tbrforge

quoting a circular staircase

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Hello to all:

I am quoting 60' of railing with a 10' tall circular staircase. Railing quote and execution is no problem, especially since the customer wants a replication of work I have done for others in the building. But....I am trepidacious about the staircase.

I have been researching kits that can be procurred online as opposed to starting from scratch.

Any comments, ideas or loud guffaws will be appreciated (well maybee not the guffaws)

Terry
TBRForge
Athens,Ga

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Just to be clear, by circular do you mean what is usually called spiral but is actually helical?

What ornamentation is asked for? I know I have multiple levels of work, basic stuff is from commercial components with generic elements put together in a pleasing way, next would be simple but truly hand forged work assembled well, and then on up to very ornate all original truly hand forged work that is considered art. While I generally quote only by the job, price for iron work like this starts at $100 a linear foot and goes upto to about $400 or $500 per foot. That is just the iron price and when I make a final quote I add in the installation costs.

What is the installation going to be mounted to ? Wood? concrete? Indoors or out?

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Terry, I have never done a spiral (helical) staircase, so hesitate to offer any advice since it would be all second hand. But I wanted to offer that there is a page or two in "Forged Architectural Metalwork" by Peter Parkinson that address the spiral railings, and a snippet in Whitaker's "The Blacksmith's Cookbook". Neither is sufficient, in my opinion, to tackle the stairs, but between them there is probably enough information for the railing portions of it.

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Ok more questions for you. Are you talking about a stand alone spiral staircase that goes straight up a pole? Or are talking about a railing for an existing staircase?

If you are talking about creating a spiral one on a pole thats actually fairly easy. It is designed the same way that a regular set of risers and treads is done for a a straight staircase. Height (10 feet) divided by the height of each riser- say 7 inches. 17 steps roughly. If you add a platform or landing at top , one less. I am looking at my own staircase and can see how easy it really is , only I am not the best teacher. It goes up eight feet and has twelve steps and landing at top. Each step is 12 wide at the outer edge.

You could adapt or modify a commercial set, but it ain't that hard to do the math. I'll try to write a more coherent description of the design I would use. I have had to do trigonometry three times this week on blacksmith projects and my brain still hurts from it.

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Mark,
Concrete base floor, framed in at the top.

I am submitting the quote in the plain ole vanilla wrapper ( no frills) and the artistic concept I have envisioned for the customer. This is for his Rolfing Studio.

I was happy to read your reply because I quoted the railing @$80.00 per linear foot and was thinking of going up to $150/ft for the stairs.

I'm going to research the books today. I am still a bit fuzzy about individual tread support.

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Howdy. Happened by this site a week ago while I was dreaming about doing some blacksmithing. I'm not a blacksmith or any sort and have only started to do some metalwork with an oxy-acetylene torch set (eventually want to braze a lug bike frame together.. but I digress)

Anyhoo.. saw your post and wanted to suggest you take a look at "modular spiral staircases" (google it up) Spiral staircase and modular staircase kit products (has installation videos also)
They are simple construction where each tread is separate and has a heavy tube attached. This is your main support for the treads. The tube usually slides over a central pole. There is usually a small connection at the outer circumference between treads to hold them in place. This design keeps the outer circumference very light as there is is not a heavy helical beam there.
It appears some rely on the railing for support also (at least on that linked site)

I saw one being installed many years ago on TV (I'm a This Old House type person)

Anyhoo.. good luck in your venture.

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The commercial staircases are a good way to see how to construct them. I concur on the central pipe theme with larger pipe sections that slip over the column for each tread. These can simply stack if cut from the same length of pipe as the column and then divided into equal sections for the treads. I just drill two holes and thread them 3/8-16 and use allen head set screws to keep them from turning. For the pickets I would use two for each tread( that keeps the math to a minimum and all of them the same size), both of which hang over the edge and attach to the next tread as well, one up from and one hanging down from.Two holes in each down low will allow you to space the treads properly. Using pipe for the hand rail is the simple solution, either weld in place after bending, or drill thread and bolt, or drill over size holes and toggle bolt into it. flat stock is a little harder to get to bend to that shape, but can be done too.

As to support for each tread, it depends on the material that you want as the tread. If metal is the final, then simple angled pieces of plate welded under the tread and to the pipe section can work. If more decorative wood is to be used then construct each tread/step as a frame attached to pipe and then use rod from the outer edge of the tread to the lower edge of each pipe section.

If you have trouble visualizing what I am talking about, I'll get off my lazy butt and make a sketch.LOL

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the support thing has me a bit baffled. I downloaded a pdf file from a kit manufacturer, and I follow the idea of treads stacking. I don't like all the bolting and such with the kit, but suppose I can substitute welded connections.

BTW loved your site Mark, I'm in Athens Georgia, where are you?
you work with a glass artist? any luck putting glass in the "eye" of andirons?
been trying that for several years with no luck just lots of cracked glass.

the staircase will be tied into the railing at the top. the simple version is to use "Hog wire" (welded 3" sq. 3/16" dia.) as balluster. I'm not going to be able to get the guy to go with my artistic rendering. The minute I spoke of what I envisoned, he got that deer in the headlight look and said he couldn't afford that. Oh well, I'll TIG every thing so it will still be "artistically rendered" I will not compromise on my level of quality.

I would like to "talk" to you about how your business evolved, I have 20 years experience working for others in the trade, but have only been independant (starving artist) for around a year. I need to get a web presence up and have a million questions to throw at you, but don't want to impose on your generosity or time so if you feel inclined I enclose my email address and a deep felt thanks for all your help.

Terry
TBRForge
[email protected]

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boy am I dumb, I just noticed that all the post carry info as to location. West virgina huh? G_d would I like to visit you with an empty truck and come home with some good coal!

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You still aren't clear as to the layout of the staircase. Whatever the case, do the math, make certain the math is correct, take into account everything, make the jigs for the treads perfect as to the math (this is critical), do not deviate from the the math because while something might look awry while it is going together - it will be right when it is done (it will look screwy if you 'make adjustments' to it while it is half done. Anything else?

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the math is not an issue, I work every project out on AutoCad. One of my concerns is the wrapping of the handrail. Seems as though the handrail is intergral with the ballusters and tread to give the treads the support needed on the outside of the radius. Been searching everysite I can and looking at pictures. No staircases around here to observe. I have never been accused of underengineering, but this sure isn't the porject to make assumptions on eh?

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layout wise, I have an appointement with Inspectors on Monday to talk code. Looks to me Like I need a rise of 9" giving me 12 steps. only going from ground floor up 10' I am going with 30 degree coverage on the outside of the tread. 1" sq tubing (weight concerns) 14ga wall for ballusters 1-1/2 round for handrail.

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TBR- You can email me off list for any questions at all about running a blacksmith/welding business. Or for that matter you can start an thread with some questions and let all of us business owners chime in.

The math and design sounds good, although the 1.5 inch rail seems a bit thick. Maybe 1 inch or 1.125. Thats just my opinion I don't see anything wrong with thicker.

I am guessing you'll adjust for the .333 difference in the math on number of risers? 10ft=120in divided by 9" rise = 13.3333333333 and so on. -1 gives you 12.33 steps. .33 left over. Divide this up to add to the 9" to get actual rise.

Most important part to remember is that the center post is not the only support. One of the balusters must "hang" down and support the next step thus creating a stepped support for the outer edge of each step, both supporting by hanging a contiguous section and then at the bottom step this attaches to base or floor giving support.

Fully cantilevered suspension type stairs can be troublesome.

Oh and I am in such northern WV that I have to buy Pennsylvania coal.

Annealing very slowly will help with the glass , although you cannot eliminate the cracking totally. Unless you cheat like I do and have the glass department make inserts to fit my openings then epoxy or use welded tabs to hold it in place.

I could be wrong , but I doubt it. LOL

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I worked in a custom wood shop once where my boss told the story of making a handrail for a circular stair and having to screw the helix through the front door to get it inside to the stairway.

Just a cautionary note....

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I plan on fabricating the handrail on site, weld and bend,weld and bend...
First shop I had, I built "the boat in the basement" a truck rack out of tubular stainless. ended up removing the door jam and still had to squeeze the rack through.

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