Build a B&W film developing timer & twiddler - Cheap, Easy & it Works

[Niglyn]

Here is the lid with twiddler. 3d print files will be on github shortly.

I used a stopwatch or similar for timing & it may be a little overkill to have a colour tft timer, but it is nice to (easily) program in the dev/stop/fix & agitation times at the start & then not worry about remembering the times or continually stare at the stopwatch, as the Dev Timer gives an audible warning before each shake/twiddle is required.

The use of a 4 inch colour screen adds £8 to the cost, over using an LCD. It is possible to save a few £ by using a smaller tft screen. By using the bigger screen, all values can be displayed, without having sub-screens, so makes the Dev Timer far more straight-forward to use.

The Auto-Twiddler is completely optional & I doubt many people will use it, but it was only 1/2 hour of code writing & it is there if peeps want to try it.

The shake/twiddle debate will of course go on forever. It is personal choice. I can only say that the films that I twiddled, came out fine. I did not do any scientific experimentation, I just twiddled instead of shaking.
The Chinese developing tank is quite clever in that it also raises & lowers the reels during twiddling. Also the Chinese tank is for twiddling only, according to their instructions. I assume this is due to their lid fitting even worse than the Patterson ones )

My Jobo tank (sold years ago when we all moved digital) was the best for shaking. It's silicone-like lid gave a perfect seal & also allowed for air expansion.

(I do know how to agitate a tank correctly, I was taught over 30 years ago & have developed loads of film)

 

[GBS]

Here is a photo of the (new) 3d printed Patterson Super 4 Tank Lid.
It incorporates mounting for the stepper motor & teeth on the underside, to engage with the serrations on the tank rim.

A new twiddling stick will be available soon (printing now) which will connect directly to the stepper motor drive shaft.
stl print files on Github & Instructables.


Without a 3d printer, it is quite simple to make something similar from a piece of ply or plastic.

View attachment 369231

Nice work!

 

[GBS]

The Chinese developing tank is quite clever in that it also raises & lowers the reels during twiddling.

Could you link to an example of that tank? Thank you!

 

[Niglyn]

Hi,
Link below. Considering Aliexpress is usually very cheap, this tank and the Patterson clone that has started appearing are more expensive than a genuine Paterson tank.

With twiddling, one must ensure the end of the film does not curl round and touch the film on the next spiral in, else when twiddling, it will stop fresh chemical entering into the spiral. I cut the end of the film very slightly concave.

Next is to ensure, looking from above, the spiral is wound clockwise from centre to outside, again so when twiddling clockwise, fresh chemical gets pushed into the outer of the spiral and pushed through the film.

https://vi.aliexpress.com/item/10000001107139.html?spm=a2g0o.detail.pcDetailBottomMoreThisSeller.1.42c6HPXCHPXCfY&gps-id=pcDetailBottomMoreThisSeller&scm=1007.13339.291025.0&scm_id=1007.13339.291025.0&scm-url=1007.13339.291025.0&pvid=9b466f61-1d20-41e1-9519-a5f894cff02b&_t=gps-id:pcDetailBottomMoreThisSeller,scm-url:1007.13339.291025.0,pvid:9b466f61-1d20-41e1-9519-a5f894cff02b,tpp_buckets:668%232846%238115%232000&pdp_npi=4%40dis%21GBP%2132.82%2129.54%21%21%2140.00%2136.00%21%40211b80d117145051472275900e14e0%2112000030772084512%21rec%21UK%212089347981%21&utparam-url=scene%3ApcDetailBottomMoreThisSeller%7Cquery_from%3A

 

[GBS]

Hi,
Link below. Considering Aliexpress is usually very cheap, this tank and the Patterson clone that has started appearing are more expensive than a genuine Paterson tank.

With twiddling, one must ensure the end of the film does not curl round and touch the film on the next spiral in, else when twiddling, it will stop fresh chemical entering into the spiral. I cut the end of the film very slightly concave.

Next is to ensure, looking from above, the spiral is wound clockwise from centre to outside, again so when twiddling clockwise, fresh chemical gets pushed into the outer of the spiral and pushed through the film.

https://vi.aliexpress.com/item/1000...cene:pcDetailBottomMoreThisSeller|query_from:

Great, thank you. I can't tell from the listing, but is this the one that lifts and lowers with the spinning? Thank you.

 

[Niglyn]

Yes this is the one that raises and lowers the spiral as it is twiddled.

I do not know if the Patterson tank has enough space for a little 3d printed wavy washed to be added, to enable it to oscillate as well.

Note the 3d printed parts as shown, are only designed to fit the Patterson Super System 4 tank.

 

[GBS]

Yes this is the one that raises and lowers the spiral as it is twiddled.

I do not know if the Patterson tank has enough space for a little 3d printed wavy washed to be added, to enable it to oscillate as well.

Note the 3d printed parts as shown, are only designed to fit the Patterson Super System 4 tank.

Cheers, thanks a lot

 

[Jarda]

Great work, please send the User Key if you still need it. Thank you

 

[Radost]

please make a 70mm to 120 cutter roller machine.

 

[Niglyn]

Great work, please send the User Key if you still need it. Thank you

Hi, if you have built it and require the Pass Key, please send me a DM showing the Authorisation code on the screen.