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03-25-2020, 03:14 PM   #31
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QuoteOriginally posted by photogem Quote
And you know this due to which personal experience/tests?


1. For making such a claim, you would have to have a white Japanese solenoid but you don't, which you made very clear earlier on!
2. The Japan Solenoid does not work with less power. It's magnet has less strength i.e. holding force. The different data of release time and holding
force are known! But this is only one aspect!


But the most important fact and were you are totally wrong:


3. The white solenoid never has failed, it even never started to fail!

It is basically a similar difference compared to a well built car-engine compared to an engine built to inferior standards.
If pistons are lose, you can file and sand around but the result would make any car-engineer laugh.
You can use better lube (oil), clean, polish, add additives... all this is a very nice pastime but here we are dealing with a small device which
is available.
Dear Photogem:
I make this statement based on your valuable data provided to the forum:
As you say, the white Japanese solenoid has less retention strength.
This is because its magnet has less magnetic force, as a result it will need less electrical power to be released. (Electric Power=VxI) That's all.

My previous Post is founded on the fact that the diaphragm control Block works well for a good period of time and should work again as a factory exit.

Applying its wise history, it is just about finding the key where there is no light and understanding what the function of each of the diaphragm control block components is. This is called reverse engineering.

It is my intention to collaborate with the forum and try to find an economical and simple solution to many users.

Understand that many people are far from consumer centers and it is very difficult to get components.

Best Regards.


Last edited by MarkJerling; 05-13-2020 at 03:13 AM. Reason: Fable quote removed.
04-01-2020, 02:21 AM   #32
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If you have a lock and a key and you find out, that the key doesn't quite fit, you have those possibilities:

1. You know there is a prober key which works 100%, so you go and get it
2. You try to file the key (or sand or grind or polish or oil it): It can work but still, but will never be as good as #1
3. You can try to take out the lock, dismantle it and manufacture a matching key: Reverse engineering: You can also try to built a complete new lock and key, even a new diaphragm controll block, even a new camera
4. You smash the key or the lock or both

This example of a key and lock is quite close actually to what we have with the solenoid.
Many of use once encountered probably problems with a key not quite fitting.
We might know very well that actually often the bad key finally brakes off or jams worse or the lock is damaged.

You see, this story of the man searching for his lost key is a very famous one, it is a wise story by Mullah Nasruddin,
the Till Eulenspiegel of the East.

As such, one has to go a step further: He is wise, so searching in the dark has a real meaning.

But this real search is for the engineers working for Ricoh because they have to solve this, not we.
I think we have helped them a tremendous lot, it was us here in the forum who found out the problem, not them!


I could go even further:

If you have a bad part in your body, lets say a tumor:
Usually you have to get it out, you don't file and sand and lube it!

Same for a bad joint, bone scratching bone: Too bad because you are in need of a sensible good new joint.

Or you've got a rotten tooth. No toothfairy will help!
04-02-2020, 01:05 PM   #33
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I have a feeling that removing the battery from the camera when not in use can prevent the solenoid from getting magnetized and therefore solve the dark frame problem.. It is probably due to a current leak from the battery that over long term storage does the damage. It is difficult to test this theory but perhaps smarter minds on this forum can advise.
04-02-2020, 09:11 PM   #34
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QuoteOriginally posted by ShawnH Quote
I have a feeling that removing the battery from the camera when not in use can prevent the solenoid from getting magnetized and therefore solve the dark frame problem.. It is probably due to a current leak from the battery that over long term storage does the damage. It is difficult to test this theory but perhaps smarter minds on this forum can advise.
You mean because the battery drains even when not in use?
This is not due to a leak but due to the construction of rechargeable batteries themselves.

There is no leak into the electronics of the slightest, this has been measured. The only electronic part with is not switched off when the camera itself is switched off is the backup battery*


The problem does occur with or without the battery inside and it is a problem of the plunger being constant in touch with the permenent magnet.
The underlaying problems are:
- that the holding force of the chinese made solenoid is too strong the release time longer (something which doesn't get changed by the methods
Sergio Gonzales applies)
- the bearing-quality of the PET versus PTFE body the plunger moves in (this is approached by the methods of S. G.)

If there would be a constant current-leak from the battery it would also affect the white Japan solenoid

BUT...:
Keeping the battery out has another very negative side-effect:
*The small backup battery is constant fed so that it doesn't discharge. If one leaves the Pentax without battery too long this backup battery drains
and because it is a Li-Ion type, we know what happens when they discharge too much, they are damaged beyond repair. Thus one loses time and date settings everytime one takes the main battery off.

04-03-2020, 08:03 AM - 1 Like   #35
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Last observation

Dear Photogem.
Thank you for your opinion.

Now to end the problem of dark photos I must communicate the following to the Pentaxforum community:
To my post #29 I must add the following observation:

Repeat: the mechanism of the diaphragm control block is 90% analog and electromechanical and only 10% digital (counter of the windows of the exhaust wheel). It is for this reason that the new Pentax cameras have changed the diaphragm control block to a team commanded by a stepper motor. Many components that can be failed are saved.

The electromechanical mechanism of our K30/Ks2 is commanded by an electric motor, which puts in motion in 1/5.5 sec, a complex and heavy gear train and a pair of cams that move the diaphragm lens and mirror; which consume a much higher electrical power than the solenoid consumes.
Engine and solenoid operating times are synchronized by the switch mounted on one of the diaphragm control gears.
When the lubrication of the switch gets old and gets dirty, its contacts begin to introduce interference and electrical noises, in addition the lubrication of the cams and gears suffer the same aging producing the increase in consumption of the electric motor.
These two problems cause the diaphragm control to start to fail and take dark photos, as we explained.

The diaphragm control of my KS2 is in the 9500 shots and this new one.
The green solenoid is intact, clean and as the factory throws it. I took out the graphite, the supplements and proceeded to lubricate the Doaphram control block as follows and in this order:

1. The switch area, clean it with a powerful degreasing spray, and then place an efficient contact lubricant, for high precision equipment. Of which I add the link below.

2. Cams and gear train, with an aerosol developed for printer maintenance, from which I add the link below.

The lubricant has a teflonated base that dries and produces effective lubrication of plastic components.
Regarding the most demanding test that can be performed on a diaphragm control block, it is:
1. Assemble an old 50 mm SMC PENTAX-M type lens, f 1.2; 1.4 or 1.7. These lenses have very large and heavy diaphragms because of their large size. They require a lot of energy to be able to move them. Logic should be in good maintenance and with its clean, lubricated and free movements)
2. Place the camera in M mode
3. Activate the opening ring in C4 menu (28 using opening ring)
4. Select aperture 22 on the lens selection ring
5. Place the camera in LV molding (the mirror is raised and the lens should open its diaphragm to the maximum (1.2; 1.4;or 1.7))
6. Trigger the exposure measurement mode with the green button
7. At that time the diaphragm should be closed to f22 during the exposure time that the processor Determined. (try to do this operation in a dimly lit place so that the exposure time is more or less long)
8. At the end of the exposure calculation the diaphragm must be opened to the maximum again for the LV to be bright. If the diaphragm at the end of the measurement time closes to 22 and remains closed, there is a problem with the lens or diaphragm control.
The equipment then needs to be verified and proceed with its maintenance in case of using these objectives.
Normally with DA type lenses there are no problems because they are more modern and their movements are much lighter and require less energy for their operation.
This maintenance should be carried out logically by qualified persons and I estimate year by year before winter begins.
I think the people of Ricoh know this and that's what they do in their services.
It is important to recognize that cameras with this system are cheaper and for this reason they have components that present these systematic problems, but they also have a degree of equipment and characteristics that distinguishes them from the teams of the competition.
Hoping to have collaborated with a lot of people.

