All things welding
- Thread starter AirborneTexasRanger
- Start date
OP
I used one of these when I was repainting my diff cover. They do work really well!
Those are great for reasonably sized jobs, but I used the 4" version and went through a couple of them before making enough of a dent in what I had to do to keep buying them. It wasn't a jeep project, it was about 300 linear feet of rectangular and square tubing and flat bar to make the railing for our loft and stairs. I made a tank out of 3" PVC pipe and could get the material for one railing section into it and let it soak while I welded and painted the section before it.
Where do you buy them? I didn't look everywhere, but I tried a couple places locally without any luck.
Yeah. Sounds about like the vinegar. One of my biggest challenges was the fact that I was doing it in January and acid works a lot slower when it's cold. But it was still waaaay better than doing it manually.
Not sure where you buy your material but I have never bought any tubing small enough to make railing from that had mill scale. 4" aren't worth buying and I will have to dig up where I got the last box.
just a steel place in an industrial area in west Oklahoma City.
I don't recall exactly what the top rail was but the lower pieces were 3/4" square running between strips of 1/8" x 1". It was indeed relatively small stuff, and the scale wasn't as thick as I usually see on angle iron for example, but was gonna be inside the house, the expectations for paint longevity were high, so it had to be spotless before I painted it.
You are impossible at times. The discussion was removing mill scale for welding. I guarantee you that small square tube did NOT have any mill scale on it, I've never seen any in the 1000's of lineal feet I've used over the years that does.
Welding is a tool that we use for fabricating stuff. The other tool we use is our brain. That part of fabrication takes into account the entirety of the project and the time involved versus what we want to accomplish. If I was doing that job, the material would NEVER have to have that much prep done to it. That flat bar would be cold rolled. The square tube would be inspected for mill scale (next to zero it had any) and a suitable material selected that didn't require prep other than deburr after cutting. And before you assume, I have done tons of stuff like that under those parameters so I know how to do it.
For that exact project though, nary a drop of paint is going on that. My powder coater is doing that job and he'll do it exactly how I want it. (It is fully okay that you painted it, I just won't do that for interior stuff where I want it durable and perfect)
The only exception to that is a set of fireplace screens I built from scratch.
OP
It looks like you bent the flat bar so it overlaps on the ends. If so, that's a really good design.
I did, I wanted a hint of blacksmithing in the design.
It was dull gray shit all over the metal that wouldn't allow for paint adhesion and needed to be removed, and was responsive to common mill scale removal techniques. Tell me what you want me to call it so we can move on. All I did was suggest a lazy method for removing it from large areas, a method corroborated by another poster, and you're stuck on your 3m disks being the better way or something, I don't even know.
As much as I'd have rather it been powder coated, I had from the time the painters were done to the last day of my 9 month mortgage rate lock, to get all these fabricated, painted and hung and then inspected and appraised, while also working my day job.
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OP
For what it's worth, I think you did a great job. It looks really well made.
I think it's possible that y'all are taking about 2 different types of square tube. Hot formed tube such as A500 or A513 will have mill scale while cold formed tube such as 1018 will not
I think it's possible that y'all are taking about 2 different types of square tube. Hot formed tube such as A500 or A513 will have mill scale while cold formed tube such as 1018 will not
Thanks! And you're probably right. If I'd known going in that I might have the option to specify and avoid the removal process, I probably would have. I walked up to the counter and told them the dimensions and cut lengths worked out to fit in my pickup with minimal generation of falloff, she jotted it down and called me the next day when it was ready.
I did end up cutting too much off one piece and went to Lowe's for a replacement. The one from Lowes was conspicuously free of scale, but I didn't put much thought into it at that point.
I hope I don't get any pee-pee on me from stepping into this 
, but I think the confusion is regarding tubing vs. solid bar stock. Almost all small, thin-wall tubing is made via a process sometimes called CREW (cold-rolled, electric resistance welding). The process starts with hot-rolled flat stock, and it is reduced thinner via cold-working, then cold-formed to final shape (round, square, or rectangular) and welded. The mill scale comes off during the cold reduction and the cold-forming processes, so it has a clean finish. On the other hand, bar stock can be either hot-rolled or, as AirborneTexasRanger pointed out, cold-rolled. It's the hot-rolling process where mill scale forms. I think Mr. Blaine had tubing in mind, but I think freedom_in_4low actually used hot-rolled bar stock for the railings. After all, it would be very difficult to mistake the clean surface finish of cold-rolled steel for mill-scale. Depending on the skill of the mill operator and how long the steel has say in inventory, it can actually have a shine to it.
, but I think the confusion is regarding tubing vs. solid bar stock. Almost all small, thin-wall tubing is made via a process sometimes called CREW (cold-rolled, electric resistance welding). The process starts with hot-rolled flat stock, and it is reduced thinner via cold-working, then cold-formed to final shape (round, square, or rectangular) and welded. The mill scale comes off during the cold reduction and the cold-forming processes, so it has a clean finish. On the other hand, bar stock can be either hot-rolled or, as AirborneTexasRanger pointed out, cold-rolled. It's the hot-rolling process where mill scale forms. I think Mr. Blaine had tubing in mind, but I think freedom_in_4low actually used hot-rolled bar stock for the railings. After all, it would be very difficult to mistake the clean surface finish of cold-rolled steel for mill-scale. Depending on the skill of the mill operator and how long the steel has say in inventory, it can actually have a shine to it.
Not all HREW looks like that. That looks like Type 1B. It’s pickled (acid bath) and oiled before forming to remove scale.
I've never had a stick of square or round HREW that wasn't bright like that. DOM is the only thing I use that isnt.
Thats just regular old cheap ass India or China .08something wall 1"
Thats just regular old cheap ass India or China .08something wall 1"
I hope I don't get any pee-pee on me from stepping into this
You won't get any from me
It was definitely tubing, not solid...16 gauge wall thickness to be exact.
I'm first to admit I know enough to know that I don't know what I don't know, but I definitely know what clean, bright steel looks like. I looked for my receipt to see if I could find out what I actually bought, but no luck.
What I did find was a few photos of the raw material.
And one of my first completed section, before I prepped for paint, and before I'd learned about the acid bath. if you zoom in around the ends of the tubes you can see a couple inches that I cleaned up before welding.
Whatever the stuff was, it didn't come off with acetone, a stiff wire wheel on a grinder took a lot of time and pressure, the 3m wheel was much better than wire but was still going to take a lot of time (and wheels at $25/ea), but 24-48 hours submerged in vinegar and it was good to go.
So it was tubing, after all. And that tubing definitely looks like hot-rolled (Type 1A - not pickled and oiled). The trouble with steel resellers is that they often don't know all the different standards. Type 1A is not very common for the exact reason that you discovered...