to place your crease at the end of the board.
In the previous step I identified the measurement you should use as "Measurement A." You don't want to widen this cut, the steel should have a tight (Like need a mallet to pound the steel into its slot tight) fit in the board, so just take your wood-cutting saw and make one nice deep cut.
Step 4: Assembly Step 2: Insert Your Steel
Nothing to it. Just shove your steel plate into the slice you just created. It will be tight, by design. You may need to take your mallet and force it in. The important thing is to make sure that the intended point of the crease is lined up with the end of the board. There's no harm in pulling it out again to get it right. The slot may loosen with several attempts but that won't hurt the final build.
Step 5: Assembly Step 3: Place the First of Your Steel 'guides'
This is any old piece of steel that is at least as long on one side as your board is thick. It also has to be small enough down the other dimensions to fit into your saw-slice. For me, this was a cutoff from the piece I was shaping. This will be a really tight fit, but that little bit of give is part of the beauty of working with wood. Just pound it in the same slot your piece being shaped is occupying, on the side of the work piece that is being bent toward, flush with the edge of the board.
Step 6: Assembly Step 4: Place Your Second Steel 'Guide'
Here, you want to take a second piece of scrap steel, again at least as long down one dimension as your crease, and secure it with vice grips to your work piece. You will want this piece of scrap to be touching the first piece and as tightly secured as possible. If it is large enough, try to get two vice grips on it. The point of all this scrap steel is to give the work piece a "weak spot" right at the crease and encourage it to bend tightly and predictably. The more reinforcing you can do, the better.
Step 7: Assembly Step 5: Apply Your Clamp
One last piece of reinforcing. Once you've taken all the steps above, in all likelyhood the weakest link in your build will be the piece of wood itself. That's where this clamp comes in. Just clamp the board as pictured and squeeze tight. All you need to do is stop the wood from splitting at the end.
Step 8: Time to Bend!
Here's the real fun part. If you felt any stress putting this brake together (and I sincerely hope you didn't), now's your chance to let it out. Again, I'm not going to dictate your workflow, I don't know how you're choosing to measure your progress, with a tape measure, a protractor or a mockup of the desired shape like I used, but my process here was to rest the board on edge with the end hanging off a curb, stand or kneel on the top of it to stabilize it, and take a few sharp swings at the piece with my mallet. The more you reinforced it with steel in the previous steps, the more freedom you have to swing wide and use the length of the piece as leverage to your advantage. The less reinforced it is, the closer to the end of the board you'll want to strike it in order to keep your crease tight. Then, I'd loosen the clamp, pull out the piece, measure, reinsert, reclamp and resume. One advantage to this design is that even though the wood will get a little 'broken in' with use, the clamp easily tightens the groove back up so the tool can be reused many times over.
If you happen to have a workbench and vice, then building everything as described and then placing the other end of your work piece in the vice would be a great way to gain a ton of leverage and likely allow you to bend your piece at will, making for some really easy shaping. I think it would end up being an even better use of this tool, lucky you!
Again, I'm no artist (though I had a lot of fun doing this animation!), tried my best to do justice to the feeling of swinging a sledge hard at a piece of steel, but you'll have to try it for yourself. I attached some photos of my finished piece here, as well as one of the piece when it was in-progress.
I hope I've done a clear job of explaining my build. Feel free to drop any questions in the comments and I really hope this inspires someone or does some good.
Thanks for reading and happy making!