Best Regards

Last edited by sergiogonzalez; 05-20-2020 at 06:44 PM.
04-03-2020, 02:21 PM   #36
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Does anyone know if K70 suffers from this issue as well?
04-04-2020, 09:44 AM   #37
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QuoteOriginally posted by ShawnH Quote
Does anyone know if K70 suffers from this issue as well?
See:
A LITTLE BIT OF HISTORY: Development of the solenoid in Pentax cameras - PentaxForums.com
https://www.pentaxforums.com/forums/193-pentax-k-70/399198-tutorial-repair-p...-solenoid.html
So yes, some K-70's suffer, but since Dec. 2015 the problem was bettered, much less Pentax bodies suffer,

but many K-S1's and K-S2's have been manufactured before already, so those suffer more.

04-05-2020, 09:27 AM   #38
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QuoteOriginally posted by sergiogonzalez Quote
Now to end the problem of dark photos ....
that would be a good idea if it could be brought to an end, of course.

QuoteOriginally posted by sergiogonzalez Quote
I must communicate the following to the Pentaxforum community:
To my post #29 I must add the following observation:[

Repeat: the mechanism of the diaphragm control block is 90% analog and electromechanical and only 10% digital (counter of the windows of the exhaust wheel). It is for this reason that the new Pentax cameras have changed the diaphragm control block to a team commanded by a stepper motor.
Sergio, this is wrong:
Pentax has NOT CHANGED the diaphragm control block into a new version using a stepper motor!
Pentax has introduced stepper motor first time in the K7, followed by the K5, K-01, K3, KP and K1

Those are the semi-professionals.
The consumer cameras ALL had and still have the solenoid as well as those two very rugged and highly praised semi-professionals:
The K10D and K20D!

So the latest Pentax is the K-70 using a solenoid.
And since Dec. 2015 the solenoid now works much better!
Pentax did do some good homework.

Anyway, what you now bring about is all based on pure theory because you have no experience with a Pentax DSLR using the white Japan solenoid:
QuoteOriginally posted by sergiogonzalez Quote
Many components that can be failed are saved.
It was repeated now a 1001 and more times and even works like Aladin's magic lamp:
The white Japan solenoid never failed!
It has been used in various ways in old analog cameras and slightly changed in DLSR 100% successfully in:
*ist D, *ist DS, *ist DS2, *ist DL, *istDL2, K100D, K100Dsuper, K110D, K200D, K-m (2000), K-x, K-r, K10D, K20D
Samsung versions of *ist (GX1 etc) and K10D/K20D as well of course.

ONLY SINCE THE K-30 (i.e. green version made in China) it started to fail!

BUT NOT BECAUSE OFF:

QuoteOriginally posted by sergiogonzalez Quote
When the lubrication of the switch gets old and gets dirty, its contacts begin to introduce interference and electrical noises, in addition the lubrication of the cams and gears suffer the same aging producing the increase in consumption of the electric motor.
These two problems cause the diaphragm control to start to fail and take dark photos, as we explained.
This is just not true!
Based on your insistance stemming from 1 single China solenoid from your K-S2 which for sure you have tried to modify with all your might, and yet: All this stuff about lubrication and electric noice is just wrong.

The reason why the China solenoid fails has been explained and measured, but you do just ignore it, why?

..... [snip]

QuoteOriginally posted by sergiogonzalez Quote
Regarding the most demanding test that can be performed on a diaphragm control block, it is:
1. Assemble an old 50 mm SMC PENTAX-M type lens, f 1.2; 1.4 or 1.7. These lenses have very large and heavy diaphragms because of their large size. They require a lot of energy to be able to move them. Logic should be in good maintenance and with its clean, lubricated and free movements)
2. Place the camera in M mode
3. Activate the opening ring in C4 menu (28 using opening ring)
4. Select aperture 22 on the lens selection ring
5. Place the camera in LV molding (the mirror is raised and the lens should open its diaphragm to the maximum (1.2; 1.4;or 1.7)
6. Trigger the exposure measurement mode with the green button
7. At that time the diaphragm should be closed to f22 during the exposure time that the processor Determined. (try to do this operation in a dimly lit place so that the exposure time is more or less long)
8. At the end of the exposure calculation the diaphragm must be opened to the maximum again for the LV to be bright. If the diaphragm at the end of the measurement time closes to 22 and remains closed, there is a problem with the lens or diaphragm control.
This method is correct, but it can be done much easier by just following this guide:
How to detect aperture block failure on Pentax K-S1 (and K-S2) - PentaxForums.com

