Next Railing Project

[dgoddard]

As Part of our remodelling project my last project was to make custom railings for our custom poured front steps, (pretty much had to given the flimsy ready made railings proportioned for some sort of standard steps). I am reasonably satisfied with how that one came out.

The stanchions and railing are 1x1-1/8 wall square tube, and the cross-bucking is 1/2 inch rebar.
The steps were poured 4 feet wide in front of a 36 inch door and were not wide enough to accommodate fastening the railings to the top surface of the steps and landing, so I opted for extending the stanchions down the side of the concrete and mounting them that way.
The mounting details were done like this.

Knowing that some of the mounting studs would have to come out near the edge of the concrete I did not want to use expanding anchors so I opted for embedding threaded rod by grouting it with "JB Weld" epoxy. On the left is one of the longer stanchions but on the right is the lower step stanchion where the "closeness to an edge" problem would be more evident. Also show on the right is a shim on the lower attachment that was required to accommodate a 1/2 inch irregularity that occurred on both sides at the bottom step. The disk at each mounting is threaded onto the rod so that when tightening up the nut, there would be no tendency to jack the rod out of the grout. Shims were also made to accomodate any misalignments at the other attachments but the rest of the concrete and the railings had little need for them. All the upper fastners were equipped with a 1x2 x0.25 reinforce to prevent an outward force on the stanchion from buckling the stanchion at the hole for the threaded rod.

If you were wondering how I got studs in the concrete so that 8 studs lined up with 8 pre-drilled holes all at once, there was a little trick to make it easier. The railing was supported in position and using a bushing, a 1/4 pilot hole was drilled in the concrete through 2 of the railing holes. This was enlarged to 3/8 with a "free" flanged bushing that helped to keep the drill perpendicular to the concrete face. (Note you cannot run a 3/8 masonry drill through a 3/8 hole made with a twist drill, hence the "free" bushing.) After studs were set in these two holes the railing was mounted on them and the drilling was done on the other 6 holes. Then studs were placed in the other 6 holes and while the epoxy was still fluid the railing was replaced. The fluid condition of the epoxy allowed an extra degree of wiggle to help get the studs through the holes in the railing. No real difficulty was encountered on either side.

And now we get to the problems of the next railing.

As soon as the weather cooperates I will be having two approximately 20x20 slabs poured. One for a tractor shed where the car port will be reassembled, and one in front of the garage so we have a good clean entryway area to the garage. However on one side of the garage entry area there is a retaining wall with enough height to cause an injury if someone stepped off it. So I will be putting a railing there. The railing will turn a bit of a corner at the end far from the garage, hooking in toward the driveway. It will be 48 inches high. That is a bit high for the usual railing but in his case i want it to be high enough to be readily seen from a car, especially when backing up.

Having burdened my material budget recently I have decided that this 2nd railing will be built with some 1.5 inch pipe (1.9 OD) that the previous owner had left laying around. There are however a few problems.
1.
The pieces long enough to make the top rail are galvanized. The galvanizing is well weathered and I expect I will have no problem getting paint to stick, but then there is the matter of welding. The welding might be done out of doors using flux core wire except the butt weld of the two galvanized pieces to make the top rail, that weld will be MIG welded indoors where I have a bit better conditions for aligning the weld. To prevent problems with zinc fumes, I would like to know how far back from the weld site I should clear the zinc off of the pipe before welding so as to avoid zinc fumes. Also if any zinc gets into the weld, how much of a problem that will be for the weld strength. That is to say if there is a trace of zinc that gets into the weld is it going to be deleterious to the weld.
2
In addition to the zinc issue, there are some design issues. I could just MIG weld the whole thing in my basement that would then leave me with a weldment of approximately 115 pounds to deploy to the slab before during or after the pouring of the slab. For the moment I foresee 5 possibilities for the railing design. Basically all deal with how and when the railing is attached to the slab.
1-- Make up the entire weldment (top rail plus 5 stanchions), position it and pour the slab around the bottom of the stanchions.
2-- Pour the slab with sockets in it and place the stanchions in the sockets and then mount the top rail and weld it. then grout the stanchions into the sockets.
3-- Pour the slab with sockets, Make up the entire weldment, Set the stanchions into the sockets with the railing already attached (but would they come out accurate enough) and grout the stanchions into the sockets.
4-- Pour the slab without sockets. Make up the stanchions with square flanges on the bottom. Mount the stanchions with fasteners to the slab, Place the railing on the stanchions and weld.
5-- Pour the slab without sockets. Make up the entire weldment, (railing and stanchions with square flanges on the bottom). Mount the stanchions with fasteners to the slab.

