OP
wroughtn_harv
Super Member
<font color=blue>Can't see real well, but I don't see a lot of buckling on the inside of the radius. Maybe it's how you clamped it?</font color=blue>
I don't fill the tubing. It's all in the clamping.
If you ever drive by what some folks refer to as wrought or ornamental iron fencing you will see little circles about four inches or so across as decorations. The way these are made is you have a gear reduction motor attached to a drum the size of the inside diameter. In a slot in the drum you place the end of a piece of half inch square tubing. You turn on the motor. It wraps the tubing around the drum. When you've got the whole stick of tubing wrapped around the drum tight you have what appears to be a coil spring of sorts. You cut down the center length wise of the coil. You have all these circles. You tweak the ends of the circle together and you now have circles for welding in for decoration.
Small tubing bends so easy and it tries so hard to please.
Solid stock is a problem because you have the stretching on the long side and the compression of the short side working clean clear through.
If you look at a bend in solid stock where they used heat to facilitate the bend. Most folks don't stop and think for a minute. They just heat the inside of the bend causing it to fold making the bend. If they've thought a little bit they might heat the outside of the bend and let that stretch.
Neither one of those bends looks for crap. The way to do it with a torch is to heat the whole section to be bent beyond red to orange. Then you bend the piece over or around something. The bend will come out spectacular and look good too. A torch can help do a bend with pipe and or big tubing. But chances are most likely you're not going to have the area heated evenly enough not to cause more problems rather than eliminate them. Some folks bend pipe by heating it in a forge. But they fill it with dry, important, dry sand and compress it first. This supports the material from the inside as the bend is made.
On the tubing you're working against the inside not wanting to compress and the outside not wanting to stretch. So you have to give it some support. It needs your help.
That's why we clamp it so tightly so it won't slip. What happens if we don't have it clamped tight enough and it slips is the tubing fails and it kinks. But if we have it supported, with the flange in this case, we're forcing the bend to happen over an area evenly. The evenly is really important. The tighter the bend the more deformation. The outside has to stretch more and there's more compression on the inside.
I have a friend who'd made a mini Hossfield for small craft and handyman stuff. It's called the craftbender and he's here south of Dallas. He sets up in Canton every month. I haven't seen it in action yet but a year or so ago he was telling me that he'd taken what I'd show'd him and made a die for doing half and three quarter square tubing with it. He's a character, names, Rylie. He talks almost as much as me and gets just about as excited about making things.
BTW I have two of his craftbenders. I use them to do all kinds of trick things. I guess since I use them so much I should give Rylie a call and have him get with Mohammed and the two of them find a way to get ya'll the opportunity to see and purchase one.
Maybe the best way to explain the way the bending works is to examine the emt bender you can buy for little or less at your local box home improvement store. Emt is a thin wall stiff walled round tubing. If you try to bend if over your knee it's gonna kink and break. If you try to wrap it around something like a piece of pipe. It's gonna kink and break.
But you put it into that simple little bender and with a little practice you'll lose all respect for electricians. It ain't that hard. (joke guys, joke) But the reason it works is the emt is forced around the die and the sides are supported while doing so.
I'm running late. I wish I had time to answer all the questions. I'll try to do better. Bgott, I can't thank you enough for your input on some other topics. Even though I haven't replied I do want to publicly acknowledge your input is appreciated.
I don't fill the tubing. It's all in the clamping.
If you ever drive by what some folks refer to as wrought or ornamental iron fencing you will see little circles about four inches or so across as decorations. The way these are made is you have a gear reduction motor attached to a drum the size of the inside diameter. In a slot in the drum you place the end of a piece of half inch square tubing. You turn on the motor. It wraps the tubing around the drum. When you've got the whole stick of tubing wrapped around the drum tight you have what appears to be a coil spring of sorts. You cut down the center length wise of the coil. You have all these circles. You tweak the ends of the circle together and you now have circles for welding in for decoration.
Small tubing bends so easy and it tries so hard to please.
Solid stock is a problem because you have the stretching on the long side and the compression of the short side working clean clear through.
If you look at a bend in solid stock where they used heat to facilitate the bend. Most folks don't stop and think for a minute. They just heat the inside of the bend causing it to fold making the bend. If they've thought a little bit they might heat the outside of the bend and let that stretch.
Neither one of those bends looks for crap. The way to do it with a torch is to heat the whole section to be bent beyond red to orange. Then you bend the piece over or around something. The bend will come out spectacular and look good too. A torch can help do a bend with pipe and or big tubing. But chances are most likely you're not going to have the area heated evenly enough not to cause more problems rather than eliminate them. Some folks bend pipe by heating it in a forge. But they fill it with dry, important, dry sand and compress it first. This supports the material from the inside as the bend is made.
On the tubing you're working against the inside not wanting to compress and the outside not wanting to stretch. So you have to give it some support. It needs your help.
That's why we clamp it so tightly so it won't slip. What happens if we don't have it clamped tight enough and it slips is the tubing fails and it kinks. But if we have it supported, with the flange in this case, we're forcing the bend to happen over an area evenly. The evenly is really important. The tighter the bend the more deformation. The outside has to stretch more and there's more compression on the inside.
I have a friend who'd made a mini Hossfield for small craft and handyman stuff. It's called the craftbender and he's here south of Dallas. He sets up in Canton every month. I haven't seen it in action yet but a year or so ago he was telling me that he'd taken what I'd show'd him and made a die for doing half and three quarter square tubing with it. He's a character, names, Rylie. He talks almost as much as me and gets just about as excited about making things.
BTW I have two of his craftbenders. I use them to do all kinds of trick things. I guess since I use them so much I should give Rylie a call and have him get with Mohammed and the two of them find a way to get ya'll the opportunity to see and purchase one.
Maybe the best way to explain the way the bending works is to examine the emt bender you can buy for little or less at your local box home improvement store. Emt is a thin wall stiff walled round tubing. If you try to bend if over your knee it's gonna kink and break. If you try to wrap it around something like a piece of pipe. It's gonna kink and break.
But you put it into that simple little bender and with a little practice you'll lose all respect for electricians. It ain't that hard. (joke guys, joke) But the reason it works is the emt is forced around the die and the sides are supported while doing so.
I'm running late. I wish I had time to answer all the questions. I'll try to do better. Bgott, I can't thank you enough for your input on some other topics. Even though I haven't replied I do want to publicly acknowledge your input is appreciated.
