So I spent a couple hours playing with the steel tubes and sheet and it took a few tries before it actually held together. The solder would fall on the ground and not stick or suck in, until I somewhat got the right procedure, I think
Here is what worked for me:
- used a 3/16 file (same diameter as tubing) to file the tube and get a proper fit between the twopieces.
- dip the two pieces with flux paste everywhere you want the solder to go (in between the pieces as well as on a small lenght on the outer surface, it will make the solder reach farther on e pieces fr a stronger solder).
- heat until the flux all melts and the piece start changing color. For me it takes maybe 10 seconds?
- add the solder to the mix while heating, the solder should be sucked by the pieces.
- stop heating for a couple seconds, and then I added some solder where I want a thicker solder, where the two tubes meet.
- a kind of droplet forms, so I slightly reheat so it takes the shape I want and it goes where I want.
- let it cool (if you undo the vise everything might come apart as the solder is still liquid)
- clean with a rag and then buff/sand if like me your solder looks ugly
Here are some pictures of my first successful attempt, I just bent some 22 gage steel in an L, then tried to joint two pieces at an angle. Also made a T with 3/16 tube and attached this to the L. Not a real piece for my project, just some tests:
Came out real strong when done right. I am still testing what makes for a "right" solder though hahaha
By the way to solder the tube to the L bar, I slit the end of the tube in two with a metal saw, so it would slide on the L, and then tapped with a hammer to flatten the tube on the L. Of course I first sanded and put flux everywhere, before making the mechanical fit.
I use a bench vuse to hold the work, but I'll have to find those magnetic thingies that hold the pieces together, because the bench vise will not work for all pieces shapes.