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Jeff Dexheimer
14-Feb-2014, 10:24
In the intrest of doing market research, I have a design in mind and on paper for a sheet developing system. I am want to determine if it would be worth my effort to proceed to the next step, so I am asking for your input.

Here is the gist of how it would work:
1. It would be a tray system of sorts, allowing the user to agitate their film by rocking the system much like tray processing for developing paper.
2. You would be able to develop up to 10 sheets (of 4x5, less for 5x7 and 8x10) at a time and as few as one.
4. All 10 sheets would remain separate from each other. No sheet of film would touch another sheet of film.
3. It would be light tight as soon as it is loaded with film and properly sealed. It would remain light tight through the entire process, so it would be considered a daylight tank.
4. You could process all 10 sheets of film for different time intervals, so it would be fully zone system reedy.
5. Would use no more than a liter of developer per development.
6. Extreme ease of use. It would be easier to load than your standard film holder
7. *only a slight possibility* it would be temperature controlled. This would probably add significantly to the cost.

I would start this unit with a price-point of about $80.

My question then becomes, would enough people want one? If it were you and you saw a system like I described would you likely pay $80 for it?

ScottPhotoCo
14-Feb-2014, 10:33
It sounds interesting. What size (s) of film would it accept? How difficult is it to clean and store?

Tim
www.ScottPhoto.co

jp
14-Feb-2014, 10:35
I'd try that for $80. Temperature control isn't important, different time intervals isn't important, but it could be handy for developing more than one type of film at the same time if it were practical.

I've used tray, combiplan, and mod54 so far and use the combiplan mostly, and without problem, but I don't love it.

brucep
14-Feb-2014, 10:51
Yes definitely

Nicolasllasera
14-Feb-2014, 11:03
I would give it a try. Sounds good.

Jeff Dexheimer
14-Feb-2014, 11:42
Awesome, sounds like a positive start. Tim, it would have to come in different sizes. I would likely make a 4x5 version and 8x10 version. If there is enough interest in 7x5, I would make that available too.

Per Madsen
14-Feb-2014, 12:54
Yes, absolutly.

Andrew O'Neill
14-Feb-2014, 13:02
Quite possibly... I'd need to see more, like a schematic or something.

gleaf
14-Feb-2014, 13:08
Take a 4 x 5 film hanger, cut the top off so you have just the lower frame and film gate. 4 fit in an 11 x 14 tray. 4 at a time tray development. No abrasion to the film. It is seldom cost effective to reinvent a working wheel and there are several out there. Never the less. good luck. One must try or one does not learn.

Leigh
14-Feb-2014, 13:15
5. Would use no more than a liter of developer per development.
The required volume of developer varies with the dilution and the number of films.

For example, Rodinal at 1:100 requires 1000ml total volume for 10 4x5 films.

At 1:200, it requires 2000ml for 10 4x5 films (this dilution is beyond manufacturer's recommendations).
In this case, you could only do a maximum of 5 4x5 films.

-----

One critical aspect regarding acceptance of the product is absolute even development.
A common problem with sheet film tank development is uneven density due to turbulence.

- Leigh

Bob Mann
14-Feb-2014, 13:15
I would be interested in 5x7 and possibly 8x10 -

Pawlowski6132
14-Feb-2014, 13:30
What's it made out of?

Bill_1856
14-Feb-2014, 13:44
The slosher is the best way to develop multiple films without getting your hands wet, or the possibility of scratching a negative.

http://stores.photoformulary.com/formulary-sheet-film-developing-trays/

Jeff Dexheimer
14-Feb-2014, 14:02
As far as material is concerned, I can't yet say specifics, as I am not that far into it. Right now it is a concept on paper, but from the design, I can say I would use an opaque plastic material, perhaps something along the lines of a similar plastic that current dumbs are made of.

Leigh, that's why I have it set up for upto 10 sheets. I am certainly not aware of all possible developers, but I am familiar with rodinal. Knowing that many people still use it, myself included, I set the upper limit to 10. It would be able to develop anything up to that number.