QuoteOriginally posted by sergiogonzalez Quote
Normally with DA type lenses there are no problems because they are more modern and their movements are much lighter and require less energy for their operation.
Sorry, but this is wrong as wrong can be!

It has nothing/zero to do with if they are DA, FA, F, DA-L or any other AF Lenses.
The solenoid doesn't have to carry those lenses on its shoulders no does it have to do any extra work with DA lenses!

In most cases when the (green, and only this one!) solenoid fails, people / consumer used DA or DA-L lenses.


QuoteOriginally posted by sergiogonzalez Quote
This maintenance should be carried out logically by qualified persons and I estimate year by year before winter begins.
I think the people of Ricoh know this and that's what they do in their services.
Are you kidding???

Really, people should send their cameras before winter/cold seasons to Ricoh to get them lubed and freed from electrical noice?

QuoteOriginally posted by sergiogonzalez Quote
It is important to recognize that cameras with this system are cheaper and for this reason they have components that present these systematic problems.....
Again, this is wrong: The solenoid has worked without ever failing in all those Pentax bodies mentioned before, i.e. from *ist-D up to the K-r and K20D and all Samsung versions!

Last edited by photogem; 04-06-2020 at 10:04 AM.
04-06-2020, 08:41 AM   #39
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QuoteOriginally posted by photogem Quote
that would be a good idea


WRONG:
Pentax has NOT CHANGED the diaphragm control block into a new version using a stepper motor!
Pentax has introduced stepper motor first time in the K7, followed by the K5, K-01, K3, KP and K1

Those are the semi-professionals.
The consumer cameras ALL had and still have the solenoid as well as those two very rugged and highly praised semi-professionals:
The K10D and K20D!

So the latest Pentax is the K-70 using a solenoid.
And since Dec. 2015 the solenoid now works much better!
Pentax did do some good homework.

Anyway, what you now bring about is all based on sheer theory because you have zero experience with a Pentax DSLR using the white Japan solenoid:

It was repeated now a 1001 and more times (and works like Aladin's magic lamp):
The white Japan solenoid never failed!
It has been used in various ways in old analog cameras and slightly changed in DLSR 100% successfully in:
*ist D, *ist DS, *ist DS2, *ist DL, *istDL2, K100D, K100Dsuper, K110D, K200D, K-m (2000), K-x, K-r, K10D, K20D
Samsung versions of *ist (GX1 etc) and K10D/K20D as well of course.

ONLY SINCE THE K-30 (i.e. green version made in China) it started to fail!

BUT NOT BECAUSE OFF:


This is wrong. Based on your insistance stemming from 1 single China solenoid from your K-S2 which for sure you have tried to modify with all your might, and yet, all this stuff about lubrication and electric noice is just wrong as wrong can be!

Why the China solenoid fails has been explained and measured, but you insist in ignoring it but telling us fairytales!

..... [snip]



This method is correct, but it can be done much easier by just following this guide:
How to detect aperture block failure on Pentax K-S1 (and K-S2) - PentaxForums.com


Sorry, but this is wrong as wrong can be!

It has nothing/zero to do with if they are DA, FA, F, DA-L or any other AF Lenses.
The solenoid doesn't have to carry those lenses on its shoulders no does it have to do any extra work with DA lenses!

In most cases when the (green, and only this one!) solenoid fails, people / consumer used DA or DA-L lenses.



Is this now devoping into some kind of fairytale?
Are you kidding???

