Hi, I need to weld a simple column. 4x4x1/4” square tube (approx 30” long) welded onto a flat 1/2” plate (approx 8x8” square). I’ll be TIG welding (don’t have a MIG), and I don’t have a fixture table yet.
What’s the best way to set up this weldment using Fireball squares?
Should the tube be placed horizontally, with two squares positioned opposite each other, holding the base plate with clamps? Or should the tube be vertical, held in place with a 3-axis square? In this case, I’m not sure how the square could hold onto the base plate.
I’m an amateur wanting to learn; all suggestions are welcome.
Jason has a video about that type of plate to tube that covers some of that. It also covers ways to keep the plate from becoming a potato chip, a very common issue with welding things like that.
3 axis square or a 12” mega square with tabs. Definitely stand the tube vertical so it can be tacked or fully welded in a flat position. It’s possible to do it laying horizontal you’ll just have to get clever with the set up.
Thanks for the quick answer! I’ll probably go with a 3-axis square.
Two questions for you guys.
What’s the ideal weld sequence? And, is it okay to reposition the square during the welding process? ex. weld one side, move the square, weld opposite side, etc
A TWO INCH HOLE DIRECTLY UNDER THE STANTION IS STRONGLY ADVISED (See comment below AND Jasons video on weld distortion.
Tack with minimal heat soak to set the desired geometry. (After tacking, the weldment can be removed from any fixturing and set up for easy welding.) Tack three places, spread as far apart as possible to avoid parts pivoting (from filler metal shrinkage) on an axis defined by 2 tacks.
Barring posssible appearance considerations, weld in 2 or 3 beads, not one continuous all-the-way-around, to avoid concentration of heat soak.
My bad, “stanchion” was the word I was trying for. The (I assume) vertical post, that is being welded to the (I assume) horizontal plate. Sorry about that.
The hole is a recommendation Jason made. It allows the metal of the base plate to expand from the heat of welding into the hole, decreasing its diameter. Without the hole, the thermal expansion is likely to be constrained by the surrounding metal of the plate and while softened, cause a bulge in the middle of the plate. A bulge created by this expansion-then-cooling will not go away on its own.
Thanks! I’ll drill a large hole at the center of the horizontal base plate, directly under where the vertical 4x4 tube will be welded.
Is there a reason you suggested tacking in three places? I intended to tack the four corners of the square tube.
Regarding the weld, I was planning to lay ~2” beads at a time and to jump around to opposing sides. I thought this would prevent the material from being pulled in the same direction, all at once. Would this work?
Sounds like a good plan. Four corner welds is fine. Just more than two and keep them small. Two welds might allow sort of a “hinge” action with a gap created away from the welds. (With a square stanchion tacking diagonal corners would probably prevent the issue. But two adjacent corners (one side) might pull a gap at the other two corners (other side).
When robot welding car bodies at around one per minute we had a first weld station called “Geo Set” to set the geometry of all the parts relative to each other. Then to keep up the line speed the transfer moved the weldment through one or two “reweld” stations that added enough more welds to hold everything together.
Are there by any chance holes at the corners of the plate? If so, consider the difference between locating the plate by two adjacent edges vs pinning it by some combination of holes. Does the stanchion care whether it’s centered relative to the sides of the base, the corners of the base, or the (if they exist) mounting holes?