The sloshes trays are nice, but they are not a daylight tank. My design would be daylight safe and assuming it is used correctly, fool proof for getting unscratched, evenly developed negs.

angusparker
14-Feb-2014, 14:08
I would be intersted

kmack
14-Feb-2014, 16:55
At an $80 price point, sure.

rcmartins
14-Feb-2014, 17:37
Since you say it will be akin to a tray I am guessing it won't be particularly suited for standing or semi-standing development. The problem I have with the patterson orbital, which I am guessing is similar to your design, is the bromide deposition. Vertical tanks, on the other hand seem to waste too much chemicals.
raul

Jeff Dexheimer
14-Feb-2014, 20:52
It should be suitable for stand development, but that I can honestly say that is a technique I am not perfectly familiar with.

I should note, that I have yet to see anything, current or past, that approximates this design. The best I can describe it would be souped-up tray processing. My next step is cost analysis. Again this idea is still a long way off, but it is something I am pretty excited about. I just wish I thought of it 30 year is ago when sheet film was all the rage!

AtlantaTerry
15-Feb-2014, 00:29
I would take a 4x5 version at $80.

Tim Meisburger
15-Feb-2014, 01:11
ya, me too... and 5x7...

rcmartins
15-Feb-2014, 01:37
If it does indeed avoid the bromide deposition I would too. A tray could do it if it allowed for the emulsion side to be placed facing downwards without scratching. I believe a tray with lateral rails could do the trick.
Anyway, I would buy it, yes. After having tried the yankee tank, the nikor tank, the modified orbit and simple trays, I have chosen the yankee tank as the best for my semi-stand procedure, but have always been disturbed by the 1,65 l it requires.
raul

Regular Rod
15-Feb-2014, 03:53
In the intrest of doing market research, I have a design in mind and on paper for a sheet developing system. I am want to determine if it would be worth my effort to proceed to the next step, so I am asking for your input.

Here is the gist of how it would work:
1. It would be a tray system of sorts, allowing the user to agitate their film by rocking the system much like tray processing for developing paper.
2. You would be able to develop up to 10 sheets (of 4x5, less for 5x7 and 8x10) at a time and as few as one.
4. All 10 sheets would remain separate from each other. No sheet of film would touch another sheet of film.
3. It would be light tight as soon as it is loaded with film and properly sealed. It would remain light tight through the entire process, so it would be considered a daylight tank.
4. You could process all 10 sheets of film for different time intervals, so it would be fully zone system reedy.
5. Would use no more than a liter of developer per development.
6. Extreme ease of use. It would be easier to load than your standard film holder
7. *only a slight possibility* it would be temperature controlled. This would probably add significantly to the cost.

I would start this unit with a price-point of about $80.

My question then becomes, would enough people want one? If it were you and you saw a system like I described would you likely pay $80 for it?

Yes if it can be used for semi-stand and stand development. How will it do different times for ten sheets?

Will it be like a better version of this http://freepdfhosting.com/f640343f29.pdf ?

RR

Regular Rod
15-Feb-2014, 03:57
Since you say it will be akin to a tray I am guessing it won't be particularly suited for standing or semi-standing development. The problem I have with the patterson orbital, which I am guessing is similar to your design, is the bromide deposition. Vertical tanks, on the other hand seem to waste too much chemicals.
raul

What is this problem?

RR

Regular Rod
15-Feb-2014, 03:59
It should be suitable for stand development, but that I can honestly say that is a technique I am not perfectly familiar with.

I should note, that I have yet to see anything, current or past, that approximates this design. The best I can describe it would be souped-up tray processing. My next step is cost analysis. Again this idea is still a long way off, but it is something I am pretty excited about. I just wish I thought of it 30 year is ago when sheet film was all the rage!

Tray is perfect for stand and semi-stand development so your system should be okay.

RR

Scotty230358
15-Feb-2014, 04:47
I would certainly be interested. My Jobo Expert tank is the easiest tank to load I have, my Jobo 25 is harder to load and uses nearly 1500cc of chemicals but it can be used for inversion agitation which is the development method I am most used to. Just one question - do you think your device can be used for intermittent agitation or would constant agitation be the only practicable method.

brucep
15-Feb-2014, 05:15
Put me down for a 5x7 and a 10x8

Len Middleton
15-Feb-2014, 07:09
Jeff,

It sounds intriguing, and sounds like you understand a number of the potential issues.