Really, people should send their cameras before winter to Ricoh to get them lubed and freed from electrical noice!


again. wrong as wrong can be: The solenoid has worked without ever failing in all those Pentax bodies mentioned before, i.e. from *ist-D up to the
K-r and K20D!
Dear Community:

With this thread, I finish my research (for the good of Photogem) and I will not use too many words.

I've tried to be as objective as possible, so anyone understands.

Everything is explained in the threads #29 and #35

In order to reach these conclusions, it is necessary to understand Newton's law, the Ohms’s law, the management of electrical powers (as generated, how they are transformed and where their losses occur) and the physical properties of the materials used and their relationship with the environment.

You should also be able to understand that the function of the complete assembly, was to be designed and analyzed.

If you are not prepared to isolate the fault, surely everything will be a fairy tale and you don't need to write anything in red letters.

To say that everything is wrong, lets you see clearly the limitations of Photogem.

I hope I have contributed to this community

Best Regards¿
04-06-2020, 10:20 AM   #40
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QuoteOriginally posted by sergiogonzalez Quote
Dear Community:

With this thread, I finish my research (for the good of Photogem) and I will not use too many words.

I've tried to be as objective as possible, so anyone understands.

Everything is explained in the threads #29 and #35

In order to reach these conclusions, it is necessary to understand Newton's law, the Ohms’s law, the management of electrical powers (as generated, how they are transformed and where their losses occur) and the physical properties of the materials used and their relationship with the environment.

You should also be able to understand that the function of the complete assembly, was to be designed and analyzed.

If you are not prepared to isolate the fault, surely everything will be a fairy tale and you don't need to write anything in red letters.

To say that everything is wrong, lets you see clearly the limitations of Photogem.

I hope I have contributed to this community

Best Regards¿
Constructive analysis that’s based on research, knowledge, experience, logic and an open mind- and which then gets successful results, is what is highly sought after and appreciated.
Speaking for myself I can only praise photogem for his contributions, which I believe have helped many and certainly have helped me. His solution has proven itself already.
I sympathize with you
sergiogonzalez that in your area you can’t get parts, also I appreciate your efforts in trying to find an alternative solution, but so far there isn’t one, though I would encourage you to keep trying. Your dedication is commendable.
04-06-2020, 04:15 PM   #41
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QuoteOriginally posted by Walkingwolf Quote
Constructive analysis that’s based on research, knowledge, experience, logic and an open mind- and which then gets successful results, is what is highly sought after and appreciated.
Speaking for myself I can only praise photogem for his contributions, which I believe have helped many and certainly have helped me. His solution has proven itself already.
I sympathize with you
sergiogonzalez that in your area you can’t get parts, also I appreciate your efforts in trying to find an alternative solution, but so far there isn’t one, though I would encourage you to keep trying. Your dedication is commendable.
Dear Walkingwolf:
Thank you for your support and recognition. This encourages us all to move on.
As for solving the problem, I assure you that it is treated in the threads #29 and #35 works.
The Chinese green solenoid has very few electromechanical differences with Japanese white and is well built, and it should be used as the factory mounts
Its just need a little more energy to release it.. Therefore, efficient lubrication and cleaning of the control diaphragm block is necessary to have these energy losses in the solenoid. My Ks2 camera is working perfectly as when I just premiered it, and it proves its efficiency even with my old 78s lenses. (one 28 mm other 50 mm lens and a 70-205 telezoom).
This determines that my investigation is over.
The problem is isolated.
It's a matter of scheduling yourself to do preventive maintenance so you don't have the problem anymore.
It is very easy to lubricate the diaphragm control. It can be done even without disarming the camera, but you have to have an accurate knowledge of where the components are to be maintained and how to inject the cleaners and lubricants, so as not to damage neighboring components; that's why you need to have some knowledge of what's being done.
All machines are machines and sooner or later they will need maintenance. I have worked on this subject all my life, which leads me to infer also that with Japanese white solenoid, sooner or later the problem will appear because it is not his responsibility.
As for Photogem, I have no doubt that its threads have been of much informative use, and have allowed me to know the design of my camera, without having to disassemble it. For this reason, in all my posts I have shown appreciation of his task. But he finds it very difficult to accept other points of view, which in the long run can serve him as well.
We will be in contact within a reasonable period to report how my KS2's diaphragm control continues to be doing.
Honest hugs.

Last edited by sergiogonzalez; 04-06-2020 at 04:20 PM. Reason: tipografic error
04-07-2020, 05:42 AM - 1 Like   #42
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I believe I have to make this very clear (before anybody gives his/her Pentax an slippery lubed entry into exodus):

WARNING:

PLEASE DO NOT USE ANY TEFLON-BASED LUBRIFICATION, canned or not canned and spray it into your Pentax!

EXCEPTION: You want to damage your Pentax!

I have used Interflon Fin Super, in Europe one of the most highly recommended (and expensive "dry lubes" and highly recommended and I have damaged expensive and very sensitive bearings with it, i.e. exudus, beyond repair!
This was a very expensive experience never to be repeated.


It is also highly recommended for sewing machines and I know of 2 women who damaged their machines as well beyond repair.
Now, particular professional sewing machines are very sensitive machines equipped with super precise bearings. And damn: This stuff attacked those bearings beyong repair.


But lets put it like this: If lubing would be a solution, don't you think Pentax/Ricoh would have applied it already?

They haven't and they know why.


So this is very risky and I will not stop warning of .... with all due respect... such real dangerous recommendations.

Anyway: This discussion here is not about pride, not about anything personal.
There is no place for competition here.

Last edited by photogem; 05-13-2020 at 06:50 AM. Reason: Bullfight/hurt pride reference removed
04-07-2020, 08:27 AM - 1 Like   #43
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QuoteOriginally posted by photogem Quote
Then let's make this much more clear, before anybody gives his/her Pentax an slippery lubed entry, i.e. highway to Pentax-hell:

WARNING:

DO NOT USE ANY TEFLON-BASED LUBRIFICATION, canned or not canned and spray it into your Pentax

EXCEPTION: You want to damage your Pentax!

I have used Interflon Fin Super, in Europe one of the most highly recommended (and expensive "dry lubes" and highly recommended and I have damaged sensitive bearings with it, i.e. exudus, byond repair.
Very expensive experience.

It is also highly recommended for sewing machines and I know of 2 women who damaged their machines as well beyond repair.
Now, sewing machines (these days very popular because many... my wife as well... produce cloth-face-mask for themselves, hospitals etc)

are very sensitive machines. Real good ones have super precise bearings. And damn: This stuff attacked those bearings.


It is the biggest nonsense and I will not stop warning of .... with all due respect... real dangerous recommendations.

The way Sergio has continuously ignored important facts and speaks about hurt pride.

But: This discussion here is not about pride, not about anything personal.
There is no place for competition here.
Dear Community and Dear Photogem

First your concern is not minor.

That's why I ask you and the whole community too, information about the parting, (photos, draws, specifications) of the diaphragm control. It would be very useful to also get the technical specification of each of the bearings that Photogem reports that there is in the diaphragm control.

This will allow us to properly select the lubricant.

In my thread #28, which must be read and interpreted in detail, I asked the community to investigate what type of lubricant Ricoh uses in diaphragm control.

In the absence of a response, I decided to apply a line of Argentine-made products, which I use successfully in the maintenance of orbital welding equipment, (true marvel of micro engineering, applied to welding high responsibility pipes in the nuclear industry) (nothing to do with a sewing machine!!)

Add datasheets of the same in the #35 thread.

It is for all this that I always suggested that this intervention should be done by qualified personnel.

Waiting for quick response.

Greetings

Last edited by MarkJerling; 05-13-2020 at 03:16 AM. Reason: Bullfight quote reference removed.
04-09-2020, 07:13 AM   #44
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Jokes aside, I think if sergiogonzales wants to use his lubrication trick to bring the green solenoid back to life, that's his choice. I'm not sure I'd make the same choice.

But the whole premise that the green and white solenoids are basically the same and both have the same propensity to fail, that is just proven to be false.

I want to see sergiogonzales address the one point raised by photogem:

*No white solenoid has ever failed*

Until that point is acknowledged and dealt with, and his initial remarks are revised in the light of it, I can't take anything sergiogonzales says seriously, I'm sorry to say.
04-09-2020, 03:15 PM   #45
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QuoteOriginally posted by ChristianRock Quote
Jokes aside, I think if sergiogonzales wants to use his lubrication trick to bring the green solenoid back to life, that's his choice. I'm not sure I'd make the same choice.

But the whole premise that the green and white solenoids are basically the same and both have the same propensity to fail, that is just proven to be false.

I want to see sergiogonzales address the one point raised by photogem:

*No white solenoid has ever failed*

Until that point is acknowledged and dealt with, and his initial remarks are revised in the light of it, I can't take anything sergiogonzales says seriously, I'm sorry to say.
Dear Christian Rock.
Nice to meet you. I appreciate you reading this thread.
Let's try to use few words.

1-The green solenoid comes from the factory and has been designed by the factory.
2-The green solenoid requires to be unlocked a force of 1.5 N and the white solenoid 1.2 N.
3-The green solenoid takes 10 ms to unlock and the white 2 ms to 7.3 VDC. (no voltage values are specified for Chinese, nor current values for both)
4-The manufacturer (Ricoh) design and select the green solenoid with these values
5-The manufacturer employs and continues to use this solenoid.
6-My KS2 camera worked 4 years without problems with the original green solenoid.

With respect to point 1, the one with the most credit is the Ricoh Engineer who must have had many reasons to increase the unlocking force, do not forget that the kinematics of all the diaphragm control changes every time you change a lens.

With respect to point 2, it falls by its own weight that the green solenoid requires more electrical power to be released than the white.

With respect to point 3, eight milliseconds of difference is infinitesimal from 1/5.5 sec (180 ms) that the shooting cycle requires for a photograph.

With regard to points 4, 5 and 6 are explanatory in itself.

The fact that I affirm that it is necessary to clean and lubricate, has support all the above, and explained too in my threads #29 and #35. Unfortunately, it can't be simple explained.

The fact that someone claims that it is necessary to use the white solenoid only, is just an affirmation that Murphy's law wanted it to be fulfilled. I don't doubt that in most cases it's doing well, but I repeat, at some point it'll fail.

It's not the green solenoid that's causing the failure! This has to work without any modification.

Suppose an extreme case. Damage that completely prevents the conduction of the electric solenoid signal through the mirror switch. In that case, no solenoid will work.

For a solenoid to work precisely and energetically, it needs a square DC signal with the highest possible voltage.

For this to be met, the mirror switch contacts must be in good condition and as clean as possible. In addition, all neighbouring consumptions, such as the electric motor of the diaphragm control, must be minimal, so that the solenoid has that higher voltage. For this it is necessary that all the kinematics of the diaphragm control is well lubricated.
The less consuming white solenoid allows the switch to work with less current and will be below the noise it produces, so it will be more reliable in most applications. It will most likely start to fail when this condition is no longer met, or when the need for greater retention force, such as the one taken into account by the manufacturer, appears.

In my verifications all this reasoning has worked and my camera has returned to work reliably and consistently just like when I was new. I've used the lubricants I trusted and so far I haven't had any problems.

I understand the fears that everyone has at the time of such an intervention, for this reason I have requested help with the provision of plans, photographs and specifications of everything related to diaphragm control, and if possible also logical flow diagrams and electrical circuits.

Others, instead of trying to collaborate, send incomprehensible stories in this type of forum.

As far as I can help.

Greetings

Last edited by sergiogonzalez; 04-13-2020 at 09:19 AM.
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