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Photo Engineer
02-26-2012, 06:15 PM
I've used some like those!

Lots of fun.

PE

Prof_Pixel
02-26-2012, 06:48 PM
I've used some like those!

I'm sure you did!

Fred

AgX
11-06-2012, 06:02 PM
Seemed like the appropriate place to post this...

This Laboratory Drawdown Coater looks awesome -> http://www.chemsultants.com/testing-equipment-products/sample-preparation-devices/laboratory-drawdown-coater.aspx

The prime-inventor of Agfacolor once stated that he could carry his in the 40's home-built coater for Agfacolor type film under his arms for a walk...

AgX
11-06-2012, 06:05 PM
Back to the original topic of this thread:

What happened to the Filminator?

Photo Engineer
11-06-2012, 06:22 PM
The prime-inventor of Agfacolor once stated that he could carry his in the 40's home-built coater for Agfacolor type film under his arms for a walk...

I have seen that coater, and I know its advantages and limitations.

PE

semi-ambivalent
11-06-2012, 06:41 PM
And probably cheaper than to purchase. The quote from them came in at 6500.00 USD, but you must consider that this is new, with warranty, and expecting to be serviced, and prepared to offer support to an industrial customer instead of a hobby market.

All in all, it probably isn't too outrageous for an industrial customer that wants a coater that "just works out of the box" and doesn't want to fool with it. But it is a bit steep for a guy in a hobby market. I certainly have paid more than that for industrial equipment that "just works" although not quite something as simple as this looks.

But I'll bet something turns up on fleaBay once in a whole lots cheaper.

Not too bad at all. Remember, the "hobby market" is providing at least some of the demand for $7,000.00 Leicas. If the apocalypse comes a small group could go in on this for a simple B&W emulsion. In the meantime your film needs can be supplied by any of several manufacturers.

I've never made and coated my own emulsion but it actually looks pretty simple (a wire wrapped rod; how elegant!) How come nobody talks about the sprocket hole puncher? Now that's something the home-made folks could get their teeth into.

s-a

AgX
11-06-2012, 06:45 PM
That handmade coater was only made to show the feasability of manufacture to future clients, not to imitate the Agfa coater on which Agfacolor had been made for the preceeding 10 years.

AgX
11-06-2012, 06:51 PM
How come nobody talks about the sprocket hole puncher? Now that's something the home-made folks could get their teeth into.

A simple perforator is within the capability of of anybody with some drilling and milling machinery.

Off the shelf solutions have also been suggested by using cine-splicers.

michaelbsc
11-07-2012, 01:14 AM
Not too bad at all. Remember, the "hobby market" is providing at least some of the demand for $7,000.00 Leicas. If the apocalypse comes a small group could go in on this for a simple B&W emulsion. In the meantime your film needs can be supplied by any of several manufacturers.

I've never made and coated my own emulsion but it actually looks pretty simple (a wire wrapped rod; how elegant!) How come nobody talks about the sprocket hole puncher? Now that's something the home-made folks could get their teeth into.

s-a

For myself, if I were coating I would likely be targeting 120 size. Then the issue becomes a stable backing paper which doesn't interact with the film instead of how to punch holes.

For what is likely not going to be as good as Plus-X or FP4, I suspect a homemade emulsion would benefit greatly from the larger negative size.

Stable, chemically inert backing paper isn't so easy, however. About the cheapest I ever saw was the stuff on the Shanghai GP3 Chinese film. It seemed almost like children's construction paper. Then you have to print numbers which are chemically inert.

None of this is impossible, but it sure isn't trivial.

Steve Smith
11-07-2012, 02:04 AM
I think that if I was going to make my own emulsion, I would be more interested in coating glass plates than a flexible film.


Steve.

Mr Bill
11-07-2012, 06:01 AM
A simple perforator is within the capability of of anybody with some drilling and milling machinery.

Off the shelf solutions have also been suggested by using cine-splicers.

I don't think it's near as easy as it may seem, at least beyond test samples. When manufacturing film, you want to be especially careful that the punched chips (all of them) are completely removed. And that the perforations are clean, with no ragged edges or broken chips laying near the edge. Anything left behind has the potential of ending up in a good frame during the exposure. Or remaining trapped in the edge of the film gate for the rest of the roll.

In order to punch clean perforations, the punch and die set needs to have a certain clearance, which depends on how the film base shears. And if it is to be a commercial product, the perfs ought to conform to the ANSI/ISO standards for size and spacing, etc. I can probably dig up some of these dimensions (older ANSI specs), if anyone needs them.

A machinist who maintained some of this gear for a manufacturer once explained some of the difficulties to me; some extraordinary precision is called for. (I wonder if any of the perfing machines showed up in the book, Making Kodak Film.)

AgX
11-07-2012, 06:08 AM
We are not speaking of a commercial product here to my understanding. I know the specification of the perforations and I know the industrial perforators, but I also know how to get some perforations into the base. Between that there is a wide span.

Mr Bill
11-07-2012, 06:39 AM
But who would even shoot the film, aside from testing, if there was even a slight risk of loose film chips in the roll?

I can understand shooting on hand-coated emulsions, with intermittent defects. But a single small chip, caught in the film gate, could scratch the entire rest of the roll.

holmburgers
11-07-2012, 06:45 AM
Yesterday at GEH I actually got to lay eyes on an old Kodak perforater. Unfortunately it's in the collection so that means it'll never be used again, but, I agree with AgX that it should be a relatively simple task for anyone who is good at milling and machining.