Would be interested in your progress, and at $80 it would be easy to finance through the selling of a used Jobo Expert tank if it proves to be better.

You still have the issue of converting market research into some understanding of what the market actually might be. That will of course impact projected volume and affect your manufacturing processes (small volume prototyping, versus mass production).

Good luck with it and keep us posted. And for $80 for a 4x5 or an 8x10, it is worth the investment to me.

Hope that helps,

Len

koh303
15-Feb-2014, 07:13
My design would be daylight safe and assuming it is used correctly, fool proof for getting unscratched, evenly developed negs.
Can you offer some more insight on how this will work? how can you can have different times for different sheets? if it is fool proof, why do you need to assume it will be used correctly?
How will the sheets be held in a way that prevents flow marks or patterns?
If you use only 1 sheet do you still need a full 1 liter of liquid?
This sounds like a great concept, with the list of things it could do, and a great price point i wish you good luck in bringing this to market, though its hard to see how this will be achieved, regardless of price.

Bob Salomon
15-Feb-2014, 08:28
Back in the 70s a fellow named Sam Needleman along with a camera stow owner named Bobby Olden came up with a daylight print processing system called the Agnecolor processor that was marketed by EPOI. It was an inclined plane which washed chemistry over the print. Your description kind of reminds me of the basic model modified for film rather then prints.

They marketed the technique as a "Laminar Flow" process.

rcmartins
15-Feb-2014, 09:09
While developing the exposed silver bromide crystals in the film emulsion are converted to free silver and a bromide ion. The free silver remains in the emulsion (later removed by the fixer) and the bromide is released to the developer. As far as I know, but I am not a chemist, the bromide ion will affect the developer since it is a restrainer and I believe it is the reason why potassium bromide is added to a developer, to avoid chemical fogging. If the released bromide stays on top of the emulsion it will affect development and improper agitation, either too much or insuficient, will give rise to trails of uneven development which I am guessing are called bromide drag patterns.
I am not absolutely sure about this. As I said, I am not a chemist. But my experience is that indeed tray development with stand development, at least the way that I do it, gives very distinct patterns of uneven development that I do not get when the emulsion is vertical.
I would very much appreciate if someone really knowledgeable on this topic could provide a more solid explanation to the chemical roots of uneven development and its relation to agitation and orientation in development tanks.
raul


What is this problem?

RR

Andrew O'Neill
15-Feb-2014, 10:35
Tray is perfect for stand and semi-stand development so your system should be okay.

I have to partly disagree, Rod. In my experience (using Pyrocat-hd and Obsidian Aqua), trays are okay for semi-stand but not for stand development. A vertical configuration is the way to go for stand.

Regular Rod
15-Feb-2014, 10:37
But if you lay the sheets emulsion side down...?

RR

Andrew O'Neill
15-Feb-2014, 10:40
Interesting. I've never tried that, always being an emulsion side up guy. Now you've given me something to do today...! Thanks Rod.

rcmartins
15-Feb-2014, 11:10
That has the danger of promoting scratches, as I stated previously, and that is why I suggested the use of lateral rails to help prevent the emulsion to touch the bottom of the tray. The rails could be slightly slanted as Bob mentioned. Nevertheless, I brought this subject because I would definetely buy a tank that is appropriate for stand and semi-stand development while allowing the development of a single sheet or a small number of sheets without wasting too much chemicals, or water for that matter. The OP seems to be confident his design will allow this. I sure hope so.
raul


But if you lay the sheets emulsion side down...?

RR

Regular Rod
15-Feb-2014, 12:15
The bottom of my Patterson Orbital is dotted with soft, smooth beads of epoxy resin. Combined with stand development the agitation is so minimal I seem to get away with it. Lots of old timers used to develop their films in trays emulsion side down. I prefer the emulsion side up for semi-stand but not if using stand.

