Bending flat bar

Tell us what you want to bend and how involved you want to get.

That "brief description" is about as misleading as it can be, I think. You could probably bend 1/8" thick alumimum about one inch wide with that plywood "circle", but you'd have a heck of a time doing it with steel.

I see only two pieces of equipment: the chop saw (which has a small vise attached to its base) and the plywood "circle". So I can't comment on "the piece of equipment attached to the bench.

It looks like the guy in the picture has made a an "S" scroll. He didn't make it on that setup. Maybe he used the "circle" to get started, but he had to do a lot of it freehand.

That chop saw with that blade is a pretty stiff investment if you only want to bend a couple of things. I'd just get a hardware store hacksaw.

It looks as though the piece of metal in the chop saw picture is thicker than the piece that the guy is shown bending in that jig.

If you really want to learn more about bending metal, google "hossfeld bender" or take this link to get started:

Pete Stanaitis

snipped-for-privacy@gmail.com wrote:

Thanks for the reply.

I'd like to bend 2.5mm x 25mm flat steel bar "the easy way", in a semicircle with a radius of approximately 150mm. I only need to bend two pieces. My budget is extremely limited. We are talking USD50 or less, so unfortunately a Hossfeld bender is not an option. I know that for anything serious, buying the right equipment is the way to go, but this is purely a one off hobby project, where the goal is to learn a little bit along the way, and there are no time constraints.

Before I started searching the web, I wondered whether I could simply bend the bar by forming it around something hard of the correct radius, like a pipe, with a mallet. The radius and shape of the bend doesn't need to be balls on accurate.. it is only be a matter of aesthetics. What kind of results could I realistically expect with this approach?

Bruce

Bruce,

That should work fine.

It will go a bit easier and not have as much 'spring back' if you heat the steel with a propane torch (the ubiquitous "Bernz-O-Matic") and then bend around your mandrel (the piece of pipe), but cold bending a couple of pieces should be no problem.

Carla "Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming

-- WOW--What a Ride!"

The plywood circle is easy, use two pins or a slot to anchor the end, leaving the starting end a bit long then trimming with a hacksaw. Just about anything round and solid can give a decent curve. Pipes, pots, gas cylinders, telephone poles, look around use your imagination. For angle bends in flat stock I often use an old monkey wrench like this,

at garage sales and swap meets. I have a 24 inch model I have used to bend up to 2 x 3/4 bar stock with a little help from a torch and vise.

What do you have for tools already? If you're only making two pieces you could use a simple buck and heat to for the steel.

First get some plywood and cut out the shape you want the steel to finish in. If needed layer a few pieces to make it thick enough.

Now make a stop on one side out of the same stuff. You want it thick enough to hold the steel tight.

Now you need HEAT, torch will work, all you need is enough to heat a section to red. Then you heat and form the first section, Then repeat until you get it to a close fit. Once you get it formed use a rawhide or dead blow mallet to finish it. Just do it the same way a blacksmith would have done it.

Yes there are tools that can do this easily, but you really don't need them. Consider that using the same type method is how some of the high dollar hand built vehicles are made. Shot bags and wood bucks.

Bruce

There are circle rollers that cold roll flat bar. But they're not made of wood. You can heat steel with a torch to red hot and bend it around wood although it will char the wood. Barrel hoops used to be fitted hot to the barrel staves this way. Once they cooled they shrank and the barrel was liquid tight.

V

If you don't need accuracy you could bend the center of a longer strip around a ~125mm tree trunk. It will be easier to overbend it and then decrease the radius to fit a cardboard template since you can place the curve open-side-down on a piece of wood and hammer the center. The results will depend on how careful and persistent you are.

Jim Wilkins

Making do, a big vice firmly mounted to a bench so it won't move, and a solid cylinder of required diameter (maybe an old starter motor) can be employed. Trap your bar between the back vice jaw and cylinder, and pull back on it. Can do over 90 degree bends on up to 1/4 inch x 1 inch mild steel quite easily. Jordan

Okay, bruce. If you DO want to buy a tool, get the Harbor Frieght bench mounted Hossfeld "look-alike" which is on sale for as little as 49.95 or so from time to time. If you want to do it with absolute minimum tooling, do this: Find something hard and relatively flat. Lay two pieces of something hard, flat, about 1/4" thick, and smaller than the above on top of it, about 2 inches apart. Cut your workpiece a couple of inches longer than the final arc needs to be, since this process won't bend all the way to the ends. Lay your work piece on top of the two pieces so it bridges the two pieces. While holding on to the workpiece so it doesn't fly around or hit you in the face, hit in between the two pieces with a hammer. The metal will bend there. Practice this first with light blows until you get the feel of the process. Start this process close to one end of the workpiece. After you get the first bend, advance the work piece just a little, let's say 1/2", and strike again. You will now see some more bending going on. Keep doing this, while checking your radius against a circle of the correct radius that you have scribed onto a piece of anything. You may find that you can advance the workpiece more that 1/2" at a time and still maintain a decent curvature. Continue bending and checking until you have made no more than 1/4th of a circle, a little less is better than a little more. Now start the same thing from the other end. If you get to a point where the tail end of the workpiece is in the way of the hammmer, bend the workpiece sideways a little; you can straithen it back later. This probably won't be a problem since you are only making a semi-circle. You can probably see that, if you overbend, you can turn the workpiece over, so the hump is UP, and hit down to undo some overdone or misdirected blows. Since you are new to this, I suggest that you don't use heat, and for this material, I don't think it's necessary. The other posters that mention heating are, of course, correct in doing so, but since you say you new to metalworking, the heat adds a dimension of complexity that you may not need right now. This simple method works very well and has been used ever since the first metalsmith went beyond jewelry. We (blacksmiths) often use this same process (with heat) to bend things the hard way. A typical use is to bend 1/4" X 1" or so to form a perfect ring, forge welding the ends together when we are done bending. Farriers who make their own horse shoes, may use this process every time.

