metal frame steady rest joint question

[curtis rosche]

i went out and got some 1 inch square steel tubing. the edges are rounded over so its not a sharp corner. the question is how to weld the corners together. i am going to make it a square frame. can i just weld the 2 peices together end to edge. or should i cut the ends on 45 angles and weld that together? will it make a difference other than apperance?

[Dan Ewalt]

You can weld them as they are if you want. When you do a butt weld like you will have when you join the side of one piece with the end of another its actually beneficial to have a small valley between the two that the weld will fill. It's not AS important with the small (I'd guess 1/8) thickness you are dealing with, but as the thickness of the metal increases you would make a 45* angle cut on the edge of one or both of the pieces to get that gap. Then make a root pass followed by additional passes to complete the weld.

All that said: you can, if you want, cut them at a 45 and weld them that way as well. The outside corners will look a little better and again with the thickness of that metal you should get good penetration even with a tight butt joint.

What process are you using? MIG? and what size of machine?

Dan

[curtis rosche]

i am told the machine my brother has access to is an arc welder. small size, like in the price range of a college student who shops at lowes. if it doesnt work, my brother also has access to a top of the line TIG machine. but that shouldnt be nessesary since it is only 1/8inch thick. i would do it my self but its not my welder to use

[Ryan Baker]

Welding 1/8" (if it is even that) tubing with a stick welder will take some effort. I hope you can turn the amps WAY down or you will be blowing a lot of holes in it. MIG would be a better choice and TIG a better choice still. But if you have the skills, you can make the stick welder work.

[Dan Ewalt]

Yeah agree with Ryan. You'll have a tough time getting it done with a stick welder without blowing holes in the metal. If your brother is a good welder with some time under his belt he should still be able to do it, but it won't be the best process to use for what you have.

If you can I'd take whoever it is up on the offer to TIG it.

If you were anywhere near me I'd tell you to pop on over, but 500 miles is a little bit farther than you'd want to drive I'd assume :)

[Richard Madison]

My welding ability is surely nothing to write home about, but have no problem welding 1/8" material with an inexpensive AC stick welder (Lincoln 225). Given a choice I would make 45 degree corners, as they should be just a bit stiffer. Make the frame as small as it can be and still do the job you want. Smaller will be stiffer. If square frame, do 45 degree corner braces to increase stiffness.

[Phil Labowski]

it's been a long time since I held a trigger, but both fab shops I worked in used tubesteel (or HSS) and they used MIG welders. Mostly for the blow through reason I believe. If it was me I'd have him TIG it so your project doesn't take twice as long trying to deal with holes.

[Chris Stolicky]

45 degree corners is probably a better bet. You could also add gussets to the corners if you need more stiffness.

[Richard Madison]

All the comments on blowing holes in 1/8" material prompted me to check the angle iron steady rest frame I built a few years ago. Turns out that the material is indeed 3/16" thick, not 1/8". I remain convinced that 1/8" could be stick welded relatively easily, but also agree that mig (smaw) welding could yield a better result. Tig (with mild steel) is ordinarily used for very thin material (auto body panels, for example), and might be considered overkill for 1/8" material.