RR

JoeV
15-Feb-2014, 15:02
The first thing I'd want to know about this new system before promising to pony up some cash is how quickly chemicals can be poured in & out. If it's as slow as a Yankee tank, then it's pretty useless. I'm assuming from the OP's description that, once loaded into the system, complete processing from developer through fixer can be achieved in room light? Quick dumping and repouring of chemistry is crucial to consistent processing. I'd need to know more information, first.

~Joe

PS: After four pages of responses, no one thought of asking about repour capacity? Isn't that the main gripe people have with the Yankee tank? (And also unevenness of developement.)

Leigh
15-Feb-2014, 15:56
no one thought of asking about repour capacity?
I assume you're talking about the time it takes to fill the tank with solution.
That's because it's irrelevant, as long as your technique is uniform.

If it takes 10 seconds to fill the tank...
The upper area of the film will start developing 10 seconds later than the bottom.
Of course, the same is true for the stop bath, so developing stops 10 seconds later.

The entire film develops for exactly the same amount of time.

- Leigh

koh303
15-Feb-2014, 16:07
Isn't that the main gripe people have with the Yankee tank? (And also unevenness of developement.)
That, and being impossibly hard to load, they leak, break easily, require a huge amount of chemistry... am i forgetting something else?

Gary Samson
15-Feb-2014, 19:00
I would be very interested in this tank for myself and for the college I teach for. How about a Kickstarter project to make this a reality?

Geraldine Powell
15-Feb-2014, 21:21
It is interesting, but I don't like that it takes a liter. I love my orbital processor that only takes 120ml for four 4 x 5 sheets. I also like my BTZ tubes, but of course they are not daylight. I would definitely buy it to try it out.
Geraldine

Jeff Dexheimer
15-Feb-2014, 22:46
Pretty positive responses so far. To answer a few of the questions...

1. I don't do stand development myself, but from your description, it would allow stand and semi stand development without any problems.

2. I don't mean to agitate anyone (ha, pun intended) but I don't want to be too descriptive on its workings until I have filed for a patent (if I get that far with it).
3. The amount of chemistry needed would be 1 liter only if developing, say 10 sheets in rodinal. Fewer sheets would require less chemistry.
4. I almost forgot. Flow rate is an important consideration. The design allows for an extreamly fast fill and empty rate. Of course, since it is only in the concept stage, I cannot do more than give hypothetical flow rates, but think a Patterson tank or slightly faster. I have never had a problem with uneven dev in one of those.

Based in what I am hearing, I think it's time to build a prototype. If all goes well, I'll start doing some I depth market research and see what happens.

Andrew O'Neill
16-Feb-2014, 11:09
I also like my BTZ tubes, but of course they are not daylight. I would definitely buy it to try it out.

BTZS tubes are daylight. Of course you load them in the dark like all daylight systems, but develop in the light. You can even keep the light on in the stop and fix. I do all the time.

the smiling gecko
16-Feb-2014, 11:40
absolutely, positively in for an alternate system to develop 4x5 and 8x10.

WayneStevenson
16-Feb-2014, 11:56
" I don't mean to agitate anyone (ha, pun intended) but I don't want to be too descriptive on its workings until I have filed for a patent (if I get that far with it)."

Not to be too cynical, but you're wanting to patent a process for a niche hobby market that arguably is getting smaller with every passing month? In terms of photographic processing techniques, you will be hard pressed to come up with something that hasn't already been patented. Over 100 years of the world's best minds worked for the best companies to put out what is no longer being manufactured. It is going to cost you far more to have someone search through patents, than you probably will make back in profit.... Just a thought.

Your market is small and realistically will probably only supplement your income from your day job or retirement.... I personally wouldn't worry. I would be more open with your idea to ensure it is sound. And a lot of us have experimented a lot to make our lives easier. So someone here may be able to share their own experiences down that line.