If this explanation isn't clear enough, email me off list.

Now, if you get into this and LIKE it, let us know. We can connect you with a blacksmithing organization almost anywhere in the world where you can get training and support. (Yes, even if you DO use metric linear measurements!)

Pete Stanaitis

------------- snipped-for-privacy@gmail.com wrote:

Pete Do you or some one you know have a Hossfeld #2 with the hydraulic option Hossfeld offers? I just bought a #2 and in order to use it in the shop without the long handle and bolting it to the floor. I would like to hook it up to my press brake hydraulics. What I need are some photos and measurements of the stroke and bore of the cylinder and the ratcheting mechanism they use to advance the cylinder after a bend. I also have been planning on adding a propane forge to my shop and would appreciate any advise you can give in that regard too. I did get my coal forge going after rebuilding the blower this fall but it is too big and dirty to have in the shop and too cold to run outside.

Steve in MN

My HF bender is on a small wheeled table with pieces of 1" pipe welded around the table top. I put a 4' piece of 3/4" pipe in the appropriate holes and pull the bender handle toward it, like squeezing big tongs shut. As a side benefit I can roll the table around to let long pieces clear nearby cabinets so it doesn't need as much open floor space to use.

It's really more complicated, but you should get the idea. The tabletop is on trunnions and flips over. One side has a heavy corner notcher permanently attached, the other is for the bender or an 8" shear. All three use the pipe handle for counteracting leverage. The trunnions are bolts which I don't tighten very much, so a heavy unbalanced downward pull will make them slip rather than toppling the whole table. The base is a wooden cabinet for the bender dies and other light metal bending stuff.

Jim Wilkins

Wow, thank you all very much for the suggestions, what a helpful bunch of people! I am leaning towards spaco's method, because I don't have access to a torch, and I can't find anything lying about with the correct radius. Your explanation was good, I understood you. Something like a makeshift brake where your hard flat 1/4" material is the die, your hammer is the punch, and you make many small bends to form the curve. I will report back with the results.

Bruce.

I'll assume you don't have machine table with "T" slots.

Bar this size bends easily, go to the lumber store and get a 2x6 and a

1" hardwood dowel.

Saw a foot off the 2by (or not, if you don't have a bench to screw to, or large vise to hold something) and drill holes for dowels leaving a

1/4" to 1/2" space between the dowels (drill the dowel holes as parallel as you can).

Bind the flat by placing between the dowels and pull, move the flat forward a bit and do it again, etc. Gently hold the bar against the 2by while pulling.

If you brake this way almost any curve could be made and compared to a simple compass curve (drawn somewhere), or generated (by any means).

After a couple of bends are made, mark the jig, you'll quickly figure it out.

When you are done, screw the jig to a wall somewhere so people can hang stuff from it (:-) .

Matt

snipped-for-privacy@gmail.com wrote:

Hi, Steve. I don't have the hydraulic setup for my #2 either. I know several guys who have #1's and #2's, but nobody that has the hydraulic unit. Four of us went down to Hossfeld in Winona some years ago and had a half-day demo. It was great! They had the hydraulic attachment on their machine, of course, and they really knew how to use it. I don't blame you for wanting to have one. But, it is sorta slow. Not that the cylinder is slow, but it only pushes so far at a time. You have to reset that link mechanism in the rear (see link, below) to get a full "pull". It's not a BIG deal to reset the link, but it does take time. You can probably get a lot of the detail you need just from the picture. You NEED to have a small diameter cylinder to get it to move fast. Don't need a lot of power, because all you are doing is to push as hard as one strong guy could pull on the long bar anyway.

Take this link to see a pretty good picture of the hydraulic setup:

You can also contact them and buy a parts manual for the thing. I don't remember whether its the same parts/accessories manual that has all the other dies in it. They also have a really neat "how to" booklet for setting up to bend almost anything. Anybody who has a Hossfeld or Hossfeld knock-off should have both of those books. The pictures and instruction are really valuable. And, you can elect to buy any parts for the hydraulic setup that you don't want to make. (Not cheap, though).

I really don't have enough room for my #2 in my crowded shop either. (See

So I sank anchor bolts into the floor in the middle of the garage for it. I bolt it down when I need it, then, when I remove it, I screw headless set screws into the holes so they won't fill with crud.

Hope this helps, Pete Stanaitis

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Up North wrote:

Thanks Pete I enjoyed looking at your shop. I see you have the same lathe and welding helmet I do and the same amount of open floor space. Is that a Little Giant hammer you have there. I have been looking at the tire hammer designs that look similar in design to the Little Giant. Have you had any dealings with these home brewed machines? Steve

Yes, that is a Mayer Bros. Little Giant, 50 pound hammer. You can see my little collection of them at:

Our blacksmith club, the Guild of Metalsmiths recently completed a "build" of, I think, 22 of those "Clay Spencer" Tire hammers. The guys are quite happy with them. The club built one extra hammer at that time and auctioned it off for well over $2000, BTW. I'd have gotten into that build, but, as you can see, I really don't NEED any more trip hammers.

Pete Stanaitis

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