[nihonsuki]

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One of my part time jobs in college was fixing pinball machines. These are basically dozens of solenoids and relays. If a solenoid is binding it is usually because of misalignment due to improper installation or wear of the mechanical linkages causing misalignment or swelling of the sleeve around the plunger. Swelling is mostly due to overheating of the coil but could be caused by defects in the materials or lubrication by substances incompatible with the material of the sleeve.

Sanding or polishing the plunger is only a temporary solution at best as there is also wear to the sleeve. This wear is more often than not uneven. Without addressing the misalignment issues you'll get further increased wear and malfunction. Without addressing the wear issues in the sleeve and change the tolerances by sanding/polishing the plunger and/or sleeve you'll get further increased wear and binding.

Sure, we would sand and lubricate these parts but only as a temporary stop gap solution to get the machine up and running (and making money) long enough for us to get the parts and replace them.

As I understand it, the problem is not side clearance of the plunger, but the length of the arms and clearance with the magnet. Shortening the arms ever so slightly seems to prevent the plunger from sticking to the magnet.

[athlonus]

Interesting:

Pentax K-30 K-50 Genuine Aperture Solenoid Plunger - Made in Japan - | eBay

[albertoM]

See this page... Figure specifications of the solenoid..... 6 v.....

Taiwan Magnet Solenoid from Linkou Dist., Manufacturer: Summit Elec-Tech Co. Ltd

4 AA - 6v.

lithium battery 7 v.....

coincidence?? That's why it works better with AA?? it is a question....

[HarisF1]

I'm also selling mine - £35 + PnP. Taken from a K-x.

[The Squirrel Mafia]

Latest K-50 Firmware Update : Software Downloads | RICOH IMAGING

^ New firmware update for the K-50. It won't solve aperture control block problem, but this will now give a new lease on life with future KAF4 lenses that have electronic aperture control in the lens. There is only one KAF4 lens at the moment, though.

My guess is that they might release a firmware update for the K-30 too.

[Jochenk]

The bottom line is that we simply do not understand this phenomenon. Some people are reporting its cropping up after the camera was left idle for a period of time.

I had the same issue today after my K-50 was idle for a couple month. I found a tip in an UK forum that suggested to de-activate the trigger lock in the menu and do a couple shots without any lens mounted. I did a few single shots without much luck. Put it on sequence shot and let her rip for a few seconds. I noticed that the sequence got increasingly faster so something kind of worked itself free. After that.....all is good. The aperture works as advertised again.

I am still debating to treat myself to a K-1 if I can justify the cost. Like the GPS on that plus the fact that I need a reliable camera when travelling extensively without ready access to replacement for weeks.

[HarisF1]

Another temporary fix would be to take F and FA series lenses with you in order to have the manual aperture when required.

[albertoM]

Another arrangement is to use AA batteries ... there are people who have worked for you. I have not yet had the problem of the diaphragm ... and I only use AA batteries

[Jochenk]

Another temporary fix would be to take F and FA series lenses with you in order to have the manual aperture when required.

Update: The fix is really temporary at best. It is stuck again. Wrote Ricoh "customer care" but do not have much hope as the camera I way out of warranty.

Does anyone have experience with PC35 Photolab's repair? it costs less and claims to be a more permanent fix than The Pentax repair which replaces the control unit basically with the same, making it another play with the odds....

[Not a Number]

Update: The fix is really temporary at best. It is stuck again. Wrote Ricoh "customer care" but do not have much hope as the camera I way out of warranty.

Does anyone have experience with PC35 Photolab's repair? it costs less and claims to be a more permanent fix than The Pentax repair which replaces the control unit basically with the same, making it another play with the odds....

https://www.pentaxforums.com/forums/189-repairs-warranty-service/334112-k30-a...-repaired.html

It would be interesting to mark the components in question before sending it in to see what he replaces or otherwise makes modifications.

[athlonus]

Update: The fix is really temporary at best. It is stuck again. Wrote Ricoh "customer care" but do not have much hope as the camera I way out of warranty.

Does anyone have experience with PC35 Photolab's repair? it costs less and claims to be a more permanent fix than The Pentax repair which replaces the control unit basically with the same, making it another play with the odds....

You may send it to me for a permanent, fair and honest repair if you wish.

Frequency of my dark screens seems to increase when LV is used and/or shutter delay, so maybe if the power is lower it struggles to fire the aperture?
I can just about retrieve the images if shot in Raw, but I'm selling my K30.

[niceshot]

Frequency of my dark screens seems to increase when LV is used and/or shutter delay, so maybe if the power is lower it struggles to fire the aperture?
I can just about retrieve the images if shot in Raw, but I'm selling my K30.

Hate say this, but it sounds like the shutter block is malfunctioning

Hate say this, but it sounds like the shutter block is malfunctioning

That may well be right. Same component ???

[niceshot]

That may well be right. Same component ???

No two ,completely different items. One is the mirror motor controlled by that solenoid and the other is the shutter block which is responsible for the raising of the shutter curtain.