Of those options, a lot depends on the accuracy with which various dimensions can be achieved, such as the straightness of the concrete the alignment and positioning of the stanchions etc. I plan on "fish mouthing" the tops of the stanchions but I see their accurate attachment as being a bit tricky. And I tend to favor option 4 as the one I might trust the most to get dimensionally correct but i would welcome suggestions from those who might have more experience with the various aspects of this project so that it does not come out looking sloppy. Option 1 also complicates things for the guy that is going to do the slab work in having to work around the railing. The sockets it turns out are actually fairly easy to create, as they are accomplished by placing soda cans (full so they will hold their shape) into the concrete when it is poured, but that of course raises the question of how accurately they will be positioned.

Of course my 5 scenarios are not necessarily the only way to do it. Any that require welding on the parts together with part of them already mounted are dependent on my ability to find a way to power my welder at that location. So any suggestions or slick tricks that I have neglected will be appreciated.

[steamin10]

Good enough, looks strong for the need.

In new construction where anchoring may be a problem, we use pads set in the concrete, carefully measured from the form edges. The easiest way if you have a savy crew is to set up line stakes, several feet from the form, to grid where the footplates must land. A chalkline then will cross where x marks the spot. So the last step before leaving the slab is to poke the J-hooks that are welded to the 4x4 or 6x6 plate (1/4 inch or 5/16 thick, for small work.) two such hooks that reach into the slab give you a good hold without slowing up the flat work. Any convolutions of the slab that make a leg long or short, are delt with, when the railing are fixed to the plate. The rebar hooks are bent into a C shape and wellded easily to the underside of the plates to be used. this gives you a bit of shift should anything be off by a few fractions. Prep the pads with anti rust red and good to go.

Using this method we have built bases for steel arch buildings, set on piers (sonotube) at the anchor points, with the structure beams finish welded when they are erected. Interior finish grades are then filled, set, tamped and slabwork completed after erection.

Another method I consider less desirable, is to drill holes an inch larger than your standards (post) plop the assembly in the hole and fill it with anchorlock or similar quick set, in the hole around the post. Ample post length must be allowed up front, 6 inches is about average. Everybody has their own take on that. Drilling holes in green concrete, only a week old is fairly easy, provided you get tooo close and blow out the edge of the slab. This is an issue with all holes in slabs that have posts and things that tend to be pry bars and break edges anyway. The larger the setback, the stronger the edge, otherwise I have seen perfect triangles broken out of slab edges. that way.

You should not be welding over zinc, period. A small angle grinder will remove the zinc coating and do your fitup trimming for your welding anyway. The zinc will most likely burn off, but will lead to adheasion problems, and burnthroughs at the joints. If your Mig is happy doing small pipe welding, at least for me it is easy to get all positions for the weldout. If you cant get the heat right, your done anyway.

This last year I made a bunch of 6 foot fence panels, that were based on cyclone fence top rails for the structure. A divider post and custom sized door was made to fit in the panels. So each ten foot panel had about a 26 inch door fitted into the panel, and these are used for my portable pens, where the yard wire is simply strunf on conduit posts pounded only about a foot in the ground. This thin material is a pain not to blow holes in, and the hot dipped galvanized is (mostly) removed, as when you arc over the galv, it blows the core shield wires pool apart, and you blow a hole into the thin material. Teh Blue-green flash and white smoke says it all. It tells you when you got it wrong. After welding this stuff together, a spritz of galvanized paint hides the joint and gives it some rustproof life.

I can dial down to weld 3/4 and 1/2 inch EMT as it is electro galvanized, and can blow it off and get a good weld on that super thin material. It makes for strange yard ornaments. I am going to try for a few dinosaur skeleton beasts, and see how it goes. This stuff is cheep, and I have a bout a hundred pieces of bent conduit shorts from school to play with.

Someone will probably steal George, that is a huge plastic turtle. The goal is to move him every morning, while he is visible to the street. His shell is over 2 feet across, with his head raised. thats all I have to say about my play. More than one way to do things, just do it.

[redneckalbertan]

If I was doing it I would place embed plates in the concrete and then weld railing to the plates. If you aren't able to do that my second choice would be to weld the plates on the posts when you build the railing and then hammer drill and anchor the railing that way.

I would take off 3-4 inches of the galvanizing from the pipe, as well WEAR A RESPIRATOR (properly fit of course). Zinc is not fun to inhale and the effects are not fun to live through. Google 'metal fume fever' if you want to know more about the effects of zinc fumes on the human body. Using a grinder can miss some spots and strips of zinc which is where the respirator come in.

I don't know what you have for a welder but the little bit of zinc left over from grinding shouldn't cause too much grief for your weld.

[steamin10]

Redneck: I agree to disagree. yes, yes, no. Basically I thought I said that. The last pic is revieling, the bolts welded to the plate. Same as a C bent rebar, no? Same idea, diferent out of pocket parts.

In the end, more than one way to skin a Jackalope, and emperically some answers are better than others. I am mute on further visions. All the best.

