Another DIY Rotary Film Processor

[pound]

I finally put this project together after moving on to shooting 8x20 and could not bear manually rotating the drum.
Basiclaly it is made up of a roller base with 4 Rigid Wheels, a motorized arm with 2 wheels and a Arduino Uno box.
More details on the parts and components at http://sgwetplate.com/2016/10/diy-ro...ilm-processor/




The roller base with 4 Rigid wheels
I connected the 2 pieces of plywood using 2 brass rails (they were from a forsaken camera project). They are locked down using 1/4" bolts and nuts. This will allow me to adjust the distance between the 2 rolls of wheels for catering to drums of different diameters. At this point the drum should rotate smoothly and evenly by hand.


The motor and the shaft coupler
For now I am using a 12V 30 rpm motor. To mount the 3/8" threaded rod (again another piece I have sitting around) , I use a flexible shaft coupler which has a one 6mm hole what will fit the motor shaft while the other end is a 10mm hole that fit the 3/8" rod.

[B.S.Kumar]

Very neat and simple. Good job!

Kumar

[Graham Patterson]

That's an elegant solution for a dry roller. Do you get much slippage from the skate wheels? These little microcontrollers and the interface boards make motor control so much easier these days.

[pound]

That's an elegant solution for a dry roller. Do you get much slippage from the skate wheels? These little microcontrollers and the interface boards make motor control so much easier these days.

Thanks!
The wheels has good contact with the drum. The drum tends to move forward(to the left as seen in the first photo) as it got rotated so I will have to get a barrier on the left to make sure it does not go too far off.

[Greg]

Thanks!
The wheels has good contact with the drum. The drum tends to move forward(to the left as seen in the first photo) as it got rotated so I will have to get a barrier on the left to make sure it does not go too far off.

Experienced that same very gradual movement of the drum. Fortunately it was always in the same direction, so I glued a piece of thin plastic to one of the insides of my darkroom sink. Place my Unicolor roller base with the JOBO drum's base a 1/4 of an inch away from the plastic. As it spins, the drum slowly creeps to be in contact with plastic which stops it from rolling off the Unicolor roller base. After dozens of time doing this, I have yet to see any wear on the bases of my JOBO drums.

[pound]

Experienced that same very gradual movement of the drum. Fortunately it was always in the same direction, so I glued a piece of thin plastic to one of the insides of my darkroom sink. Place my Unicolor roller base with the JOBO drum's base a 1/4 of an inch away from the plastic. As it spins, the drum slowly creeps to be in contact with plastic which stops it from rolling off the Unicolor roller base. After dozens of time doing this, I have yet to see any wear on the bases of my JOBO drums.

thanks for the tip. I am building version 2 using a wiper motor as now I got a bigger drum. If I ever finish doing it , I will post it here.

[Tin Can]

Maybe I missed it. Does it reverse or not?

Nice DIY!

[pound]

Maybe I missed it. Does it reverse or not?

Nice DIY!

Yes.. the Arduino code will make change the direction of rotation every 30 seconds or so. I may finetune this along the way.

Sent from my Redmi Note 3 using Tapatalk

[Graham Patterson]

You will need to be careful about leveling the drum (not just the base). You need to keep the depth of the chemistry constant. It's something you have to watch with Jobo processors, too.

[domaz]

You will need to be careful about leveling the drum (not just the base). You need to keep the depth of the chemistry constant. It's something you have to watch with Jobo processors, too.

It's also a good idea to always put in a little more chemistry than called for just for "insurance" against things not being completely level. I've always added an extra 30-50ml and never had an issue, even though my Jobo isn't levelled to an exacting degree.