Jobo Explosion

Discussion in 'Darkroom Equipment' started by Allen Friday, May 4, 2006.

  1. Allen Friday

    Allen Friday Member

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    Tonight I did something I have never done before. I ruined two sheets of 12x20 film in a jobo. I developed the film in the 20x24 print tube. Everything went fine until I popped the top. I use the foot pump to get the top off. I did everything like I normally do, except that I put the tube on a stool when filling it with air. The seat of the stool is a cane seat and has some spring to it.

    I put my hands on the top of the tube to keep it from shooting upward. When the top shot off, I ended up pushing the top down into the tube sideways. The top scratched both sheets of film. The sheets are now residing in the circular file.

    Live and learn.

    Allen
     
  2. Robert Hall

    Robert Hall Subscriber

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    Well, that is one thing I've yet to do. I will file that one away.

    Better luck next time.
     
  3. jeroldharter

    jeroldharter Member

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    Sounds like you had to apply alot of pressure to get the lid off. I have used the same drum and the 3010. I apply a few partial breaths from the foot pump and the lid gently poofs open. Maybe you are jamming the lid on too tightly or just had bad luck this time.
     
  4. Peter De Smidt

    Peter De Smidt Member

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    I'm not the original poster, but I have the same problem. My older 5x7 expert drum pops off easily with a few pumps of air. My newish 8x10 expert drum needs to be pressurized to dangerous levels before it'll pop off. Both lids are put on with the same amount of pressure, namely just enough to ensure that they are seated squarely. I've been thinking of lightly polishine the inside lip of the the lid, but I'm hesitent given how much these drums cost.
     
  5. John Koehrer

    John Koehrer Subscriber

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    Why not just cover the cap with a bath towel which should keep it from hitting the ceiling? Or a bungee buddy which is used to hold a helmet on the back of a motorcycle instead of keeping it on your head where it should be.
    Bungee buddies can be found a most motorcycle dealers or online.