[Lhorn]

I picked up a K-70 last year for $400 with a 96 shutter count. A few months in it developed aperture block failure. It pissed me off because I had to deal with that issue on my K-S2. But, after I calmed down I bought the white solenoid for $45 or so on eBay and replaced it easy enough. Now I have a K-70 I don't need to worry about. It's a nice camera and pretty reliable except for that one issue which may or may not ever happen to you. If it does...it's an easy diy repair.

That’s my plan. Enjoying a new K-70 immensely, but I ordered a white solenoid to put on the shelf just in case. Looking forward to many years of use. I’m half tempted to keep my eyes out for a low $$ K-50 that someone gave up on due to faulty solenoid and fixing it for a backup.

[ramseybuckeye]

Just to buck the trend, I used my K30 every day. It still went! If it’s going to fail, it will fail but the fix isn’t an arm and a leg, £125, ok, it’s a pain but cheaper than a replacement. if you like your camera as I did with my K30 just use it and enjoy it. If you are one of the minority and it fails, get it fixed and get back out there.

Footnotes: 2 weeks after I fixed my KP a nearly new K3 fell in my lap for less than £300 but the K30 kept coming out to play until I traded it in for my KP. I still miss that little camera, it was just so easy to use

I had a K-30 that also had the aperture block failure. I used it daily and put hundreds of shots on it every week. Fortunately for me I had purchase the Pentax extra warrantee and it was covered. While it was out for repair I bought a K-50 while they were at that great price. Down the road the battery hook on my K-50 broke, I sent it in for repair, when it came back the repair order said they also replaced the aperture block, which was not failing. Maybe they seen something, maybe that had just become the standard practice, who knows.

Anyway, I don’t think amount of usage had any effect on failure. A lot of the little used units we heard about on the website were new forum members who only came because they suddenly had a problem.

[tonyzoc]

I had a K-30 that also had the aperture block failure. I used it daily and put hundreds of shots on it every week. Fortunately for me I had purchase the Pentax extra warrantee and it was covered. While it was out for repair I bought a K-50 while they were at that great price. Down the road the battery hook on my K-50 broke, I sent it in for repair, when it came back the repair order said they also replaced the aperture block, which was not failing. Maybe they seen something, maybe that had just become the standard practice, who knows.



Anyway, I don’t think amount of usage had any effect on failure. A lot of the little used units we heard about on the website were new forum members who only came because they suddenly had a problem.

That maybe true. My K-S2 has 600 count and my K-70 has 96 when I got it. Both were over 4 yrs old...so the essentially sat unused.

[PENTAPSC]

I had a K-30 that also had the aperture block failure. I used it daily and put hundreds of shots on it every week. Fortunately for me I had purchase the Pentax extra warrantee and it was covered. While it was out for repair I bought a K-50 while they were at that great price. Down the road the battery hook on my K-50 broke, I sent it in for repair, when it came back the repair order said they also replaced the aperture block, which was not failing. Maybe they seen something, maybe that had just become the standard practice, who knows.

Anyway, I don’t think amount of usage had any effect on failure. A lot of the little used units we heard about on the website were new forum members who only came because they suddenly had a problem.

Could aperture block be ameliorated, prevented or put off "indefinitely| by applying just a tiny half-drop or so of lubricant onto the moving part of this component? I'm thinking of a popular cleaner/lubricant used in electronic equipment for cleaning and lubricating potentiometers or fader switches, such as DeoxiT D5, or DeoxiT GOLD. These products shouldn't otherwise have any detrimental effects on the electronics or plastic components in our cameras, other than making the sliding par of the dreaded aperture mechanism operate more freely and therefore far less likely to seize or jam.

[que es tu]

Well I've failed to win a new camera body so will have to put my hands in my pockets soon, I'm just so cheap

How reliable is the K70? The reason I ask is that the majority on eBay are low shutter count and sold as refurbished? Is it the solenoid issue?

I have a K-S2 with aperture block failure which was manufactured in March 2015. I bought it in Dec. 2016, and it failed in March of 2020 at about 14000 shutter actuations. Personally, I think that my changing lenses is high humidity environments contributed to its demise, as I used it nearly every day. Maybe moisture got in and corroded the plunger?? I replaced it with a new KP which uses a stepper motor for the aperture. After doing research and posting questions on this Forum, I recently bought my son a K-70 for his birthday. It was manufactured in 2019, and I feel confident in its reliability. He shoots with it EVERY day, so the aperture actuator gets a good workout! I hope it will last him 5 years or so. That seems to be a reasonable life span, but if it goes longer that will be great. He is very careful with his gear, where I may have been a little too “cavalier” with my K-S2, in retrospect. The K-70 is very similar to the K-S2 in build, but has more features and better IQ. Also, the aperture actuation sound is much “smoother” and a little quieter on the K-70 compared to the K-S2, so perhaps that is indicative of a modification of the solenoid?? If something happened to my KP, and I did not have the funds to replace it, I would get a K-70.

