Page 6 of 13 FirstFirst ... 45678 ... LastLast
Results 51 to 60 of 130

Thread: Midtone Machines - Automatic Film Processing Machine

  1. #51
    loujon
    Join Date
    Feb 2007
    Location
    Western, PA.
    Posts
    1,645

    Re: Midtone Machines - Automatic Film Processing Machine

    Quote Originally Posted by calebarchie View Post
    Can you elaborate on the light trap? I haven't had any issues.
    It would be a bit of a shame if if you were to make a tank with such minor changes from the phototherm without considering cross-compatibility, there is a pretty high demand for these things. Others would ask sooner or later, just sayin'.
    Plus one! Being a Phototherm owner I agree fully. I would be interested in the ability to buy cross compatible parts if needed.

  2. #52

    Join Date
    Dec 2014
    Location
    Iowa City, Iowa
    Posts
    1,700

    Re: Midtone Machines - Automatic Film Processing Machine

    Question, is there still tooling for Phototherm tanks? Jobo, thank goodness, had the resources to preserve the tooling. As all the old equipment dies there's going to be significant demand for equipment.

    To the OP, design what you want. As long as you aren't using hard tooling changes are easy.

  3. #53

    Join Date
    Sep 2017
    Posts
    112

    Re: Midtone Machines - Automatic Film Processing Machine

    Andrew is probably trying to test the prototype about now. Since we haven't heard back, just thought I'd point out some design oversights that may prevent some headaches;

    You mentioned you light trap design perhaps it is too bulky? It is like for good reason, the input is below the tank to allow even filling and prevent uneven development. Having the input in-line with the reels in your model may create surge marks or uneven dev phenomena across all the rolls as the tank slowly fills to capacity.

    The Phototherm tanks aren't exactly as simple as you may make them out to be. They aren't perfect cylinders there is a slight draft along the length of the tank to assist with drainage but also again to assist with even filling and development. In this case the furthest rolls from the input are closest to the bottom to account for in inlet being on the opposite end. There are ribs on the bottom to keep any leftover chems put until the next full to prevent too much cross contamination.

    There are a few other little things that are not immediately obvious unless you have operated the machines or have a tank in the hand. Again, you will probably find this out as you actually start to test your prototype for development with film and chemicals (not just fluid dynamics) .

    Bests,
    C
    The Container Lab
    www.thecontainerlab.com/blog

  4. #54

    Join Date
    Jun 2019
    Posts
    103

    Re: Midtone Machines - Automatic Film Processing Machine

    Calebarchie, yeah sorry I've been very busy with my day job (https://www.rocketlabusa.com/) and trying to get a friend to assist with the control electronics side. Also trying to get some quote and hopefully some prototype sheet metal parts ordered soon so I can start building up the frame of the machine a bit. Yes I am concerned about surge marks to do with the way the fluid is entering, I originally had a bit of a baffle inside of the tank to divert fluid around but I'm going to try without as it would probably end up foaming the chemicals up. The fluid enters the tank through an oblong hole/slot which should be under the level of the film in the tank and so there shouldn't be any direct impingement onto the film but as you say I'll find out once I start testing and using silicone moulds initially mean that changes are not really expensive to make if I need to.

  5. #55

    Join Date
    Jun 2019
    Posts
    103

    Re: Midtone Machines - Automatic Film Processing Machine

    I know it's been a while since my last blog post but I haven't spent all of the time sitting on my hands, new post is up:

    http://midtonemachines.com/news/shee...-valves-oh-my/

    Sheet metal parts are on the way and I've started life-cycle testing of the pinch valve design I intend to use, to make sure that it's going to be suitable for heavy commercial use (and therefore bulletproof for home use). I also included some of the photos I've been taking recently instead of working on the machine :P all on my Chamonix 4x5 with Ektar and developed at home.

  6. #56

    Join Date
    Dec 2014
    Location
    Iowa City, Iowa
    Posts
    1,700

    Re: Midtone Machines - Automatic Film Processing Machine

    Quote Originally Posted by AndrewBurns View Post
    I know it's been a while since my last blog post but I haven't spent all of the time sitting on my hands, new post is up:

    http://midtonemachines.com/news/shee...-valves-oh-my/

    Sheet metal parts are on the way and I've started life-cycle testing of the pinch valve design I intend to use, to make sure that it's going to be suitable for heavy commercial use (and therefore bulletproof for home use). I also included some of the photos I've been taking recently instead of working on the machine :P all on my Chamonix 4x5 with Ektar and developed at home.
    I see you are looking at thermoforming. I worked for Whirlpool and Maytag in refrigerator engineering, we would run in line and rotary vacuum thermoforming machines that would form in a "double bubble " the fresh food and refrigerator interior cavity liner in one stroke, these units were typically 22 to 25 cubic foot interior volume, about 70 inches tall 33 to 36 inches wide. I started in Amana Iowa in 1994, I still think that and co-extrusion were the most fun part of the operation. I can't remember the cycle time but it seems like we formed a set of liners every 90 to 120 seconds. The biggest co-ex line would extrude ABS sheet around 6 foot wide probably 20 feet / min.
    Maytag built a plant in Reynosa Mexico, Whirlpool bought Maytag/Amana we sold the plant to Fisher Paykel. Small world.

