Post By TDegenhart
Post By feets
Need help bending small rods
I need to build a small jig to make two 90* bends in some small 3/16" rods. The material is cheapie weld rods from Home Depot. This is part of a small finger operated toggle a friend sells. He's always bent them over a vice with a hammer. Getting the angles correct has been a hit-n-miss kind of thing. High precision isn't required (obviously) but it needs to stay within a few degrees.
His order volume is up and naturally time is short. Getting the bends right is by far the most time consuming part of the job.
This is just a little side job meant to provide him with a little fun money.
I haven't built a fixture like this before so I thought I'd call on the all knowing collective for some advice.
The idea going through my feeble mind is to take a 6" long piece of 1-3/4" x 2" scrap steel and square it up. Next, I'd cut a step 3/4" tall and 1/4" deep across the bottom so the fixture would sit securely in his bench vice. Then, I'd drop 4 holes in it deep enough to make the first bend (farthest away in the pic). Between those holes would be slots long enough to drop in the first bend. They would be deep enough to position the rod for the second bend.
I could then use a 6" piece of 3/4" x 4" steel to close over the top of the base and provide the bending force. Since it will be a hand operated device a suitable lever could be attached to the top.
The idea is to drop in 4 pieces of rod and make the first bend. Lift the pieces out, turn the short end to the side, and drop them in the slots for the second bend.
It seems easy but I'm not sure about a hinge point for the upper half of the press. I thought it'd be a good idea to have the top swing in an arc to push the parts down instead of a hinge across the back.
I imagine I'll have to play with the lower block to make sure the bends come out at 90 degrees. If the pieces spring back too far I could deck the block at an angle to provide a few more degrees of travel.
I planned on having shallow troughs cut in the top and bottom pieces to help guide the pieces in a straight line.
The work would be done on my Gorton 0-16a.
I'm probably over thinking this. What do you guys suggest?
I sell Mercedes parts for a living but I enjoy playing with metal in my home shop.
I think you are off to good start, however I'll tell you how I would do it. I fly r/c helicopters and am frequently making pieces like the one in the photo I use as linkages between servos and whatever is being controlled. First off lets name the parts of your wire so you know what part of it I am speaking of. Start at the top of the photo: end 1 then section (sec.) 1, bend 1, sec. 2 , bend 2,. sec.3 then the end okay so far? The first part of your jig is good; place the wire in it bend it over 90 deg.. Then instead of another hole in your block place a dowel pin the length of section 2 from the hole and bend the final section 3 around that. You can use a ball mill to create a shallow trough for the wire to lay in that way you know your product is the right shape, although you could use just a line between bend points. Aslo due the math first example : if make a trough then hole 1 will need to be longer = the depth of the trough, as well as the offset of the pin determined by the dia. of said pin so the length os sec. 2 will be correct.
I did one of several things : confused the bloom'in ^ell out you, made simple task extremely complicated (now waiting for my engineering degree to arrive in the post), or possibly helped. I hope the latter if not it will give some folks ammo.
you could get those for a penny from someone with a little robomac
After watching a wire bending machine pound far more complicated shapes than these out at a trade show, I'd suggest that a few phone calls be made, and like as not you can buy a box full for a tiny markup over the price per pound of the raw material.
Other than that, do a google images search fro "Wire Bender".
Wire bending jig was one page that came up in that search for me.
It can be as simple or as complicated as you want it to be, but dropping $50 or whatever the quote comes in at, on a crate full to keep you going for a year or so, seems the cheap method.
For benders, look for a Mexican made version fueled by ethanol with a penchant for cigars and floosies.
Originally Posted by feets
One of these would seem to be the ticket: Vise-Mounted Wire Bender
Rex, That (micro-mark tools) is a cool website. I also so little 4 inch by 4 inch benders and a mini press brake, and came upon this, which might have a few more features:
Originally Posted by bjorn toulouse
If you want to automate this a die that advances the wire and shears the wire and bends the wire would be one way to do this. (not necessary in this order)
Simple mater of what you want to spend and how fast you want them done.
Thanks for the input.
