Nice video. Another easier way to get the "bend" is to layer painter's tape in progressively longer piece. shortest as the first layer in the middle. Can get the bend you need without getting excessive.
Just saw your TH-cam on making and using steels. Love the idea and ashamed I didn’t think of it sooner. I have one question that I think your experience will help me greatly on; what wall thickness of steel did you use? I don’t work with steel and have no idea where to start. Great video, thanks for sharing!
Looks like this will put more pressure in the very center and then a length without much force and then some bit of pressure at the edges. Wouldn't it be better to make a sweeping bend, instead of a "v" shape? Or am I overthinking it?
does it really have to be that tight? I've never done this kind of glue up before but i have some rigid laying around and was going to use them as cauls but holy moly the downward pressure needed to bend the ones i got (industrial leftover from electrical work at a water plant) is crazy. If you need a 3 ton press to bend it, doesnt that mean that they are fine if used under 15"? I always assumed the "jointing" pressure was what was needed and the cauls were there so the overwhelming jointing pressure didnt cause the piece to concave. Im surprised this kind of pressure using clamps didnt mar up the piece :O
A better way to get a curve instead of the “v” is cut a curve in the middle of your wood and place your pipe between both pieces of wood and clamp together. That way there is no pressure point to crease the curve.
I made a set out of clamps using heavy angle iron. I used these for removing the warp in a a wide sheet of wood made from three planks glued together. Angle iron is not very flexible so tends to stay flat acros the whole length. So which is better and why?
The ideal curve for the cauls would be a parabola. When a parabolic beam is under enough center load to straighten it, it will exert a uniform pressure along its length. Luckily, the inverse is true as well: to make a straight caul parabolic, you only need to support it at the sides, then give it a center load. I.e. just make the curve by supporting the ends of the caul and apply pressure in the dead center. The curve will then be a parabola. Caveat: What I don't understand is why using the cauls won't just bend them back. To permanently deform steel you need to exceed its yield strength. When you use the cauls you would have to use the same amount of force to straighten them again, which would also exceed the yield strength, deforming them back to straight
I don't know if you've ever been metal, such as a piece of rebar. But if you want to bend it 90° you have to bend it to about 105° and then let it bounce back. Same principle applies here. He's putting a more aggressive Arc on it during the bend and the metal will bounce back to a less aggressive Arc. The pressure that's put on the steel to straighten it out is within the bounce back threshold of steel
I like the idea; for a larger set you could use either the half height or full size unistrut the bending would be a trick but it is doable. Thanks for the idea not it's off to the shop.
why all the holes? is that for improving the flexibility of the steel? you make me think about things that is for sure, also you could make a cradle to hold the cauls so you can load your glue up directly to the bottom cauls, and i was thinking how I could add threads and bolts to the ends of the cauls to assist line up and improve the clamping pressure too with least amount of clamps and hardware. It's got great potential so well done 😀👍👍
Nice video. Another easier way to get the "bend" is to layer painter's tape in progressively longer piece. shortest as the first layer in the middle. Can get the bend you need without getting excessive.
Thank you for your videos, you are one of my favorites to watch. I always get great content
Brilliant, Rob! Fantastic idea!!! 😃
I'm definitely going to make some!
Stay safe there with your family! 🖖😊
Just saw your TH-cam on making and using steels. Love the idea and ashamed I didn’t think of it sooner.
I have one question that I think your experience will help me greatly on; what wall thickness of steel did you use?
I don’t work with steel and have no idea where to start.
Great video, thanks for sharing!
Looks like this will put more pressure in the very center and then a length without much force and then some bit of pressure at the edges. Wouldn't it be better to make a sweeping bend, instead of a "v" shape?
Or am I overthinking it?
sweeping bends are much more difficult. though somewhat preffered
Damn. Don't know why the hell I never thought of that. Great idea.
great I like that idea.
does it really have to be that tight? I've never done this kind of glue up before but i have some rigid laying around and was going to use them as cauls but holy moly the downward pressure needed to bend the ones i got (industrial leftover from electrical work at a water plant) is crazy. If you need a 3 ton press to bend it, doesnt that mean that they are fine if used under 15"? I always assumed the "jointing" pressure was what was needed and the cauls were there so the overwhelming jointing pressure didnt cause the piece to concave. Im surprised this kind of pressure using clamps didnt mar up the piece :O
A better way to get a curve instead of the “v” is cut a curve in the middle of your wood and place your pipe between both pieces of wood and clamp together. That way there is no pressure point to crease the curve.
This is a marvelous idea. Plasti-dip might work better than wax
I made a set out of clamps using heavy angle iron. I used these for removing the warp in a a wide sheet of wood made from three planks glued together. Angle iron is not very flexible so tends to stay flat acros the whole length. So which is better and why?
The ideal curve for the cauls would be a parabola. When a parabolic beam is under enough center load to straighten it, it will exert a uniform pressure along its length. Luckily, the inverse is true as well: to make a straight caul parabolic, you only need to support it at the sides, then give it a center load. I.e. just make the curve by supporting the ends of the caul and apply pressure in the dead center. The curve will then be a parabola.
Caveat: What I don't understand is why using the cauls won't just bend them back. To permanently deform steel you need to exceed its yield strength. When you use the cauls you would have to use the same amount of force to straighten them again, which would also exceed the yield strength, deforming them back to straight
I don't know if you've ever been metal, such as a piece of rebar. But if you want to bend it 90° you have to bend it to about 105° and then let it bounce back. Same principle applies here. He's putting a more aggressive Arc on it during the bend and the metal will bounce back to a less aggressive Arc. The pressure that's put on the steel to straighten it out is within the bounce back threshold of steel
Love your videos..
I like the idea; for a larger set you could use either the half height or full size unistrut the bending would be a trick but it is doable. Thanks for the idea not it's off to the shop.
muito bom
why all the holes? is that for improving the flexibility of the steel? you make me think about things that is for sure, also you could make a cradle to hold the cauls so you can load your glue up directly to the bottom cauls, and i was thinking how I could add threads and bolts to the ends of the cauls to assist line up and improve the clamping pressure too with least amount of clamps and hardware. It's got great potential so well done 😀👍👍
Maybe we could talk Matthias into measuring the pressure gradient across the cauls for optimum bend angle haha
The holes are only there because that's how he bought the tubes. Look up "punched square steel tubing".
cutting or drilling steel does not create tear out. It is called a burr :)