Dent in gas tank?

Discussion in 'Motorized Bicycle General Discussion' started by Black_Moons, Jan 2, 2011.

  1. Black_Moons

    Black_Moons New Member

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    Anyone know how to get a large dent outta a gas tank? The 1.8L black one..
    Fell over today and hit a post on the way down... :(
     
  2. Allen_Wrench

    Allen_Wrench Resident Mad Scientist

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    I'm guessing/hoping it's a stock kit tank. First: prepare yourself to possibly buy a new tank. Second: locate or borrow the largest C-clamp you can get, and see if the bottom end (where the screw-down clamp meets) will get into the tank at the backside of the dent. Third: cut a hole in a piece of scrap wood (plywood preferably) that is just bigger than the dent. Put another piece of wood over it.

    With the butt-end of the C-clamp on the inside, put the wood with the hole over the dent, the whole piece of wood over that, and very gently start tightening the clamp. If your dent has any size to it, you may need to use a piece of wood or plastic inside the tank to clamp against, to pull the whole dent out. If this doesn't work, new tanks are pretty cheap. (I've done shade-tree bodywork, can ya tell?)
     
  3. Black_Moons

    Black_Moons New Member

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    Awsome tip! I'll give that a shot, I was planing on welding up some kinda C thing to try and hammer it out from the inside, but a C clamp seems smarter.. :)
     
  4. solokumba

    solokumba New Member

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    If it were me... I would just dent the other side and make it symmetrical again... but that's just me.
     
  5. wayne z

    wayne z New Member

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    Might be a good idea to glue a disc or thick rubber to the foot of the clamp so that the sharp edges of the clamp don't make sharp crescent shaped impressions in the tank. or grind and file the foot to slightly concave shape with edges well rounded. Instead of squeesing the clamp, you may be able to "hammer the dent inside the tank with the clamp body or a welded up dolly.

    Don't expect great results without using bondo though.
     
  6. msrfan

    msrfan Well-Known Member

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    I got a large knee dent out of a Husqvarna tank years ago as a favor to my buddy that crashed it on the first turn of a desert race and punctured his lung. By filling it with water and putting it in the freezer. Came out like new except I should have put a 2X4 in the tunnel as it closed up and wouldn't fit the back bone. Ended up just a flower pot by the time I got it to fit. I had to tell my friend it was not saveable. It should work pretty good on these light gauge tanks. But like allen wrench says, be prepared to get a different one. I think a lot of us have several tanks laying around, maybe even a large one.
     
  7. silverbear

    silverbear The Boy Who Never Grew Up

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    I have several unused stock tanks in Minnesota and would send you one for the cost of postage, but for the fact that I'm in Maryland for the winter. mrsfan is right, there have to be a bunch of them floating around here on the forum for cheap.
    SB
     
  8. fundreamer1

    fundreamer1 New Member

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    Use a heat gun to get it as hot as you can, (you might blister the paint) And then put a piece of dry ice on it, That will cause the metal to shrink where the dent stretched it and sometimes (not always) make the dent reform back to the original shape.
    There are other ways if you don't want to try this one.
     
  9. 2door

    2door Moderator
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    This might work but if you try it, please, please make sure there are NO gasoline fumes in the tank before heating it.
    Tom
     
  10. fundreamer1

    fundreamer1 New Member

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    LOL, I guess I should have said that, I just thought that would be a common sense thing. Thanks for the clarification.
     
  11. Allen_Wrench

    Allen_Wrench Resident Mad Scientist

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    But where's the fun in that. Why, I think it might provide a little extra light to see what you're doing (never mind that your eyebrows are singed off). :)
     
  12. adam valentine

    adam valentine New Member

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    I do paint less dent repair and there are cheaper tools of what i use sold at auto zone for 5 bucks including tax its a flat rounded edge piece of metal and all you do is use slight pressure and work the dent from the outer edge to the inside it will get smaller with minimal pressure use very bright lighting tho so you can see it and don't work too fast unless the paint has cracked, you will not notice that it ever had a dent when you are done, if it has a crease forget it
     
  13. thimmaker

    thimmaker New Member

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    You can also just fill the dent. Sand off the paint in the dent and spray on a coat of self-etching primer (walmart). Let it dry good and start filling with thin layers of Bondo spot putty (walmart). Dry well between coats with a hair-dryer and over fill and let dry completely. Wet sand it to the right contour, prime and paint. Iv'e done 2 old Whizzers and a Cushman Eagle like this and can't tell the difference. And i'm sure the Gasoline doesn't really care if there's a bump inside.
     
  14. kipharley

    kipharley New Member

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    Venice was selling some in the Swap and Shop Thread! Seems to me they were pretty cheap? Kip.
    [email protected]
     
  15. 2door

    2door Moderator
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    I dented a tank a while back, stupid, I dropped it, and needed a way to un-dent it. I made this little swing arm hammer thing that I can insert into the fuel tank and hammer away by manipulating the wire from the outside. It works great on small dents that aren't creased too bad. The weighted thing on the end was just something I found in a junk drawer. It fit on the 5/32 stainless welding rode and even had a set screw to keep it there. I made this one just to have the desired reach for the dent I was working on but one could be made to reach the full length of the tank and adjustable for shorter reaches.
    Tom
     

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