Combi-Plan & Microwave

Discussion in 'Darkroom Equipment' started by CPorter, Feb 13, 2008.

  1. CPorter

    CPorter Member

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    I usually warm solutions in another safe container but I was wandering if any combi-plan tank users know if these tanks are microwavable safe for warming solutions?

    Thanks
    Chuck
     
  2. Mike Wilde

    Mike Wilde Member

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    If it is bakelite its ok

    I pour a litre of developer into an old 4x5 developing tank, and warm them together in the microwave. The bakelite seems to take this just fine. I go in 20 second balsts, and then measure where I am at after each blast of microwave energy.

    The 4x5 tank has a pretty big thermal mass. I found that I would ge the developer to the right range of temperature on its own, then it would be cooled by the temperature of the tank ( my darkrrom is in the basement, and sits around 17C this time of year, unless I am in there.)
     
  3. Lee L

    Lee L Member

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    I've never seen any info on the type of plastic used in the Combi-Plan tank, and the lid and tank body are different materials. To me the tank "feels" like it's some form of styrene, but that's a wild guess. Styrene will deform when heated, but you may not be reaching temps that would cause that. Short of asking the manufacturer or testing with your own tank, I don't think you'll find any guarantee that microwaving a Combi-Plan is a good/workable idea.

    Lee
     
  4. Trevor Crone

    Trevor Crone Member

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    It probably would be ok but most domestic microwaves are not very accurate with regard to temperature setting. What I use the microwave for is to just warm the water I use to mix the film dev. to the right temperature. I usually do this in a few second bursts. If I go too high I simply mix in more cold water. If you over heat the mixed developer its a little more difficult to bring it back down, put it in the fridge or cold water bath etc.

    I've just tried my Combi with a litre of distilled water in my microwave and it went from 18.8*C to just over 21*C (my normal film dev. temp) in 16 seconds, highest setting. The tank wasn't even warm as you would expect for this short time period.
     
    Last edited by a moderator: Feb 14, 2008
  5. CPorter

    CPorter Member

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    Thanks for the responses.

    Trevor, thanks for risking your tank for my info :surprised:. I didn't have the nerve to risk my own since the darn things are kind of expensive. Good to hear that it went ok and your tank didn't warp in the small amount of time you gave.

    The reason I asked the question was because I poured one part distilled water and one part d-76 in the tank without first warming it in another container first, like I usually do. I thought I would warm it in the combi-plan, but just before I turned on the microwave, it occurred to me that it could be a $75 mistake!

    Thanks
    Chuck
     
  6. Trevor Crone

    Trevor Crone Member

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    My pleasure Chuck; it was a calculated risk. I couldn't see the tank comming to any harm in such a short space of time.
     
  7. fschifano

    fschifano Member

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    I don't think that any harm will come to your tank in the brief period and low temperatures involved here, but I still think you're nuts. If you need to raise the temperature of the solution in the tank, simply immerse it into a warm water bath. Everything, including the tank, comes up to temp quickly and easily.
     
  8. JBrunner

    JBrunner Moderator Staff Member Moderator

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    Is this a microwave dedicated to photographic uses, or are you cooking your burritos in it when its not nuking D76?:wink:
     
  9. CPorter

    CPorter Member

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    Weeeellllllllll, uhhhh, ummmmm. Maybe.
     
  10. CPorter

    CPorter Member

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    My solutions can be pretty darn cold when I decide to develop. In plastic tanks the temp does not come up quickly enough for my liking and a few seconds in the microwave does no harm to give the temp a boost and it gets me done with the kitchen considerably sooner. I never take the temp beyond 68 degrees. It goes to the warming bath for the last two or three degree movement up to 68. What's nuts about that? :tongue:
     
  11. Pragmatist

    Pragmatist Member

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    You risk degrading the chemicals that are in solution--microwaving photographic chemistry is not a good idea.