Have you manufactured a prototype yet?

djdister
16-Feb-2014, 13:13
I would tend to agree with Wayne. There have been a lot of designs created over the years, and it is hard to believe that you have come up with something truly different. We have round tanks, square tanks, trays, dip tanks, daylight tanks, tubes, and drums. The only thing that could possibly be different would be the equivalent of a covered tray, which is really just a reclining version of a skinny dip tank. I've got a version of a 5x7 daylight dip and dunk processing tank - the film and hangers hang in a daylight tank with lightproof but not liquid proof baffles at the bottom. Once the film and hangers are loaded, you can just dip the whole film tank in 3 successive baths.

Anyway, I seriously doubt the claim that this single tank could facilitate differing process times for the sheets within it. You've described a holy grail of requirements, but I wouldn't put any money down until I saw a concept drawing at the very least. Maybe others are a bit more free with their money though...


" I don't mean to agitate anyone (ha, pun intended) but I don't want to be too descriptive on its workings until I have filed for a patent (if I get that far with it)."

Not to be too cynical, but you're wanting to patent a process for a niche hobby market that arguably is getting smaller with every passing month? In terms of photographic processing techniques, you will be hard pressed to come up with something that hasn't already been patented. Over 100 years of the world's best minds worked for the best companies to put out what is no longer being manufactured. It is going to cost you far more to have someone search through patents, than you probably will make back in profit.... Just a thought.

Your market is small and realistically will probably only supplement your income from your day job or retirement.... I personally wouldn't worry. I would be more open with your idea to ensure it is sound. And a lot of us have experimented a lot to make our lives easier. So someone here may be able to share their own experiences down that line.

Have you manufactured a prototype yet?

DrTang
17-Feb-2014, 11:12
put me down for a 5x7 one if it can do stand developing


I myself was about to think about (yes..about to think about) making some kind of box to hold 3 5x7 hard rubber tanks so I could stan develop 10 sheets..say daylight.. but if you come up with something.. that would make my life easier considering my carpentry skills

Myxine
19-Feb-2014, 12:12
I'd definitely be interested in a 4x5 and even maybe a 8x10. Since developping 8x10 sheets is the limiting factor for me right now to jump a higher format, I'd be very interested.

And if you're doing a market study, I'd be interested even if there was much less sheets stored in a tank (say - 2 I prefer to process slowly but carefully)

gevalia
24-Feb-2014, 15:09
I'd be interested in a 4x5 tank.

A few comments:
1. Just have people sign an NDA. I was able to get a patent 10 years ago and have applied many times since and have successfully used NDA's. An NDA route is a good one.
2. The deal breaker for me is how quickly the tank drains. One of the daylight tanks I played with took 11 seconds to empty. That is a lifetime.
3. I now only use an HP-Combi tank for 4x5. For safety, I only load 4 sheets at a time max and I do stand and semi-stand as well as divided developers (pyro). Even if it did 10 sheets, I would never do 10 at a time. I would not risk 10 negatives at once and this has nothing to do with tank design. But I like that it will not take more than 1 liter of developer.

Also, give some thought to a parts catalog. One think I liked about the HP-Combi was that I could buy individual parts and over the past few years I have stocked up on replacement parts since it is now out of MFG.

Good luck!
Ron

koh303
24-Feb-2014, 16:34
2. The deal breaker for me is how quickly the tank drains. One of the daylight tanks I played with took 11 seconds to empty. That is a lifetime.
I do stand and semi-stand as well as divided developers (pyro).

If you do stand development why is 11 seconds a lifetime?

propellerhead
25-Feb-2014, 08:04
I'll Bite,
Sounds like a great idea, keep us posted Jeff. $80.00 is fair enough.

Bob Salomon
25-Feb-2014, 09:41
I'd be interested in a 4x5 tank.

A few comments:
1. Just have people sign an NDA. I was able to get a patent 10 years ago and have applied many times since and have successfully used NDA's. An NDA route is a good one.
2. The deal breaker for me is how quickly the tank drains. One of the daylight tanks I played with took 11 seconds to empty. That is a lifetime.
3. I now only use an HP-Combi tank for 4x5. For safety, I only load 4 sheets at a time max and I do stand and semi-stand as well as divided developers (pyro). Even if it did 10 sheets, I would never do 10 at a time. I would not risk 10 negatives at once and this has nothing to do with tank design. But I like that it will not take more than 1 liter of developer.

