Use of Jobo Expert Drums, filling & emptying

Discussion in 'Darkroom Equipment' started by Ed Bray, Dec 2, 2012.

  1. Ed Bray

    Ed Bray Member

    Messages:
    348
    Joined:
    Nov 23, 2011
    Location:
    Plymouth, UK
    Shooter:
    Multi Format
    I received my first Jobo Expert Drum on Friday, a 3010 which can do up to 10x 4x5 sheets or (off use by some) 5x 5x7. As I am planning on using Pyrocat HD at 1.2:1:100 which states that a minimum of 75ml is needed per 4x5 sheet (or equivelent). This would give me a total of 750ml if using a full drum of 5x7 or 4x5.

    Now my concern is how best do I get such a large volume into the drum to try to maintain even development? As the drum does not appear to me to be very quick filling. If I fill the drum in an upright position, surely the part of the negatives closest to the bottom of the tank will start to develop sooner than the parts nearer to the top of the tank as the developer will pool in the chambers by gravity during the filling operation.

    Should I try to make some sort of tube (which I can locate one end into the filling hole) with funnel attached to the other and fitted to a stand to which I can pour the developer into whilst the drum is rotating?

    Or is there another method that you use?
     
  2. Sirius Glass

    Sirius Glass Subscriber

    Messages:
    20,724
    Joined:
    Jan 18, 2007
    Location:
    Southern California
    Shooter:
    Multi Format
    I am using a Jobo CPP2 with a lift and since the drum is turning when the chemicals are poured in and emptied, I have had no problems with uneven development. I have not tried hand inversion, which it sounds like your are planning on doing, so I cannot comment on that.
     
  3. CatLABS

    CatLABS Subscriber

    Messages:
    1,476
    Joined:
    May 20, 2011
    Location:
    MA, USA
    Shooter:
    Large Format
    Most Expert drums users who do not use a a Jobo processor with a lift just fill the tank up as needed and start the process.

    The funnel allows for fairly fast filling (you can test with water) and you should have no problem.
     
  4. cowanw

    cowanw Member

    Messages:
    1,303
    Joined:
    Aug 29, 2006
    Location:
    Hamilton, On
    Shooter:
    Large Format
    I was worried about the same thing, but it has not been a bother to me. I prewet and have filled the tubes with the required water, and then the concentrated developer (so then active pouring time is just for 100cc's) (pour with the tube on a slant so a water bell doesn't slow things down). I have also I develop for 10 minutes and haven't seen any problems. I have also done a 600 cc water then 600 cc developer mix and nothing is different.
    I am using 1050 cc water and am mixing 150 cc liquid developer in this.
    Some time in the past a member posted his invention for filling while turning but I cant find it.
     
  5. Ian C

    Ian C Member

    Messages:
    722
    Joined:
    Feb 8, 2009
    Shooter:
    Large Format
    The Jobo Expert series of drums are all cog-drive-only, because they are intended by Jobo to be used exclusively with a cog-drive lift unit. The solutions are introduced into the drums while they’re horizontal and rotating. These drums are not intended to be filled upright. If you do so you will likely have problems with eneven development.

    The lift unit of the manually operated processors fill the drum via an integral funnel and tube that conducts the solution into the drum as it rotates. The automated versions use air pressure to transport the solutions into the tubing and then into the drum. These drums are not intended for hand filling and emptying and there is no provision for attaching a coupling magnet on the tank bottom, which is the other Jobo rotation option on its processors that are not equipped with a lift unit.
     
    Last edited by a moderator: Dec 2, 2012
  6. ChuckP

    ChuckP Subscriber

    Messages:
    655
    Joined:
    Jan 8, 2003
    Location:
    NW Chicagola
    Shooter:
    Multi Format
    You should be able to purchase a funnel with tube attached pretty easily. Try an auto parts store. I use the Expert on a Unicolor motor base and fill with the funnel and tube while the drum rotates. It's easy enough and just the way I always do it. But as other have indicated just pouring it in without rotating seems to work fine.
     
  7. Ed Bray

    Ed Bray Member

    Messages:
    348
    Joined:
    Nov 23, 2011
    Location:
    Plymouth, UK
    Shooter:
    Multi Format

    Thanks all for your thoughts.

    I am aware that the Expert drums are designed to be used on a processor with a lift, but many sheet film users use them successfully on a variety of rotation motors and some even hand roll the drums.

    I will be rotating my drums on a Unicolor Rotating Base and therefore need to find the best means of filling the tank to avoid uneven development.

    As it happens, I have just succcessfully filled the drum with the required amount of water whilst rotating using a 1" bath overflow hose fitted to a funnel at one end and a washing machine waste 90 degree adapter at the other. The washing machine adapter fits into the central hole of the lid with about 0.5mm clearance so does not bind whilst rotating. I have just tried it out and the tank fills nicely with no spillage whatsoever. I just have to find something to mount it to now to allow it to stand independantly.
     
  8. ic-racer

    ic-racer Member

    Messages:
    7,514
    Joined:
    Feb 25, 2007
    Location:
    Midwest USA
    Shooter:
    Multi Format
    Those Expoert drums were made to be used with the lift and fill while spinning. For hand inversion processing of 4x5 I have used the 2500 series drums with success. There is plenty of room in those tanks for dilute developer solutions.