HOPE RA 4 rack rebuild: help!

Discussion in 'Darkroom Developing and Printing' started by JacktheCat Turkey, Jul 21, 2003.

  1. Hi gang,
    O.K. so call me a masochist, but as the new darkroom technician at a
    public university with a vastly under funded photo program it is my
    responsibility to nurse our HOPE RA2016 along.

    That upkeep now involves the inevitable rebuild of the racks.

    While the thermoplastic rollers are o.k. the retainers, springs, spring
    clips and plastic rack-side roller bearing inserts are way overdue for
    replacement. With over 10 years of service I suspect most of the
    aforementioned parts have never been replaced.

    Following a through cleaning, I have done the "exploratory" surgery on
    the DEV rack and the three BLIX/WASH racks to discover a degree of
    "slop" in some rollers. some gears are worn, springs missing, and a
    small sheet of paper marooned around a roller deep in the first wash
    rack.

    I need to know the "tricks" of rebuilding these racks without getting in
    too deep.

    Also, which gears are the ones that get lubed and with what?

    What are the essential spare parts to always have on-hand?

    Who do you use as a vendor for supplies?

    Do any of you have the new Kreonite part #'s that replaced the old HOPE
    part #'s?

    Your experience and wisdom are appreciated.

    Jack
     
    JacktheCat Turkey, Jul 21, 2003
    #1
    1. Advertisements

  2. JacktheCat Turkey

    Mike King Guest

    Used to do this for a living, ran a mini-lab with a couple of Hope
    processors, so here goes.

    The Hope bearings are made out of various plastics (nylon, Delrin, etc.) and
    are intended to be lubricated by the solutions they are submerged in. The
    bearings that will wear the most are the ones above the surface of the
    liquid, but part of your start up procedure each morning is to wet the top
    bearings and rollers thoroughly with warm water before you start the
    machine. This lubricates the bearings, and rinses off any chemical
    crystallization that may have occurred overnight. Bearings and retainers
    were made out of several materials depending on location but the colors are
    also different, so always replace a blue retainer with a blue retainer, etc.
    Don't assume that every roller will have a spring, you really need a set of
    schematics with exploded diagrams to figure out if anything is missing. The
    bearings that wear the most are the ones in the top of the racks, less
    lubrication and more stress, and the ones in the very bottom of the rack
    where the prints have to "turn-around" and go back up the other set of
    rollers.

    Most Hope racks are "zero-torque" meaning that, if set up correctly, you can
    turn the racks with one finger, if you have to force it something is not
    right.

    You should be able to contact Hope/Kreonite for manuals and diagrams. Hope
    this helps.
     
    Mike King, Jul 22, 2003
    #2
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.