Also, give some thought to a parts catalog. One think I liked about the HP-Combi was that I could buy individual parts and over the past few years I have stocked up on replacement parts since it is now out of MFG.

Good luck!
Ron

But have you ever had to defend your patents in court?

Jim Noel
25-Feb-2014, 09:57
I have never found a daylight tank for sheet film which suited me, and this one sounds no better. NO thanks.

koh303
25-Feb-2014, 13:40
But have you ever had to defend your patents in court?

I can only guess that if someone was to "infringe" on a patent whose entire market base was 1000 users globally over an 80$ retail price their cost would be more then they would ever make back in sales, considering at least a few poeple already bought the first design...

Bob Salomon
25-Feb-2014, 14:00
I can only guess that if someone was to "infringe" on a patent whose entire market base was 1000 users globally over an 80$ retail price their cost would be more then they would ever make back in sales, considering at least a few poeple already bought the first design...

Agreed, but we have been fighting a patent suit for over 6 years and it is really a royal PITA! It is not a photographic patent however!

rcmartins
25-Feb-2014, 14:40
Not to derail this thread any further but any IPP (Intelectual Property Protection) requires a lot of money to backup. A clear advantage is on the side of the party with the higher financial capability. Patents, and NDAs for that matter, are close to useless for those with little funds.
raul

koh303
25-Feb-2014, 15:05
Not to derail this thread any further but any IPP (Intelectual Property Protection) requires a lot of money to backup. A clear advantage is on the side of the party with the higher financial capability. Patents, and NDAs for that matter, are close to useless for those with little funds.
raul

That has been my experience as well, with the amount of funds required to even begin the filing by far outweighing the over all cost for R&D, and the actual possible projected future profits making such an investment not relevant, however, some might do/find/feel otherwise.

arca andy
27-Feb-2014, 17:30
Anyway, moving on.
$80, what ever that is in ús, sounds good...I've just bought the MOD54 Patterson thingy and that's ok, if a little limited in the fact you have to own a Patterson tank, it only processes 6 sheets a go and it only accepts 5x4 ... So if your system can tick more boxes than that .....then whats not too like?

Jac@stafford.net
27-Feb-2014, 17:38
I have a rotary tube-tank that can process up to 24 sheets of 4x5 at once, and by removing segments as few as 8 sheets.

Cost me nothing. There is not much new under the sun in this area.
.

NancyP
20-Mar-2014, 15:13
I am always open to trying something. But I am a rank beginner with no lifetime habits of tray/tank/Jobo (pick one) processing.

Len Middleton
28-Mar-2014, 18:43
Not to derail this thread any further but any IPP (Intelectual Property Protection) requires a lot of money to backup. A clear advantage is on the side of the party with the higher financial capability. Patents, and NDAs for that matter, are close to useless for those with little funds.
raul

Being right, and having rights is of little value if you cannot defend them; money seems to be the primary determinant as to who wins in a court fight...

mpirie
29-Mar-2014, 00:54
This is definitely a thread i'll watch with interest !

I'd be willing to give it a go for $80 !!

Jac@stafford.net
30-Mar-2014, 14:45
Funny, but after decades of agitation woes I have settled on modest Besler drums for 4x5 and 8x10.

The next step, should I be crazy or brave enough is to try my Big commercial Drum that can do 24 sheets of 4x5 at once. (Ain't ever gonna happen)

koh303
30-Mar-2014, 15:51
Funny, but after decades of agitation woes I have settled on modest Besler drums for 4x5 and 8x10.

The next step, should I be crazy or brave enough is to try my Big commercial Drum that can do 24 sheets of 4x5 at once. (Ain't ever gonna happen)
What drum does 24X 4X5 ?

Filmnut
1-Apr-2014, 15:18
This sounds like something I'd go for to. I'm using the Combiplan tanks, which are the best tanks I've used. Hope you can make it reality.
Keith

StoneNYC
1-Apr-2014, 19:28
This sounds great!

Without naming names, I would suggest not taking the harsh criticism and doubts to heart. They are mostly just scared that you're smarter than them.

That and you'll be competition since one of the posters currently has a kickstarter for their own 8x10 system, ironically one of the ones who said the cost is too great and you shouldn't do it... I would take that as a complement, you've got him scared.... ;)

Jac@stafford.net
2-Apr-2014, 12:46
What drum does 24X 4X5 ?

When weather improves I will take it outside to make a picture of it.

Randy Moe
2-Apr-2014, 14:10
Yup, many agendas here. Perfectly normal.


This sounds great!

Without naming names, I would suggest not taking the harsh criticism and doubts to heart. They are mostly just scared that you're smarter than them.

That and you'll be competition since one of the posters currently has a kickstarter for their own 8x10 system, ironically one of the ones who said the cost is too great and you shouldn't do it... I would take that as a complement, you've got him scared.... ;)

Jeff Dexheimer
2-Apr-2014, 20:05
This sounds great!

Without naming names, I would suggest not taking the harsh criticism and doubts to heart. They are mostly just scared that you're smarter than them.

That and you'll be competition since one of the posters currently has a kickstarter for their own 8x10 system, ironically one of the ones who said the cost is too great and you shouldn't do it... I would take that as a complement, you've got him scared.... ;)

Thanks Stone, I find naysayers amusing. They simply can't fathom someone coming up with an idea they haven't thought of. I don't worry about that. Honestly I am still designing. I have the basics of the design figured out, but there a few details I still need to work through in the prototype, and considering I have more than a full time job, I am taking my time. Hopefully I'll have a working model in a few months.

Jim Andrada
3-Apr-2014, 10:32
Plastic by itself is cheap. Molds for making plastic parts are expensive - very expensive. We have a potential OEM customer for a 1 3/4" high by 19" wide rack mount product. They want a unique front bezel. We're looking at several $100k in up front costs for the tooling to make it. Admittedly it's a complex part because it has to have a molded-in grille for air circulation as well as fit precisely over some LED's and buttons etc. and meet flammability standards and not use environmentally deleterious chemicals, not warp even a little bit, etc etc etc.

For short run parts soft tooling is cheaper than hard tooling so probably good enough for the quantities you'd be looking at.

But I still think you'll be unpleasantly surprised at the cost of the molds.

gevalia
23-Apr-2014, 09:00
Jeff,

I'd certainly be interested in one if it was better than the daylight tank I use now. My current tank takes 30 seconds (if the gods are smiling on me) to unload developer and more on the 45 second times. I have learned to work with its quirks but is by no means great. 3 requirements I would have are a) easy to load 4x5 sheets, b) fast unloading of liquids and my reason for this is that I would like to be able to do divided developing where I need to completely unload liquid in a few seconds not a half a minute, and c) does not use more developer/fixer than my current setup with is around 1100ml - 4 or 6 sheets.

And I agree with the above, ignore the critisizms.

Ron

spkennedy3000
1-Jul-2014, 06:33
I want it please!

Bob Salomon
1-Jul-2014, 08:55
Jeff,

I'd certainly be interested in one if it was better than the daylight tank I use now. My current tank takes 30 seconds (if the gods are smiling on me) to unload developer and more on the 45 second times. I have learned to work with its quirks but is by no means great. 3 requirements I would have are a) easy to load 4x5 sheets, b) fast unloading of liquids and my reason for this is that I would like to be able to do divided developing where I need to completely unload liquid in a few seconds not a half a minute, and c) does not use more developer/fixer than my current setup with is around 1100ml - 4 or 6 sheets.

And I agree with the above, ignore the critisizms.

Ron
Are you opening the air path when filling or draining your tank but slightly twisting the Light Tight Hose Connector? That will give you the fastest fill and empty times on the Combi-Plan and fill and empty times should be the same if you have opened the air path.

Byclops
3-Jul-2014, 11:41
Does the design require exact film sizes for safe and effective processing? Specifically, would your 4x5 tank accommodate 3-╝ x 4-╝ sheet film safely?