Results 1 to 27 of 27

Thread: Structural steel pipe for rails?

  1. #1
    Join Date
    Sep 2010
    Location
    World traveler
    Posts
    465

    Default Structural steel pipe for rails?

    George Buehler advocated welded plain steel pipe for rails, pulpits, etc. instead of stainless for both cost and reliability reasons since stainless weakens with little sign but on plain steel you can see the rust. His preferred look was black painted railings decorated with knotwork.

    I was looking at structural steel pipe and fittings used for architectural safety rails and other things, galvanized or black oxide, and wondering it that would work for a rough and ready workboat-style project. Here is a link to one manufacturer, there are many: https://www.steel-tek.com/

    Thoughts, pros, cons, alternatives?

    Cheers,

    Matthew
    *******
    Matthew Long
    Bolger fan (Brick, Yellow Leaf, June Bug, Tortoise and half a Teal)
    Dreaming of a small cruiser from Atkin, Bolger, Buehler or Parker
    www.cluttonfred.info (I also like homebuilt airplanes!)

  2. #2
    Join Date
    May 2012
    Location
    UK. Cornwall, Suffolk.
    Posts
    7,531

    Default Re: Structural steel pipe for rails?

    It's the way I'm going when I get around to it. Heavy wall hot dipped. For a wooden boat the joins to the boat are equally important...

  3. #3
    Join Date
    Oct 2008
    Location
    Walney, near Cumbria UK
    Posts
    52,621

    Default Re: Structural steel pipe for rails?

    ^ Yes, always hot dipped. That way they will not rust out from the inside.
    It really is quite difficult to build an ugly wooden boat.

    The power of the web: Anyone can post anything on the web
    The weakness of the web: Anyone can post anything on the web.

  4. #4
    Join Date
    Jan 2000
    Location
    Portland, Maine
    Posts
    20,988

    Default Re: Structural steel pipe for rails?

    Iíve used Steel-tek before. But not on a boat. Each joint is held by a single set screw. It was early pandemic days and it was hard getting all the parts we needed.


    8A6E3400-BC00-47DF-BBA6-F8CBAA2816D0.jpg

  5. #5
    Join Date
    Sep 1999
    Location
    Armada, MI, USA
    Posts
    291

    Default Re: Structural steel pipe for rails?

    Be really careful if welding galvanized steel. I welded a small project without grinding the zink away from the vicinity of the weld. The next day I had a really bad sore throat, but didn't make the connection to the welding. Shortly after that I did the same thing again and the following day I felt like my throat had been ripped out. Ever since then I make damn sure to grind any zink plating well away from any joint before welding. I suggest building with plain steel then plating the whole weldment afterward.

  6. #6
    Join Date
    Sep 2010
    Location
    World traveler
    Posts
    465

    Default Re: Structural steel pipe for rails?

    Thanks, all. Obviously welding is also an option, or maybe investing in a pipe threader and screwing the whole thing together, but the structural pipe is a temptingly easy solution. I wonder if you could use Loctite or something similar to strengthen the joints so the set screw is more of a backup?
    *******
    Matthew Long
    Bolger fan (Brick, Yellow Leaf, June Bug, Tortoise and half a Teal)
    Dreaming of a small cruiser from Atkin, Bolger, Buehler or Parker
    www.cluttonfred.info (I also like homebuilt airplanes!)

  7. #7
    Join Date
    Jun 2003
    Location
    Central Coast, Ca
    Posts
    30,461

    Default Re: Structural steel pipe for rails?

    If you thread the pipe you reduce the wall thickness (and strength) by half or more... and steel pipe fittings are usually cast iron.
    Bad idea.
    Steel weld pipe fittings are readily available in most configurations. Make a complete weldment with drain holes in discrete locations so that it doesn't fill up with Zinc when removed from the tank. The galvanizer can/will advise you on this detail or they will drill them. Most hot dip tanks are large enough to do street light standards, outdoor staircases, railings and etc. The shop local to me has a tank 60' long, 12' wide and 10' deep full of molten zinc. Just next to it is a tank the same size full of sulphuric acid (cleaning and flux). A seriously hazardous place, I love it!

  8. #8
    Join Date
    Sep 2010
    Location
    World traveler
    Posts
    465

    Default Re: Structural steel pipe for rails?

    I found this data on another sort of pipe fitting locked with a set screw, "A Kee Klamp fitting (size 5 to 9) can support an axial load of *2000 lbs (900 kg). per grub screw with the grub screw tightened to a torque of 29 lbs. ft.(39 Nm)." Size 5 in this case is 3/4" nominal (1" OD) Schedule 40 pipe. That seem to indicate that, if assembled carefully with a torque wrench, this sort of construction would be more than adequate for guard rails, grab rails, pulpits, etc. Source: https://www.keesafety.com/products/k...mp#techdetails
    *******
    Matthew Long
    Bolger fan (Brick, Yellow Leaf, June Bug, Tortoise and half a Teal)
    Dreaming of a small cruiser from Atkin, Bolger, Buehler or Parker
    www.cluttonfred.info (I also like homebuilt airplanes!)

  9. #9
    Join Date
    May 2012
    Location
    UK. Cornwall, Suffolk.
    Posts
    7,531

    Default Re: Structural steel pipe for rails?

    I have used Kee Klamp fittings for other applications, but would not use them on a boat. They use a grub screws to fix pipe ends.. this is not galvanised and will only provide one wee point of 'fix'. Better to make pads and weld all around, leaving drain holes as suggested.

  10. #10
    Join Date
    Mar 2009
    Location
    Texas
    Posts
    6,638

    Default Re: Structural steel pipe for rails?

    Quote Originally Posted by StevenBauer View Post
    I’ve used Steel-tek before. But not on a boat. Each joint is held by a single set screw. It was early pandemic days and it was hard getting all the parts we needed.


    8A6E3400-BC00-47DF-BBA6-F8CBAA2816D0.jpg
    Nice!

  11. #11
    Join Date
    Jun 2000
    Location
    Pleasant Valley NS Canada
    Posts
    22,969

    Default Re: Structural steel pipe for rails?

    Set screws? Never.

    Threaded fittings? Maybe, but keep exposed threads painted to slow down corrosion (they will always break on the threads adjacent to the fitting). Always use heavy pipe - Sched 40 at minimum.

    Welded fittings? Better.
    Hope for the best, but plan for the worst.

  12. #12
    Join Date
    Jul 2015
    Location
    St. Paul, MN
    Posts
    193

    Default Re: Structural steel pipe for rails?

    Iíve used Speedrail fittings with aluminum pipe a fair amount for temporary museum exhibits. When it came time to do one that would be permanent I was planning on doing the same until I realized it was cheaper to have it all welded. Those fittings add up fast. Iíve worked with my metal fabricator a lot so he gives me a good price but given how much more aluminum welding costs than steel I would think it would be cheaper and stronger to have it welded.

  13. #13
    Join Date
    Oct 2005
    Location
    seattle
    Posts
    19,484

    Default Re: Structural steel pipe for rails?

    A few years ago I added a rear deck rail to my boat using galvanized iron pipe and fittings. The problem was where the threads were cut, there was no galvanizing and it rusted no matter how much I scraped and repainted. Finally gave up and replaced them with bronze pipe. Pricey but well worth it.

    rustyStancion.jpg

    BronzeRail.jpg

  14. #14
    Join Date
    Sep 1999
    Location
    Armada, MI, USA
    Posts
    291

    Default Re: Structural steel pipe for rails?

    Use heavy structural tube. Make good fits and weld it up without fittings. Then get the whole thing galvanized. If George Buehler recommended "welded plain steel pipe", I suspect that is what he was talking about. Those cheesy set screw fittings might be ok for a front porch stair railing, but a boat's rail or lifelines should be able to withstand an adult man being hurled into it from across the boat. It would also look a lot better. Lastly, a fully welded assembly would spread the load over the assembly better. Those non-rigid fittings would likely put all or most of the load on only the nearest stanchion, possibly compromising the stanchion-to-deck joint, a never ending problem area on a wooden boat. It actually sounds like a fun project.

  15. #15
    Join Date
    Sep 2010
    Location
    World traveler
    Posts
    465

    Default Re: Structural steel pipe for rails?

    Quote Originally Posted by ron ll View Post
    A few years ago I added a rear deck rail to my boat using galvanized iron pipe and fittings. The problem was where the threads were cut, there was no galvanizing and it rusted no matter how much I scraped and repainted. Finally gave up and replaced them with bronze pipe. Pricey but well worth it.
    Interesting example, thanks. The bronze pipe is spendy but certainly looks good. I wonder if the galvanized structural pipe and fittings with the set screws would actually have been better than the screw-together galvanized pipe in this application. It would be easy enough to remove the set screws, grease the screw and hole, and then fill the screw head with grease after assembly to keep out the water. That way there would be no disturbance of the factory-applied finish.

    *******
    Matthew Long
    Bolger fan (Brick, Yellow Leaf, June Bug, Tortoise and half a Teal)
    Dreaming of a small cruiser from Atkin, Bolger, Buehler or Parker
    www.cluttonfred.info (I also like homebuilt airplanes!)

  16. #16
    Join Date
    Jun 2000
    Location
    Pleasant Valley NS Canada
    Posts
    22,969

    Default Re: Structural steel pipe for rails?

    This conversation seems to be going down a familiar path.

    Do not use set-screw fittings. Period. Full stop.
    Hope for the best, but plan for the worst.

  17. #17
    Join Date
    Oct 2005
    Location
    seattle
    Posts
    19,484

    Default Re: Structural steel pipe for rails?

    And please note on mine, it is the shape of the taffrail that gives it its strength. Freestanding bronze schedule 40 pipe, especially with threads cut into it, might not be strong enough in itself to take lateral loads.

  18. #18
    Join Date
    Jul 2013
    Location
    Aquitaine
    Posts
    1,461

    Default Re: Structural steel pipe for rails?

    I do quite a lot of railings, some for boats.
    Weld them.

    The exception was a stainless replacement for a wooden rail on existing stainless stanchions, where each stanchion had two screws going up into the wooden rail. Replaced it with 40x20 316 tube and pushed down a plate with two nuts tacked inside the tube to pick up at each fastening point (That was fun...)

    To add:
    Recently made a railing for a terrace, about 25mt long. Steel painted or galvanized or stainless. When one looked at the costs and the hassle of painting to a good standard, or carting off for galvanizing, for not much more and a really nice result we agreed on stainless. Client very happy.
    Last edited by Andrew2; 02-20-2021 at 12:49 PM.

  19. #19
    Join Date
    Mar 2009
    Location
    Texas
    Posts
    6,638

    Default Re: Structural steel pipe for rails?

    Quote Originally Posted by mmd View Post
    This conversation seems to be going down a familiar path.

    Do not use set-screw fittings. Period. Full stop.
    Just curious. Why not? What happens? Asking to see if it is a boat thing or also applies to interior railings in a house.

  20. #20
    Join Date
    May 2016
    Location
    Ottawa, Canada
    Posts
    470

    Default Re: Structural steel pipe for rails?

    +1 for MMD. If you can't realize what will happen to a set screw out in the environment over time then maybe don't build a boat.

    Cheers,
    Mark

  21. #21
    Join Date
    Jun 2000
    Location
    Pleasant Valley NS Canada
    Posts
    22,969

    Default Re: Structural steel pipe for rails?