  7. #57

    Join Date
    Jun 2019
    Posts
    103

    Re: Midtone Machines - Automatic Film Processing Machine

    Quote Originally Posted by Duolab123 View Post
    I see you are looking at thermoforming. I worked for Whirlpool and Maytag in refrigerator engineering, we would run in line and rotary vacuum thermoforming machines that would form in a "double bubble " the fresh food and refrigerator interior cavity liner in one stroke, these units were typically 22 to 25 cubic foot interior volume, about 70 inches tall 33 to 36 inches wide. I started in Amana Iowa in 1994, I still think that and co-extrusion were the most fun part of the operation. I can't remember the cycle time but it seems like we formed a set of liners every 90 to 120 seconds. The biggest co-ex line would extrude ABS sheet around 6 foot wide probably 20 feet / min.
    Maytag built a plant in Reynosa Mexico, Whirlpool bought Maytag/Amana we sold the plant to Fisher Paykel. Small world.
    I can only imagine how large and heavy the molds were for that! The vacuum forming production tooling I'm looking at is machined aluminium and I believe they also include heating and cooling in the mold to assist cycle times (not that I believe that will be an issue for my small volumes).

    I've also just done a test of the pump filling and draining the developing tank, I can fill the 4-reel tank in 12 seconds which I think is well fast enough to avoid uneven development. I will have to look at improving the drainage however as it isn't very efficient at getting the dregs of the chemicals back out again.

    Also pinch valve is now up to 7000 cycles and still going strong.

  8. #58

    Join Date
    Sep 2017
    Posts
    112

    Re: Midtone Machines - Automatic Film Processing Machine

    Position and slope!
    The Container Lab
    www.thecontainerlab.com/blog

  9. #59

    Join Date
    Dec 2014
    Location
    Iowa City, Iowa
    Posts
    1,700

    Re: Midtone Machines - Automatic Film Processing Machine

    Quote Originally Posted by AndrewBurns View Post
    I can only imagine how large and heavy the molds were for that! The vacuum forming production tooling I'm looking at is machined aluminium and I believe they also include heating and cooling in the mold to assist cycle times (not that I believe that will be an issue for my small volumes).

    I've also just done a test of the pump filling and draining the developing tank, I can fill the 4-reel tank in 12 seconds which I think is well fast enough to avoid uneven development. I will have to look at improving the drainage however as it isn't very efficient at getting the dregs of the chemicals back out again.

    Also pinch valve is now up to 7000 cycles and still going strong.
    Yes there's temperature control in the molds, it's been many years back since I was directly involved. The foam insulation between the inner and outer walls required massive tooling cores and outer support structure, you can lift a truck off the ground with polyurethane foam. As I recall most of our aluminum molds and foam cores were made in Italy. Amazing craftsmanship. Today, as with injection molding tooling, I suspect China is a major player.

    12 seconds sounds great to me, it takes me that long to pour solutions into my Jobo with the lift.

    We used "Thermolators" to maintain foam core temperature, would heat at beginning, then chilling (heat pumps) would come on to take the enormous amounts of heat out of the foam tooling from the exotherm. Every 3 1/2 minutes one fixture produced a foamed cabinet. With 40-50 fixtures you could make a lot of big refrigerators.
    Looking forward to seeing further progress.
    Best Regards Mike

  10. #60

    Join Date
    Jul 2013
    Posts
    264

    Re: Midtone Machines - Automatic Film Processing Machine

    Quote Originally Posted by AndrewBurns View Post
    I can only imagine how large and heavy the molds were for that! The vacuum forming production tooling I'm looking at is machined aluminium and I believe they also include heating and cooling in the mold to assist cycle times (not that I believe that will be an issue for my small volumes).

    I've also just done a test of the pump filling and draining the developing tank, I can fill the 4-reel tank in 12 seconds which I think is well fast enough to avoid uneven development. I will have to look at improving the drainage however as it isn't very efficient at getting the dregs of the chemicals back out again.

    Also pinch valve is now up to 7000 cycles and still going strong.
    12 seconds is the time I use on my Jobo from the start of lifting the handle on the lift to pouring in the next solution.


    Sent from my iPhone using Tapatalk

Similar Threads

  1. B&W PAPER processing machines
    By DrTang in forum Darkroom: Film, Processing & Printing
    Replies: 10
    Last Post: 30-Jul-2015, 11:29
  2. Agfa Curix 60 Processing Machine
    By muffin in forum Darkroom: Film, Processing & Printing
    Replies: 1
    Last Post: 11-Jun-2012, 04:29
  3. X Ray Machines at Airports and Fogged Film
    By ki6mf in forum Location & Travel
    Replies: 7
    Last Post: 29-Sep-2008, 11:55
  4. machine for processing negatives
    By mo in forum Darkroom: Film, Processing & Printing
    Replies: 2
    Last Post: 30-Oct-2001, 07:35
  5. Loaded Sheet Film and Airport Carry On X-Ray Machines
    By Andre Noble in forum Cameras & Camera Accessories
    Replies: 31
    Last Post: 29-Aug-2001, 20:34

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •