Jobo 2800 series drums diameter

Discussion in 'Darkroom Equipment' started by rob champagne, May 30, 2008.

  1. rob champagne

    rob champagne Member

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    Can anyone tell me the inner diameter of jobo 2800 series print drums?

    Also the useable length of a 2830 drum, the useable length of a 2840 drum and the useable length of a 2870 extension model.

    I realise there are defined uses for these drums giving paper sizes but it would be useful to know the real dimensions as I may not be using standard paper sizes and we have some different paper sizes in the UK.

    The diameter is the most important for me.

    Thanks.
     
  2. Nick Zentena

    Nick Zentena Member

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    Inner? It takes a 2500 type reel. The tanks are really aimed at metric paper and the US sizes are the next lower ones. I hope that makes sense.
     
  3. rob champagne

    rob champagne Member

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    I want them for printing so reel size is not important. The diameter is for working out circumference so I know the maximum paper size that will fit.
    A 2500 tank has a 14cm diamter so circumference is 17 inch. I guess the 2800 will be the same if it takes the same size reels.

    Are there ridges down the inside of the 2800 tanks like there are on the 2500 tanks or is the inside smooth?
     
  4. Nick Zentena

    Nick Zentena Member

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    The ridges are a feature of the 2800 tanks. Three together and one more on it's own. The smooth tanks are actually a 2500 feature. It's really the only difference between the two. The 2800 need the ridges for multiple smaller sheets.
     
  5. rob champagne

    rob champagne Member

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    the ridges may be OK for smaller sheets and RC paper, but what about FB paper which becomes very soft when its wet. Would those ridges leave marks on 20x16 paper?
     
  6. Nick Zentena

    Nick Zentena Member

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    I don't know I only use the drums for colour. I think I remember Jobo saying they were okay for fibre but that's just memory. They don't scratch film. You'll find many use the same drums for large sheet film.
     
  7. Nick Zentena

    Nick Zentena Member

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    BTW the ridges would be the back of the paper. Would marks on the back matter?
     
  8. rob champagne

    rob champagne Member

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    well they could stretch the emulsion and that is likely to show up in some toning processes. I may just be being paranoid about it but if others have experienced no problems then I'll have to try and see what happens.
     
  9. grahamp

    grahamp Subscriber

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    I have done 20x16 Ilford Multigrade Warmtone in a Jobo print drum without any marks. The bigger risk, in my opinion, is creasing the paper getting it out when wet. I did a pre-soak, develop, stop, fix, rinse cycle on a manual roller base. My CPE-2+ cannot handle anything above 11x14. The only reason I do this is because my space is tight for tray processing at this size, and the drum is easier for a couple of sheets. I wash my 20x16 in a Versalab 11x14 washer with a substitute insert.
     
  10. Mick Fagan

    Mick Fagan Subscriber

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    The 2840 will take a maximum print size of 30x40cm or in USA/UK language, 12"x16"

    Mick.
     
  11. Lopaka

    Lopaka Member

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    The 2800 and 2500 are identical in diameter. Some of the most recent manufacture are all 2800, just some have 2500 labels. The same lids fit on both. The only difference in the lid is the removable inner funnel which is different for film vs prints. I have done 16 x 20 fiber and had no issues with the ridges.

    Bob