is this for Real...Electrical Conduit for Frame building?

Discussion in 'Motorized Bicycle General Discussion' started by shamrock395, Aug 3, 2010.

  1. shamrock395

    shamrock395 New Member

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    OK... I admit I am a newbe here to the forum and I dont want to russel any feathers but i was thinking of building my own frame. The thing is, when I do a search for frame material I keep coming up with posts where people are using "Thin wall Electrical conduit" for there frames. Now I am no expert at frame building but I do alot of electrical work and I am concerned about the strength of thin wall and the welding penitration it is after all "galvivized" and thats not good for the lungs. So I guess my real question is , is there correct tubing to use to put these together? and/or what about using bike lugs for the connections?
     
  2. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    I am going to bump this one up. All I will add is that I used to build ultralights, and you'd be amazed at what people would build those things with....most lived to tell about it, but I doubted the longevity of some of the "designs" I saw flying.
     
  3. Mac

    Mac New Member

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    Funny thing about zinc, smells soooo good when it's welded, it'll also kill ya! I personally wouldn't use electrical stuff except maybe a small brace or something, not the whole bike. there are kits avail from several vendors, here's an example:
    24" Old School Chopper Kit - Cycles U.S. LLC/Choppers U.S.

    Good luck
     
  4. sportscarpat

    sportscarpat Bonneville Bomber the Salt Flat record breaker

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    I wonder if people are refering to ERW or electrical resistance welded tube, and then just guessing the electrical reference means it is conduit. I would never use electrical conduit for a bicycle frame. Besides, all the zinc coating would make for difficult welding. From my experience ERW tubing is pretty good material and DOM is better still.
     
    #4 sportscarpat, Aug 3, 2010
    Last edited: Aug 3, 2010
  5. Kevlarr

    Kevlarr New Member

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  6. GearNut

    GearNut Active Member

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    Do NOT use electrical conduit for making a frame! That stuff is too soft and will fail.
    It was designed to hold and protect wires and be relatively easy to install, nothing else!
    Mild steel tubing is stronger than that steel reinforced bubblegum that conduit is made out of.
    Most suitable tubing is ERW. Mild steel or better yet Chromoly.
     
  7. 2door

    2door Moderator
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    Conduit, (EMT) is okay for exhaust systems but DO NOT try to build a frame from it. I've seen guys build extended front forks from EMT...I would not ride that bike. Thin wall electrical conduit has some uses other than protecting and concealing wiring but bicycle frames are not one of them. Yes, it is easy to bend and make the shape you want but it does not have the strength to hold up to the stresses imposed on it as a bike frame; especially a motorized bike.
    Mile steel will serve you well and if you're a qualified welder, Chrome Moly but leave the conduit to electricians.
    Tom
     
  8. motorbiker

    motorbiker New Member

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    #8 motorbiker, Aug 3, 2010
    Last edited: Aug 3, 2010
  9. Maxvision

    Maxvision New Member

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    Check out a metal supply business, look for the 18 guage welded tubing. It's walls are 1/16th in. thick and comes in wide assortment of sizes.
     
    #9 Maxvision, Aug 4, 2010
    Last edited: Sep 19, 2010
  10. shamrock395

    shamrock395 New Member

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    It was EMT that people were using, and some interesting looking frames, some were real neat . But I am looking to build a drop loop and eather a doner bike will do or like GearNut said some ERW will do best.
    Now about the frame lugs , I keep reading and seeing how people are just welding the frames together (thats how my Columbia is ,or more like brazed). I will be tig welding mine but I will have to say those frame lugs look nice, I just dont know where to get them or if it is even worth the hassle to find them. I trust my welds but -sun of a gun - if 1 fails when I am doing 20 of 25 MPH I will be in a world of pain.
     
  11. donutguy

    donutguy New Member

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    I have a friend that's an engineer and he builds bicycle choppers out of some sort of conduit. I have no idea what type he uses but to my knowledge-he's never had one fail. I think a lot of how a frame performs has to do with how it's designed.
     
  12. motorbiker

    motorbiker New Member

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    It's all here. Henry James Investment Cast frame Components usflg
     
  13. Earthman

    Earthman New Member

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    The fumes from welding or brazing galvanized (zinc coated) material will cripple or kill you. So will using conduit for structural applications. Don't do it.
     
  14. Maxvision

    Maxvision New Member

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  15. 42blue15

    42blue15 New Member

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    Steel loses it somewhat, but not much. Even less if you braze.

    Aluminum will lose a lot though, unless you get the super-low 350F or 500F solder.
    ~
     
  16. OBX Fisherman

    OBX Fisherman New Member

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    If you can build a bike out of bamboo why couldn't you build one from electrical conduit?! Not that I would ride either or consider putting a motor on the thing!!
     

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