In fact, although not for making perfs, in the labs down here I've come across these two little film splitters with stickers that say RIT on them. They are for splitting 4" film down to 35mm, and the other is for splitting 35mm down to 16mm. The bigger is driven by a motor and the smaller by hand crank. My point in mentioning these is that the construction of them is very simple, but they are also incredibly well made, with very high tolerances, and they work like a charm.

If somebody at a technical university can put these things together, a film perforater for medium quantity production would be easy enough me thinks.

Steve Smith
11-07-2012, 07:30 AM
It's not precision which stops loose pieces from the perforations from appearing on the film, it's clever design. Putting thought into the method and designing a mechanism which takes away all the loose pieces effectively shouldn't be too difficult.

If it has been done before, it can be done again.


Steve.

Mr Bill
11-07-2012, 07:51 AM
It's not precision which stops loose pieces from the perforations from appearing on the film, it's clever design.

Well, it's both. I had a special tour, for a specific purpose. They let me perforate a couple thousand feet of film in the process so that I would understand the issues. A guy who worked on them answered a lot of questions for me, so I'm working from that understanding. I'll just repeat that I think it's much more difficult than meets the eye. If one were to punch ROUND holes, and didn't mind the occasional perf hanging by a stretched bit of base, it would probably be a lot easier. I don't want to say too much more than I have.

semi-ambivalent
11-07-2012, 07:53 AM
For myself, if I were coating I would likely be targeting 120 size. Then the issue becomes a stable backing paper which doesn't interact with the film instead of how to punch holes.

For what is likely not going to be as good as Plus-X or FP4, I suspect a homemade emulsion would benefit greatly from the larger negative size.

Stable, chemically inert backing paper isn't so easy, however. About the cheapest I ever saw was the stuff on the Shanghai GP3 Chinese film. It seemed almost like children's construction paper. Then you have to print numbers which are chemically inert.

None of this is impossible, but it sure isn't trivial.

Michael,

Good points. I mentioned 35mm because that's my need :). It's also narrower and more rolls could come out of a single product run of what might be an expensive product. The paper backing would present issues if the film were stockpiled already rolled. If this were treated somewhat similar to 35mm one could spool it with re-used paper as it was needed. Your camera is already able to advance just the right amount of film between exposures, all the numbers do is help the aging brain keep track of how many times it has done its job. Perhaps buy a couple thousand feet of this paper from Kodak's supplier and re-use it until the zombies are at the door. If there was a little polyester in the paper it might not have to be so disposable.

No, this is not trivial. Think of it as keeping the glass plate guys from having the last laugh. (I could coat microscope slides and use them in my Nikon as a one-shot.) :p

s-a

Steve Smith
11-07-2012, 09:31 AM
I can immediately think of two perfectly good ways to perforate film. The first would be a matching set of male and female rotating dies which pull the blank film in and push it out with holes in it. The other way would be a flat male and female die which cuts a small lengh of the film which is then indexed along and uses the last two perforations cut to register the next set.

The rotating dies method is the way to go if you are doing a lot of film and want to run fast. The flat die method would be easier for a hand operated, low quantity production run. We have small hand operated machines at work similar to this for punching polyester sheet.

If you were happy with round perforations, a pair of drilling heads and an automatic advance mechanism would work but I would rather deal with perforation sized pieces than the swarf from drilling.


If one were to punch ROUND holes, and didn't mind the occasional perf hanging by a stretched bit of base, it would probably be a lot easier. I don't want to say too much more than I have.

Actually, with holes under about 3mm diameter, the shape doesn't matter much. 2mm punches in a steel rule die type of tool do not last very long. In a two part male and female die set, it doesn't matter much what the shape is.

What we need to do is scale it up. Make film just over four inches wide and perforate it with larger holes to make easily advanced rolls of film for large format cameras!


Steve.

dwross
11-07-2012, 09:53 AM
It's fantastic to see these older threads get up on their legs and run again. The Big Wheel keeps turning. The newest photographers get acquainted with the vocabulary and culture and materials of the older photographers, all with an eye on the potential for the latest technology to keep the older technologies alive -- at least as artisan niches. And, besides, it gives us something to talk about!

I'll throw in a couple of thoughts. 1) I don't think backing paper is an issue. Thin, acid-free, black paper is available from the Paper Art world.

2) When you're designing a sprocket hole puncher, keep in mind that it will probably work best to first coat and dry the film and then slice and punch it. Otherwise, you'll fill the sprocket holes with emulsion, which is nearly as hard as PET. (I'm assuming small scale machinery all along the process.) That means the hole punching will have to be done in the dark, and care taken to prevent scratches on the emulsion.

d

anikin
11-07-2012, 10:21 AM
I'll throw in a couple of thoughts. 1) I don't think backing paper is an issue. Thin, acid-free, black paper is available from the Paper Art world.


Denise,

Can you point out which exact paper you are talking about? For a while, I've been contemplating to try to make a few rolls of 122 film for my Kodak 3A camera. It should not be difficult to manufacture spools from 120 leftovers, and I think I have most of the ingredients for the emulsion, but the lack of backing paper has been stopping me.

Thank you,

Eugene.