Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,291   Posts: 1,535,414   Online: 769
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 12
  1. #1

    Join Date
    Jul 2007
    Location
    London, England
    Shooter
    35mm
    Posts
    113

    Motorised Dish Rockers

    Have a look at this video, and don't forget to turn the sound on, before or after reading on. The video is very amateur but I am learning.

    http://www.youtube.com/watch?v=eJB6QMmmTe9

    I have been meaning to share this idea since I retired 3 years ago and discovered forums. I have never seen such a device mentioned, though for all I know everyone has one. It has been a godsend to me over the last 30 years. The idea is of course not new; there are electric drum processors for colour, and the Paterson orbital motor driven processors; and before that there were rotating and tilting devices to mix blood samples and stop them coagulating in my previous life as a doctor.
    One day in the early eighties I spotted in a surplus store catalogue an advert for geared electric motors, 30 revolutions per minute. A little experimentation with my developing trays suggested this was an OK if not ideal speed for rocking my trays. Keeping it cheap and simple, as I was not sure it would work, I fabricated the devices you see in the video (apologies, video editing not on my CV yet). Melamine covered chipboard held together by screw blocks. A crank attached to the motor spindle, and a 45 rpm record offset by the crank. A little bit of grease where the record runs in the groove of the plastic railing - I thought it would cut through but it never has. The motor runs on 110 volts, hence the transfromer, as UK voltage is 230 volts. A bonus for me is that the box lifts the dishes to chest level; no stooping to see what is going on in the dish.
    I do not use a stop bath, and have found 1 minute in dev and 1 in fix at 20 C quite enough for RC which is all I use routinely, so the Isgus mechanical timer set to its 60 second maximum is perfect; if I want longer I wind it up again.
    I do a lot of run -of-the-mill photography, so printing a 36 frame roll of 35 mm is regular fare, and made much easier by exposing six 5x7 inch sheets, and then developing and fixing them together in 12 x 10 dishes ;if the agitation is being done for you, this leaves hands free to make sure the prints don't bunch and stick together. You can also sip your coffee, take the neg strip out of the enalrger, change the record, whatever. In the video you see me in daylight placing six I made earlier in water; this is purely for illustration as I thought it would make clearer how the sheets slide over one another. For big enlargements in a 20 x 16 dish I normally process one sheet at a time and still use only 2 litres of dev or fix, and help things along with a bit of side to side rocking by hand as well as the motorised back to front rocking. Saves on chemicals and easier to pour out afterwards.
    Only problem for you is finding a powerful geared or stepped motor giving 30 revs per minute; don't know where I am going to find them when these pack up.
    Having said that I have been meaning to share this idea, I did in fact send a video to Nova Darkrooms about 15 years ago; the gist of the reply was that I was 20 years too late!

  2. #2
    resummerfield's Avatar
    Join Date
    Jan 2005
    Location
    Alaska
    Shooter
    Large Format
    Posts
    1,281
    Very nice! This would make an ideal agitation unit for large format film development, using that tray that holds the film sheet—I think it's called a slosher tray.

  3. #3
    GRHazelton's Avatar
    Join Date
    May 2006
    Location
    Jonesboro, GA
    Shooter
    Multi Format
    Posts
    370
    I like it. I'll have to look around for a slow speed motor from Edmund Scientific or some such. One concern - you have highly conductive solutions sloshing around above 230v and 120v wiring. Do you have any splash shield over the motors?

  4. #4

    Join Date
    Jun 2003
    Location
    local
    Shooter
    Multi Format
    Posts
    16,136
    Blog Entries
    1
    Images
    1
    hi youngrichard

    i was the printer for a portrait photographer who was trained in the 20s/30s ..
    and in the darkroom i used we had tray rockers. they were galvanized metal of some sort and ran on a slow motor. it had 3 platforms and they ran continuously all day long
    ( until i unplugged it ) it made quite a racket and was was a great set-up ..

    i wish i could remember more details about it, other than it was a motor, and a cam that ran over 3 metal platforms. i miss all that automation !

    unfortunately ( for me and her ) one of the rockers broke and stopped
    so it was back to hand-work soon after.

    i wish someone made something like this still !

    john
    silver magnets, trickle tanks sold
    artwork often times sold for charity
    PM me for details

  5. #5
    outwest's Avatar
    Join Date
    Aug 2005
    Shooter
    Multi Format
    Posts
    317
    Images
    3
    Barbecue rotisserie motors work well for this.

  6. #6
    Rick A's Avatar
    Join Date
    Mar 2009
    Location
    north central Pa
    Shooter
    Multi Format
    Posts
    5,861
    Images
    32
    Gear reduction motors and a shelf that pivots at the ends. It doesn't require a long rocking motion,1/8inch rise and fall is all it takes to agitate trays. The main thing would be timing the motion so there isn't a huge sloshing action.
    Rick A
    Argentum aevum

  7. #7

    Join Date
    Feb 2008
    Location
    Tucson
    Shooter
    Multi Format
    Posts
    237
    Quote Originally Posted by outwest View Post
    Barbecue rotisserie motors work well for this.
    Good idea!!

  8. #8
    michaelbsc's Avatar
    Join Date
    Dec 2007
    Location
    South Carolina
    Shooter
    Multi Format
    Posts
    2,106
    Images
    5
    Quote Originally Posted by tim k
    Quote Originally Posted by outwest View Post
    Barbecue rotisserie motors work well for this.
    Good idea!!
    The rotisserie motor is an excellent idea.

    another possibility is Hurst gear motors. They pop up on evilBay regularly. You have be specific about the speed since they are available in about 20 configurations. And don't pay too much. Occasionally you'll see some go for almost list price in a bidding war. Others sell for a dollar.
    Michael Batchelor
    Industrial Informatics, Inc.
    www.industrialinformatics.com

    The camera catches light. The photographer catches life.

  9. #9
    Perry Way's Avatar
    Join Date
    Sep 2008
    Location
    San Luis Obispo, CA
    Shooter
    Multi Format
    Posts
    825
    Blog Entries
    13
    Images
    118
    This is a very good idea! (but I am almost totally rotary processing now except for roll films which I have an old habit of inversion agitation, even though I could process them rotary as well.)
    I love the wilderness and I love my trail cameras, all Fuji's! :) GA645, GW690 III, and the X100 which I think is the best trail camera ever invented (to date).

  10. #10

    Join Date
    Jul 2007
    Location
    London, England
    Shooter
    35mm
    Posts
    113
    Quote Originally Posted by Perry Way View Post
    This is a very good idea! (but I am almost totally rotary processing now except for roll films which I have an old habit of inversion agitation, even though I could process them rotary as well.)
    Did anyone ever make one of these? I know there are many alternatives, but something like this gives you time to put the kettle on, change the radio station, whatever.. I couldn't live without it, and dread the day when I have to find a replacement motor!
    Richard

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