    You are happily cruising along when you encounter a freak wave or big powerboat wash or sudden gust of wind and the boat heels suddenly, almost a knock-down. Losing your balance, you tumble across the deck and fetch up in a heap against the far rail. Because of the angle of the deck and the position of your fall, you actually hit the underside of the rail, forcing it up. At this point, your ability to stay aboard your boat - your life in the balance - is predicated on a single hand-tight screw jammed against the upright of your pipe rail, which is holding the pipe stanchion in place by the mere friction of about 4/1000ths of a square inch of metal on metal.

    I don't know about you, but I would not trust that very much.
    Hope for the best, but plan for the worst.

  22. #22
    Join Date
    Mar 2009
    Location
    Texas
    Posts
    6,638

    Default Re: Structural steel pipe for rails?

    Quote Originally Posted by mmd View Post
    You are happily cruising along when you encounter a freak wave or big powerboat wash or sudden gust of wind and the boat heels suddenly, almost a knock-down. Losing your balance, you tumble across the deck and fetch up in a heap against the far rail. Because of the angle of the deck and the position of your fall, you actually hit the underside of the rail, forcing it up. At this point, your ability to stay aboard your boat - your life in the balance - is predicated on a single hand-tight screw jammed against the upright of your pipe rail, which is holding the pipe stanchion in place by the mere friction of about 4/1000ths of a square inch of metal on metal.

    I don't know about you, but I would not trust that very much.
    Got it. Thanks. Iíve got a couple on my bimini but not critical. Am looking at some interior (home) stuff with set screws.

  23. #23
    Join Date
    Jan 2011
    Location
    Norwalk CT
    Posts
    1,715

    Default Re: Structural steel pipe for rails?

    Quote Originally Posted by mmd View Post
    This conversation seems to be going down a familiar path.

    Do not use set-screw fittings. Period. Full stop.

    Would you really trust your life to a 50 cent set screw? Or your kid's lives?

  24. #24
    Join Date
    Mar 2011
    Location
    Mukilteo, WA
    Posts
    3,403

    Default Re: Structural steel pipe for rails?

    Just to muddy the waters, plenty of boats have no lifelines- and virtually all pleasure boats made today have stainless stanchions held by set screws.

  25. #25
    Join Date
    Jun 2000
    Location
    Pleasant Valley NS Canada
    Posts
    22,969

    Default Re: Structural steel pipe for rails?

    Quote Originally Posted by J.Madison View Post
    Just to muddy the waters, plenty of boats have no lifelines- and virtually all pleasure boats made today have stainless stanchions held by set screws.
    A couple of points on that, Mr. Madison:

    1.) Many motorcycle riders do not wear helmets, but that does not make them safe. Rails & lifelines make moving about on your boat safer.
    2.) Good quality stainless steel rail stanchion bases usually have a rather deep socket and two set screws. Better, but not as good as having through-bolts or welded.
    Hope for the best, but plan for the worst.

  26. #26
    Join Date
    Jul 2015
    Location
    St. Paul, MN
    Posts
    193

    Default Re: Structural steel pipe for rails?

    Stainless fittings also have tight fits which is impossible with hot dip galvanized pipe.

    The set screw type fittings are designed to meet building codes which is a 200# force applied at the top of the rail. You can judge for yourself if thatís acceptable.

    Iím not convinced even hot dipped pipe will hold up when seawater fills up the space between the pipe and stanchion. If nothing else it will rust where the set screw pierces the zinc and lead to rust where itís most critical and hidden.

    I understand the appeal of doing everything yourself but I wonder whatís the point in this case. Fittings are expensive and Iíve never had a problem finding a good welder for steel.

  27. #27
    Join Date
    May 2016
    Location
    Ottawa, Canada
    Posts
    470

    Default Re: Structural steel pipe for rails?

    Quote Originally Posted by J.Madison View Post
    Just to muddy the waters, plenty of boats have no lifelines- and virtually all pleasure boats made today have stainless stanchions held by set screws.
    I have the personal opinion that I'd rather have no lifelines than ones that can't be trusted. I don't want a false sense of security.

    Cheers,
    Mark

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •