Any one know the strength of 1" EMT (Conduit) ? Making homemade guard rails for Scaffolding

Photowhit
Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
Okay, I'm cheap, follow me long enough and you'll find me picking up broken tie downs from the side of the highway for the hooks! Or lugging home broken cedar fence, or dehydrating 3 bushels of apples while they're cheap (Now...lol)

So, I have a fear/respect for heights. I'm getting around to finishing some solar projects and I'm too cheap to buy Scaffolding Guard rail set up, particularly since I can only setup one long side for most of the jobs.

http://www.homedepot.com/p/MetalTech-7-ft-x-5-ft-Scaffold-Tower-Guard-Rail-System-M-MG507K/206733478

This appears to just be lighter than 1" conduit, (16 gauge 1" OD tubes) So I've purchased a single 1" conduit (Conduit is 1" inside) and drilled (I know this weakens it) for mounting in the scaffolding tubes and drilled some 5/16th inch holes for Snap Pins and drilled out holes in some 2x4's as cross members/rails, at @18 inches and 32-36inches, I eye balled it. It's job is just to keep me from stepping off the scaffolding. but I'm guessing it would support 100lbs.

I can post some pictures if anyone would like, it sounds a bit confusing, but I'm using the conduit is posts and 2x4's as rails, sitting on the snap pins which are about 3 inchs long.  There are no spec's as to what the guard rail will hold, but I'd guess there is some OSHA guild lines...
Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
- Assorted other systems, pieces and to many panels in the closet to not do more projects.

Comments

  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,730 ✭✭✭✭✭✭
    The thickwall EMT I use 1.5", is very close to the snow load/wind spec of 1.5" water pipe which is generally specified for the ground mounts I use when I do not need tracking.
     I would not use the thin wall!  Hope this helps
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • softdown
    softdown Solar Expert Posts: 3,812 ✭✭✭✭
    Iron plumbers pipe may be the strongest pipe for the dollar? Just guessing...

    I think grey PVC may be stronger, in some respects, than EMT.
    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • jonr
    jonr Solar Expert Posts: 1,386 ✭✭✭✭
    My rough calculations suggest nowhere close to being stiff enough.  1.5" pipe looks minimally acceptable.

    I am available for custom hardware/firmware development

  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    1 1/2" steel pipe is what the scaffolding is made of... It won't fit within the pipe.

    I'm not trying to build scaffolding, I live near a nuke plant and have spoken to the fitters who build the massive multi story scaffolding from bare pipe and knuckles(?). I have scaffolding, just trying to figure out the strength of the guard rail I built.

    I do think regular galvanized steel pipe would be plenty strong even with the drilled holes, to be a heavy load bearing structure, I'm sure I could hang on it. The only thing available is black pipe which would not fair well living outside.

    It might surprise people that the braces for scaffolding have the same spec's as 3/4" conduit! ...but the max load is very minimal.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • softdown
    softdown Solar Expert Posts: 3,812 ✭✭✭✭
    I've seen plumbers steel pipe, used in restaurants, to keep customers where they are supposed to be. With the tee's and accessories, you can easily build what you want. You may be able to slide thin wall pvc over it for weather-proofing...not sure.
    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Bracing may only be used in tension. And you can use cable and such too.

    Only need larger diameter/thick wall piping if used in applications to resist bending.

    If you put the railing under tension, then thin wall running/cable can be used.

    If the railing would collapse from side loading, then thick wall pipe would be better.

    -Bill "not a civil engineer" B.
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • softdown
    softdown Solar Expert Posts: 3,812 ✭✭✭✭
    Sometimes it is very hard to beat treated 2"x4"(s).
    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • littleharbor2
    littleharbor2 Solar Expert Posts: 2,039 ✭✭✭✭✭
    How about running a length of rebar inside the conduit?

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric,  460 Ah. 24 volt LiFePo4 battery bank. Plenty of Baja Sea of Cortez sunshine.

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Pipe would be stronger per unit weight if you are looking at bending resistance.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • jonr
    jonr Solar Expert Posts: 1,386 ✭✭✭✭
    > 1 1/2" steel pipe is what the scaffolding is made of... It won't fit within the pipe.

    So it might be possible to create a solid steel pin that connects the 1.5" scaffolding to a 1.5" post?  Or take what you have, set it a few feet above ground level and throw your weight at it.  I expect that how much a railing flexes is important to maintaining balance.

    I am available for custom hardware/firmware development

  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    I'm good, it works fine, when researching the strength, I found a welding site where a guy made scaffolding out of 16 gauge square steel made me for more comfortable. I'm done with the needs for guard rails. I'll reset up on the short side tomorrow and will post a picture.  I might make some out of heavier gauge steel pipe later.

    FWIW, I did think about inserting some 3/4" conduit inside to stiffen, but once I got my hands on the 1" I found it pretty strong/heavy (and lining up multiple holes would be a pain). I know the risk/weakest point is the holes drilled and tearing out. If I replace them I'll do a test. Mostly it's not intended to be load bearing, which I think the same goal as the company made hand rail. I do like having the 2x4 rail, set my drill on it several times.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Here are some photos of the guard rail, FWIW...

    It's on the low end of the array, so I really don't need them.

    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    You could always use sticks like they do in Laos.......just joking.  Have seen bamboo used in Hong Kong upwards of 30 stories, it's said they trust it over steel.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • softdown
    softdown Solar Expert Posts: 3,812 ✭✭✭✭
    Bamboo is really strong. That would work fine for Photowhit.
    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    The thickwall EMT I use 1.5", is very close to the snow load/wind spec of 1.5" water pipe which is generally specified for the ground mounts I use when I do not need tracking.
     I would not use the thin wall!  Hope this helps


    Am a bit late to this,   BUT,  EMT IS EMT,  IMC IS IMC,  and RGD (Rigid) pipe IS RGD.   EMT is not threaded,  IMC and RGD pipe IS threaded,  as supplied in 10' lengths:

    http://www.falsonsupply.com/Catalog/123FS.pdf

    FWIW,   Vic

    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,730 ✭✭✭✭✭✭
    edited November 2016 #17
    Definately but we can't always be as sharp as we want here. I did cover myself somewhat by saying the "thick wall" pipe is what you want for a mount. It is the same as schdule 40 water pipe which is often speced for ground mounting solar from my supplier Pro Solar.
    I think bamboo would really be hard to spec in a 50 service life...
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    heck guy's the project's done and scaffolding down. My guess is that a 300lb guy falling 4 and a half feet against it would be retained on the scaffolding. I suspect I'll even replace it with heavier stuff, likely ridged pipe (RGD I've learned) and test the conduit for you at some later date.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,730 ✭✭✭✭✭✭
    Did you need any bamboo?
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    No I managed without. Maybe when I'm home for Turkey day in Florida. Seriously it's great stuff and resilient. Likely a better choice than a 2x4 for rails...

    ...though setting a drill on it will take some talent!
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    Some pretty good videos on YouTube show how they build  bamboo  scaffolding, no drilling required.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.