can anyone tell me a formula to get the bend allowance for back to back bends and end bends on square tube. this is being bent on a hossfeld bender with a homemade die. so i would need a formula that would work off of any given radius. hope this makes sense.thanksmichael
Reply:It's really quite simple.I'm sure you're familiar with the carpenter's "inside to outside or outside to inside equal center to center measurements"In other words. You're trying to find the center to center distance measurement between two posts or uprights of the same size. You can have someone help you and you both hold you an end in the center of the two posts. Or you can hook the outside of one post and then pull to the inside of the other. That measurement will be your center to center.The same principle works on bends. Let's say you're bending one and a quarter inch tube hoops to make a sixteen foot angle iron trailer into a covered wagon.Pull your center to center measurement of your top rail. Let's say it's 77 inches. You're wanting four foot high sides. I always cut stuff a little long because I was a weldor before I was a fitter. Fitters always figure they're right. Weldor's know stuff happens when fitters think like that.96 plus 77 plus a ten inch fitter factor is something close to fifteen feet three inches per hoop. I pull off forty five inches and make a mark. Without removing the tape I pull it another seventy seven inches and make another mark.I put a mark on the entry side of the die. I align my forty five inch mark with that mark. I pull my ninety.Here's the glitch getter. I slide the piece through the die to the hundred and twenty two inch mark and align it with my entry into the die mark I used for the first bend. I pull my ninety.I now have a piece of one and quarter inch square tubing with seventy seven inch center to center set of legs. Uneven legs, but seventy seven inch center to center.Think about it.If you have two marks some distance apart. And you do the same bend starting with the marks those marks will end up being the same distance apart still. The trick is you can't make your marks and then pull one bend from one direction. And then turn your piece over and use the mark for a bend from the other direction. The marks will be the same distance apart. But the legs of bend won't.btw if you click on my signature there's a section on bending square tubing with nothing or anything. Nothing but a thing.life is good
Reply:I read that about 4 times and that makes more sense than anything i have been told about bending tubing.now if i can remember it when i need itthanks michael
Reply:Here is a website that I have found most useful.http://www.pirate4x4.com/tech/bendin_tube/index.html
发表于 2021-9-1 00:41:51