Brass Tubing Exhaust?

Discussion in 'Motorized Bicycle Welding, Fabrication and Paintin' started by Tinsmith, Apr 2, 2012.

  1. Tinsmith

    Tinsmith Member

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    I found a piece of brass tubing at work. Looks to be about 1 " with about 1/16" wall and pretty rigid. Could I fashion an exhaust for the 49cc HS with a regualr old conduit bender? Thanks for any input
    Dan
     
  2. 2door

    2door Moderator
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    Dan,
    I'm afraid you're going to have problems bending that brass. Even the old packed sand trick might not keep it from kinking. There is/was a product called Cerobend that might work. It was a low temp lead based alloy that melted at about 200 degrees. You fill the tubing with it in a molten state and allow it to cool then bend the tubing and then heat it in hot water and the Cerobend would run out leaving a good, kink free bend.
    A member posted a link to Cerobend a while back but I can't find it now. Maybe he will see this and repost where it can be obtained. Good luck.
    Tom
     
  3. thegnu

    thegnu New Member

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    thats a cool lil tip to know, but I would think brass would be too brittle to take much of a bend if any at all .
    Gary
     
  4. silverbear

    silverbear The Boy Who Never Grew Up

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    I hope you can find a way to do it, Dan. It sure would look good with your old (new to you) brass horn. (This is new to Dan's bike and is a lot louder than I thought it would be.)
    SB
     

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  5. Ibedayank

    Ibedayank New Member

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    I find that bending Brass is like trying to bend castiron.
     
  6. rustycase

    rustycase Gutter Rider

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    Aside from problems working it initially, it seems to me that the repeated heating/cooling process would make the tube very brittle, just as copper. Possibly worse!

    Duh... now that I actually try to think about it, shell casings for my rifles split and crack after just a few cycles. Of course that's more heat, and pressure, but a cycle engine is going to introduce a lot of vibration into the mix...

    Gosh brass pipes would LOOK neato, though! :)
    rc
     
  7. Ibedayank

    Ibedayank New Member

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    wonder if they make a brass colored hi temp paint
     
  8. thegnu

    thegnu New Member

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    Why not look into brass electro plate ? best of both worlds make it in steel an plate it
     
  9. Tinsmith

    Tinsmith Member

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    Thanks for all the input guys. Tom, I'm aware of the Cerobend process, but I'm skeptical of being able to bend it also. I was just hoping one of you wizzards would say it could be done. Electroplating is an interesting idea and I must say I've never tried bending cast iron, but I'll let you all know when I do. It's nothing that is bothering me I just thought since I had the material it might be something to try. Thanks everyone.

    Dan
     
  10. Mr.B.

    Mr.B. Well-Known Member

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    Brass will bend easier if you anneal it first by heating it cherry red. If it applies there’s actually plenty of online info for bending small tubing.

    However looking to history I don’t recall ever seeing a brass exhaust system? I suspect there must be a good reason for that...? ? ?

    -Kirk
     
  11. 2door

    2door Moderator
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    That's the stuff. I watched it being used by some Air Force types. They had it in a metal container that was full of hot water with the alloy in a molten state. They would dip the tubing into the melted metal, fill the tube and cap the ends with rubber plugs then dip the tubing in cold water. The tubing then became like a solid rod that could be bent into any shape. After the bending process the tubing was again submerged in the 'hot vat' and the alloy would melt and could be poured out.
    I saw them bend steel, aluminum and stainless steel tubing but never saw brass being bent. Not much brass tubing on airplanes.

    I wouldn't begin to know how you would calculate the amount needed. It would be based on the length and diameter of the tubing you're trying to bend and the volume of a one pound ingot.

    Thanks, Moon.

    Tom
     
  12. moonerdizzle

    moonerdizzle New Member

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    Not a problem. I keep wanting to try cerrobend, but never buy it. I do like to use sand to bend tubing. Im thinking of trying some Aluminum oxide blasting media we got at work, i think since its dry and would compress good it would work pretty good for bending material.
     
  13. halfevil333

    halfevil333 New Member

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    One of the few reasons I actually like being here in Fl....the sand is EVERYWHERE and super fine.
    If you fill the tubing first with water, then displace it all with the sand, you get MUCH BETTER pack in the tube, and therefore a better bend. Plus, this method allows you to heat just the section being bent, and not much beyond that...better for hands, better for bends.
     
  14. moonerdizzle

    moonerdizzle New Member

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    I was taught never to use wet sand to bend tubes because when you seal the ends and heat it the moisture boils off and pressurizes the tube. I would rather not be bending a pressure vessel or have one of the ends blow off at me or some one near me. i just pour sand in, pack it down with a rod alittle smaller than the tube im bending, pour some more and repeat.
     
  15. 2door

    2door Moderator
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    I've always heard the same about wet sand and a sealed tube. Steam under pressure can do some amazing things. Mixing water and heat might provide you with what could essentially be a 'pipe bomb'. Be careful!

    Tom
     
  16. rustycase

    rustycase Gutter Rider

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    lol

    I wish I could find the vid on the guy making an xpansion chamber using a pressure washer.
    U guys would really enjoy that!
    rc
     
  17. Tinsmith

    Tinsmith Member

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    Thanks for all the discussion guy!
    Dan
     
  18. thegnu

    thegnu New Member

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    I have seen that 1 , I wouldnt be any where near that just looked like a bomb with schrapnel an all that jaz .
     
  19. moonerdizzle

    moonerdizzle New Member

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    i think i seen that once, i looked for it again, but i couldnt find it. i also seen a video of a guy who used water and froze it to expand the metal for his expansion chamber.
     

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