---------- Post added 12-30-20 at 02:11 PM ----------

Could aperture block be ameliorated, prevented or put off "indefinitely| by applying just a tiny half-drop or so of lubricant onto the moving part of this component? I'm thinking of a popular cleaner/lubricant used in electronic equipment for cleaning and lubricating potentiometers or fader switches, such as DeoxiT D5, or DeoxiT GOLD. These products shouldn't otherwise have any detrimental effects on the electronics or plastic components in our cameras, other than making the sliding par of the dreaded aperture mechanism operate more freely and therefore far less likely to seize or jam.

Someone else on the Forums tried this and they said that the lubricant locked the plunger up due to the surface tension of the oil. They used a Teflon lubricant. I can't recall the Username, but he was from Argentina. Sergio something? I've got it! The title of the thread is: Dark frames or dark expositure problems in KS2, K30, K50, etc. and the OP was sergiogonzalez (the spelling is the OP's)

[BryantCP]

Don't forget sensor stains and mirror flap!


Steve

To Hoya's credit, I think by later production runs they had corrected most of the quality control issues, aside from the issues with certain types of artificial light. I bought my K-5 just a few months before the K-5 II was released and haven't had any issues with it.

[ramseybuckeye]

I have a K-S2 with aperture block failure which was manufactured in March 2015. I bought it in Dec. 2016, and it failed in March of 2020 at about 14000 shutter actuations. Personally, I think that my changing lenses is high humidity environments contributed to its demise, as I used it nearly every day. Maybe moisture got in and corroded the plunger?? I replaced it with a new KP which uses a stepper motor for the aperture. After doing research and posting questions on this Forum, I recently bought my son a K-70 for his birthday. It was manufactured in 2019, and I feel confident in its reliability. He shoots with it EVERY day, so the aperture actuator gets a good workout! I hope it will last him 5 years or so. That seems to be a reasonable life span, but if it goes longer that will be great. He is very careful with his gear, where I may have been a little too “cavalier” with my K-S2, in retrospect. The K-70 is very similar to the K-S2 in build, but has more features and better IQ. Also, the aperture actuation sound is much “smoother” and a little quieter on the K-70 compared to the K-S2, so perhaps that is indicative of a modification of the solenoid?? If something happened to my KP, and I did not have the funds to replace it, I would get a K-70.[COLOR="Silver"]

When my K-30 was repaired the receipt said the aperture block was replaced, not just the solenoid. Is it possible that even though similar and using a like solenoid, they are other differences in the K-70's aperture block? Maybe if someone has disassembled both the K-70 and an older model they may know.

[Bertrand3000]

When my K-30 was repaired the receipt said the aperture block was replaced, not just the solenoid. Is it possible that even though similar and using a like solenoid, they are other differences in the K-70's aperture block? Maybe if someone has disassembled both the K-70 and an older model they may know.

Hi,

You can check by yourself :

Disassembly of K-30/K-50/K-500 : Manual solenoid replacement Pentax K30 / Discharge flash-condenser / Solenoid choice - PentaxForums.com

Disassembly of K-S1 : Manual: Solenoid replacement: Pentax K-S1 - PentaxForums.com

Disassembly of K-S2/K-70 : Manual: Solenoid replacement: Pentax K-S2 (and K-70) - PentaxForums.com

It's about the same for the K-S2 and the K-70, but the K-S2 initially used to have the same weak solenoid. Only later production (December 2015 and forward) used a supposedly stronger solenoid. K-70 is believed to use a stronger solenoid since the start.

Apparently, repair facilities used to replace the entire Aperture Control Block, because they didn't know it was the solenoid only which was faulty. That said, I don't know if they will still replace the entire block for failing K-70 today.

[stevebrot]

Apparently, repair facilities used to replace the entire Aperture Control Block, because they didn't know it was the solenoid only which was faulty. That said, I don't know if they will still replace the entire block for failing K-70 today.

Yes, that is still the case. They also replace another part, something described as a "resistor chip", though its existence has been challenged.


Steve

[que es tu]

When my K-30 was repaired the receipt said the aperture block was replaced, not just the solenoid. Is it possible that even though similar and using a like solenoid, they are other differences in the K-70's aperture block? Maybe if someone has disassembled both the K-70 and an older model they may know.

Good point. Photogem has written extensively about this, and I believe they have seen the guts of the K-30, 50, S2, and 70. Perhaps the whole assembly is improved??