Stair railing for spiral staircase?

[11b]

I was wondering about the railing for a spiral staircase I want to build for a log home. The way I understand it is if I bend the railing in a 1/2 of an arc, I can then weld said railing to the picketts. I was checking out how Wendal Moon on You Tube did his and it made sense. It looks like he just bent it in a 72'' radius which is what his staircase diameter is. Is there anything more to this? It almost SEEMS to easy. I searched a lot of places and everybody seems to be scared of the railing Thanks for any input.

http://www.ehow.com/videos-on_5001_p1_build-steel-spiral-staircase.html"]
http://www.ehow.com/videos-on_5001_p...staircase.html

[aametalmaster]

Yes it is a radius but when it comes out of the rolls it is level and flat. It will need pulled up sort of like a slinky to touch the pickets so it will need another radius put in it to match the spiral. The trick is to keep the top of the channel flat for the rail without twisting it...Bob

[11b]

A slinky,,yes I can understand that,,now I wish I had one to figure this out. Do you think that it is possible to force it to the pickets? In the video it looks like he is just setting it on the pickets. I kind of see what your saying but i am still a little confused. I think maybe he is forcing it to the pickets???

[aametalmaster]

Yes he is setting it on the pickets but look at it when he and his helper are bringing it up the stairs it looks like a giant spring shape like a slinky. If you just force the rail it may twist on the top and not be flat. Round bar may work better and you won't notice if it isn't flat on top. There is a way to roll so there is a radius in two different directions i used to do it all the time with round handrails. You just need to stagger the dies a little so the tubing or channel bends like a curly Q. I don't know what kind of roller or machine you have either. I can roll small tubing exactly like i described but i am limited on size. I roll 72" parts all the time and i just did 100 pcs a few days ago...Bob

[Jack Olsen]

Which makes me wonder -- does a slinky change diameter when it's compressed and extended? I seem to remember something like a 3-4% rule for springs, but I don't remember if that involved the ends being fixed or not.

[11b]

I dont have a roller and was going to farm that one out.
Ok, so you think he is using some pressure to get the slinky shape or he left out that step you desribe as I will correctly or not call a "compound radius?" And you mean you rolled a 72'' radius or the stock was 72'' in lenght? I may have to go to round tube but it seems like that flat stuff should work plus its easier to fit to the pickets. Notching all those pickets could make a man batty Thank you for the help BTW

I think a slinky stays the same Dia.

[davedarragh]

There are two very good books available to help with this:

Builders Handbook, Craftsman Book Company, Carlsbad, Ca for $15.50 (check Amazon)

Building Layout (using transits, levels, etc) by the same publisher $22.00

I have the 2nd book, and there are 2 chapters on the layout of the arc radius, tread and stair risers, and all the formulas.

They are just too numerous to quote on this Forum.

Hope this helps

Dave

[aametalmaster]

And you mean you rolled a 72'' radius or the stock was 72'' in lenght?

My parts were 66" long to start rolled to form a 72" circle not radius my mistake...Bob

[11b]

Thank you for the help. I am buying those books!

[andyman]

My work does spirals(we got one coming up soon actually) and while i havent seen them bend the hand rail my boss has explained it to me. we have a bender that is vertical and we make ours from 2"( i belive) aluminum tube and my boss has figured out a formula so that over say 3feet he knows he has to turn X amount of degrees. We usually always get it close enough to make it work.