[dgoddard]

..... I would take off 3-4 inches of the galvanizing from the pipe, .....

So are you saying that the galvanizing needs to be ground off the pipe for 3 to 4 inches in every direction from the weld???. that sounds a bit extreme for the size weld required on 0.150" wall pipe. I was thinking maybe 1/2 to 1 inch back from the weld. If I have to take it off 3 to 4 inches back, I would be grinding so much zinc that I would think there might be a concern from getting the same exposure from the zinc dust as from the fumes of welding.

The term "grinding" has been used. Is a wire wheel adequate for removing the galvanizing? I think I can hook the shop vac up to the bench grinder to take care of dust there.

I happen to have plenty of muriatic acid (HCL, Hydrochloric acid) left over from something else. How about etching off the zinc?

[Harold_V]

I happen to have plenty of muriatic acid (HCL, Hydrochloric acid) left over from something else. How about etching off the zinc?

That would be my first choice, as it's not only fast, but very effective. HCl goes after zinc with gusto! I'd suggest it be used diluted at least 50% (with tap water). If you desire a slower reaction, dilute even more.

Harold

[dgoddard]

Thanks Herold
I thought that might be the case.

Now if I can just get some more discussion about how far i have to strip it back from the weld.

[ctwo]

I was expecting to see train tracks...

[redneckalbertan]

If I have to take it off 3 to 4 inches back, I would be grinding so much zinc that I would think there might be a concern from getting the same exposure from the zinc dust as from the fumes of welding.

The term "grinding" has been used. Is a wire wheel adequate for removing the galvanizing? I think I can hook the shop vac up to the bench grinder to take care of dust there.

I would not use a wire wheel the zinc soaks into the pores of the metal. A wire wheel will remove the zinc on the surface you need to get below the surface. I would use either a grinding disk or if a finer surface finish is wanted try a flap wheel. Yes there is a lot of dust from grinding, my solution is to wear a respirator. It is easier to filter out the larger (relatively) dust particles from grinding than the fumes from welding.

Sorry Steamin I was tired last night and I don't think I read your post even though I read it. We did say a lot of the same things. The J or L shape rebar or round bar welded on the plate is just as good or better than the weld on studs in my picture, especially if you can hook them around the rebar in your cement work.

[Harold_V]

Thanks Herold
I thought that might be the case.

Now if I can just get some more discussion about how far i have to strip it back from the weld.

I'd hesitate to speak with any semblance of authority, but I expect that if you've cleaned the material a half inch beyond your weld, you're not likely to evaporate (or ignite) any of the zinc. Just guessing, mind you. I'm far more experienced with dissolving metals than I am with welding metals.

Harold

[dgoddard]

....I would not use a wire wheel the zinc soaks into the pores of the metal. ... Yes there is a lot of dust from grinding, my solution is to wear a respirator....

The use of the term respirator has come up more that once. But I am not clear on exactly what people mean by that. When I searched on "metal fume fever" and found a bit more on "respirator" they were talking about a respirator with an air feed to it but were also apparently writing about somebody who works an 8 hour shift every day around welding this stuff.

I would think a good dust mask would probably suffice. However at the present I am favoring masking the zone of removal and using acid to remove the zinc, and that will probably also get any in the metal pores. I had to etch a small amount of concrete and the smallest size available was a gallon of muriatic acid (HCl) so I have plenty with no other pressing need for it.

[steamin10]

You are dealing with dust, (smoke particles), so most people settle for 3m type filter masks. They are admittedly not great, but your risk here is low, so thats where I would start. I also have full cover chemical masks for painting, and used full chemsuit sccba equipment for environmental entries. Way overkill for your need. Kiss rule. Not a bad idea to use a dust mask when welding or grinding anyway. I know of too many welders that die of lung Cancer. Draw your own conclusions.

A half inch in the weld area cleared of zinc is plenty, the sweep motions of the grinding disc often makes it out to an inch, but the half inch is the weld area, and thats it. Dont overdo it. I prefer to leave the inside alone as the residual zinc that doesnt burn away leaves future rust protection. Railling nearly always fail at the joint for pipe. Weld transition metal point on ornamental work. I touch up my iron work every year, wherever a rust streak shows. Full paint if it looks shabby. Always wire brush the rust.

If you must use muratic, it is pretty easy on the body, except for fumes. A splash isnot serious, just rinse it off, it takes time for it to act on skin. Eye protection is mostneeded. A plastic milk jug is a good conatainer for a small amount, and what is not used can be returned to the parent bottle if you dont mind the small contamination, it will probabaly have some life in it, or just dilute, and pour down the drain, or outside on limestone gravel. If left in the sun for a day or two open,it will gas out, and only what has disolved will remain as a salt.

DONT PUT IT IN THE GARAGE. HCl fumes rust the bejeezus out of steel with just atmospheric humidity.