He makes these in batches of about 50 at a time. In a little over a year he's sold just over 200 of these. Some are made with bend #2 in the opposite direction.
If I built something like Peter S made:
The fixed blocks could be made with a cut deep enough to act as a wire stop to fix the distance. A bridge (for lack of a better term) could be placed on top of the blocks to slide the wire in for bend #2. That bridge could serve to hold the piece vertically as well as set the depth.
Both bends could be made on the same setup. That should also allow for bend #2 to be made in the opposite direction for the occasional left handed piece.
Does that sound a little more down to earth?
That's a Manuel Bender, the op is looking for something a little more automated.
Originally Posted by Hightemp
This is slightly overkill, but if you can find a Diacro #1 bender...that would be the ticket.
Pretty much a very solid, universal bender with little need for dedicated tooling.
They're on ebay but pretty pricey.
I got mine at a local auction for less than $100 and use it quite alot for jobs like yours.
Ideal for a four slide.
I have a duomite, works great for jobs like this: OGI Duo-Mite
There's knock-off available too, but I have the made in USA version.
But I agree a custom-made jig would be probably be faster.
On edit, the link bosley posted is the knock-off of the duo mite. It looks exactly the same.
Last edited by Sea Farmer; 07-15-2012 at 02:42 PM.
Reason: added info
The comments about buying them is realy the way to go. Especially as the bends are in diffrent planes. Makes it fiddly + time consuming. A spring or clip bending company's prices will be dirt cheep. So cheep its probably best to get a thousand or so of each hand done. I leant - lost my ass a long time ago on a similar simple bit. You can't beat buying wire on mass on the coil and the automation to make the bit in next to no time.
Making say 5 or 10 yep, hand works the way to go, at a quantity of a few hundred a year there's better more profitable things to do!
Thanks for the input.
Not only are there right and left handed versions but there are also some versions that require a longer section. Those can be either right or left handed as well.
Now we're talking about doing a similar job to fit a similar application. That would add a few more pieces to lay out. Since the orders some in one at a time it would be nice to be able to walk out to the garage, knock one out, and have it ready to ship (assuming he doesn't have a finished piece available). The vast majority of these are of one design so it's easy to keep a few on hand.
Again, this is a good excuse for me to play with my machines and get a little practice building stuff.
I started putting something together last night. It's based on Peter S's device I referenced earlier. The base is a 5" wide plate 1/2" thick. An old bar of 2" x 1-1/4" A2 gave it's life for the handle. A sloppy handle pivot was a concern. Since I was building this out of stuff I had laying around, the search was on for something to make a tight fit.
I dug up an old lug stud removed from my 65 Plymouth. I drilled and tapped the base plate to match the lug and popped a 1/2" hole in the handle. To keep the fit tight, I turned the shank on the lug stud until it was a good fit in the handle. Two flats were ground on the head of the stud so i could turn it with a wrench. I thinned the handle until the lug shank bottomed against the plate but did not pinch the handle. The last step was trimming the stud unti it was flush with the plate.
The result of all this work is pretty nice. The handle turns smoothly with no slop and no binding. A little red Loctite on the stud threads and a touch of lube on the shank made it a perfect fit.
Tonight, I'll make the top part of the handle and put together a block to hold the wire. After that, I can play with it to see how accurate the bends are. If it's good, I'll build an adjustable stop for each side of the handle travel, a lug to hold it in the vise, and do a little cosmetic cleanup.
Keep in mind that my skills are rudimentary at best and I have only the bare minimum (if that much) for tooling. The more I work with it the better my work becomes. It's been fun messing with it so far.
I finally found the time to finish the contraption. Its insanely overbuilt for bending small rods but was made from junk I had laying around. What was a 3 to 4 minute operation with a hammer and vise is now takes 7 seconds. It may not be pretty but it works great.
I needed a little practice building stuff to specific measurements instead of just hacking metal until it looks like it'll fit.
I brought it to work today so my friend could swing by and pick it up at lunch. This was a pretty good test for the device. It's fairly robust. A bunch of my techs have been playing with it but none of them have broken it yet.