Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 69,887   Posts: 1,520,698   Online: 1115
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 11
  1. #1

    Join Date
    Aug 2010
    Location
    Germany
    Shooter
    Medium Format
    Posts
    20

    Pumps and valves for photo chemistry - which material?

    I'm thinking about building some kind of contraption that will take care of filling/ dumping the chemicals from the development tank.
    I think I can manage the mechanical/electrical side of things. The major Problem is my lack of knowledge about suitable materials that will both withstand and not ruin developer and fixer.
    Are plastics to be preferred to metals, which materials to avoid etc.
    I would appreciate it if somebody could point me in the right direction or share his experiences.

    Movin

  2. #2

    Join Date
    Feb 2008
    Location
    Winnipeg, Canada
    Shooter
    Multi Format
    Posts
    1,301
    Avoid any metals except type 316 stainless. Up to 40C, most any plastics are ok. Nylon, PVC, ABS, styrenes for fabrication. If you are gluing parts, avoid polyethylene and nylon, really tough to glue.
    Bob

  3. #3
    George Nova Scotia's Avatar
    Join Date
    Mar 2010
    Location
    Nova Scotia Canada
    Shooter
    Multi Format
    Posts
    440
    Images
    9
    Fujimoto used iwaki md6 pumps in the cp31 processor. This link should give you some ideas:

    http://www.iwaki.de/produkte/dbpics/...E_0015-12).pdf

  4. #4
    David Brown's Avatar
    Join Date
    Feb 2004
    Location
    near Dallas, TX USA
    Shooter
    Medium Format
    Posts
    3,258
    Images
    5
    Quote Originally Posted by movin View Post
    I'm thinking about building some kind of contraption that will take care of filling/ dumping the chemicals from the development tank.
    Why?

  5. #5

    Join Date
    Feb 2008
    Location
    Winnipeg, Canada
    Shooter
    Multi Format
    Posts
    1,301
    Why not? Makes life much easier when processing films. Some people love building equipment to do stuff. See this set of books. http://www.lindsaybks.com/dgjp/djgbk/series/index.html
    Bob

  6. #6

    Join Date
    Aug 2010
    Location
    Germany
    Shooter
    Medium Format
    Posts
    20
    Thanks for all the suggestions.

    With a little bit of further research I found this extensive chemical resistance chart:
    http://www.buerkert.com/media/COM_Ch...ance_Chart.pdf

    It actually has a category "resistance to commercial products" (p. 22) with photochemistry as one (albeit pretty general) item.
    Valves and pumps that only use materials with complete resistance to constant exposure are pretty expensive.
    Also they seem to be kind of overengineered for my application because they would not be in constant use (like in roller development machines)but only for a very short time.

    I think a system designed only around solenoid valves will fit my needs (both speed and cost). I am currently experimenting with this series of valves:
    http://www.rpesrl.it/product.php?lang=2&cat=10&p=3#3
    Results are promising and the prices are pretty cheap (24€ per valve).

    Movin

  7. #7
    Mike Wilde's Avatar
    Join Date
    Aug 2006
    Location
    Misissauaga Canada
    Shooter
    Multi Format
    Posts
    2,939
    Images
    29
    Look up Wing Lynch. They made a single shot automated film processor. You could process many 35mm or 120 films reels (Paterson type), as well as 8-4x5 at once or even 2 8x10, I think.

    Usually for E-6, but if you are up to making one from scratch you are up to modifying the resistor matrix board to modify the thing to run a B&W process for an 4 series machine.
    They made OEM B&W cards, but they are a fair bit rarer.

    I understand the Wing Lynch 5 series machines were cpu controlled, but I have not played with one of these to see how modifyable the programming is.

    Every small town lab that ever processed e-6 likely has one of these on the verge of being thrown out, now that e-6 film processing volumes have cratered.

    That is how I came by the one I had. It was neat to play with but I did not have the volume to make it worth my while to keep it.
    my real name, imagine that.

  8. #8

    Join Date
    Apr 2010
    Shooter
    Medium Format
    Posts
    4
    There is a chapter on materials in "Handbook of Photographic Science and Engineering" 2nd Edition. IIRC, it covers in detail which metals, plastics, etc. are safe for use in photo-processing equipment. FYI, the book is well worth your time and money. It serves wonderfully as a reference to all things photographic (circa the mid-90s), with extensive references if you need more information.

  9. #9

    Join Date
    Jul 2011
    Shooter
    8x10 Format
    Posts
    2,474
    Any true industrial plastic and pipe distributor should have chemical compatability info in their catalog. But I don't get it either. It is quite difficult to get pumps to fill and drain quickly for even processing. A lot has to do with the design of the drum or tank itself. High-end commercial lab processors are so so common and affordable on the used market right now, or even downright free, that it seems one could simply use one of these outright, or cannibalize one for parts.

  10. #10

    Join Date
    Feb 2012
    Location
    Australia
    Shooter
    Multi Format
    Posts
    45
    But aren't all these commercial machines too large physically, and/or require commercial volumes for processing? I'm very interested in these threads where people design and build things for hobby uses/volumes.

Page 1 of 2 12 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin