Author Topic: Nikon D3 DSLR: Partial teardown and attempt of repair  (Read 51619 times)

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Offline TiNTopic starter

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Nikon D3 DSLR: Partial teardown and attempt of repair
« on: May 05, 2014, 01:05:24 pm »
Since my hobbies are not limited only to stockpiling 20-year old Keithley gear, but also photography for fun, I finally got pissed of carrying my primary and only one camera every once I wanted to take picture of something at work lab, and vise versa when I needed my cam at home where all my precision gear lives.

So I decided to catch a bullet this time and bought dead D3 body. It was described as shutter and sensor are ok, but camera does not power on. It was dropped, and comes without anything, not even battery. It arrived just today.

Battery cover is pretty much destroyed and looks like previous owner tried to glue it to body.
No battery, so I will be using 5A AC-DC brick which I modified for DC 13V to power camera.
Overall body condition would be 3- out of 5, but no really serious damages. All buttons, glass, LCDs seem to be OK, and given that it's top-tier single-digit pro grade DSLR, it's designed to survive :)

As expected, when power was applied nothing happed, no magic smoke, nothing on any screens, no reaction to controls.

So, anybody interested to take a look how this will go?
« Last Edit: May 05, 2014, 01:08:08 pm by TiN »
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Offline quarks

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #1 on: May 05, 2014, 01:26:21 pm »
Since my hobbies are not limited only to stockpiling 20-year old Keithley gear, but also photography for fun,

Hello TiN,

same here, I am also a big fan of Nikon "1digit" gear

Good luck with the repair.

bye
quarks
 

Offline Excavatoree

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #2 on: May 05, 2014, 02:13:28 pm »
Good luck from me as well.  I'd love to be able to afford a D3, but I get by with the much higher model number.

I've been amazed at what inoperative cameras go for on E-bay.  I bought a lot of old film cameras, and found one to be working but dented, and one to work except for the light meter, so at least the lot is "paid for."  The rest seem to be basket cases.   

The best items are from consumers or users that don't have the inclination to repair - some of those are just simple fixes.  The worst items are from repair shops or people with repair facilities, especially good repair people, as when they give up on one, it's hopeless.

 

Offline TiNTopic starter

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #3 on: May 05, 2014, 02:23:34 pm »
Same here, would not buy working second camera that expensive, specially considering my D800 already expensive enough :) But could not resist with this D3...pesky ebay is too dangerous, addictive.. and it's full-frame.

Any way, seems luck is on my side this time as well. I found a blown PNP BJT  on DC-DC module. I already opened it up lunch time today, so bought a replacement (2SA2023 PNP 60V 5A) already.

Now replaced it, and bingo, camera now powers on, takes pictures, main LCD works.
Top, viewfinder, and iso lcd aint working, and also it gives "ERR" message from time to time.
But shutter works, sensor works, so far looks promising :)

Shutter count in EXIF is 89K, which is good.

I'll update thread with detailed pics later.
« Last Edit: May 05, 2014, 02:27:00 pm by TiN »
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Offline TiNTopic starter

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #4 on: May 05, 2014, 06:10:41 pm »
Ok, here's worklog/progress for day one.

Service manual for D3, 20MB PDF

Unscrew four screws holding back cover with LCD and controls.



Everything clean and nice inside, no blown parts on main board. Looks like there were no attempts to repair it by previous owner, which is always nice.
Since nothing works at all, and camera unable to power on, first suspect - power supply/converter.

According to service manual - it's on two board assembly right next to CF slots assembly.
Lucky enough, we don't need to take apart camera to gazillion pieces to get access to DC-DC board.



Aha.. That's where magic smoke escaped...
It's A2023 marked TO225 packaged transistor. Based on marking on PCB - it have emitter, collector and base, so we know it's a BJT.
Remembering similar style marking inside of my HP 4263B LCR, it's 2SA2023 PNP, rated 5A 80V.



Went local electronics flea market and was lucky enough to get exact same P/N PNP's.

Now there are two things could happen on such step. First - PNP just died from some power surge or battery short for example.
It could be just a dead PNP, so replacing it will get life back to camera.

Or things could be much worse, and actually some other part got shorted and caused power supply to die. In such gear like consumer cameras, which are
almost completely build around custom ASICs, custom controllers and absolutely no schematics or service information available such scenario means that's
best use from it would be a really expensive pencil holder.

I cut old one first to make job easier.



Let's cross our fingers and try to replace PNP.



Original part on left side, new transistor on right side.



5 seconds with my trusty ERSA iCON, and DC-DC assembly is like new again...

Connect back cover with controls & LCD , check to make sure no shorts or any dangerous parts around, connect DC +13V to DCin jack, and...



Ta-daaa.... Great, no smoke, no noise, it's a lucky day :)



Auxilary LCDs aren't working at this moment, probably some FPC cable got bad connection or no contact (remembering that camera was dropped).

Liveview works, tells us that CMOS sensor, aquisition, digital processing works properly.
Now tried to make couple shots, and got files without problems.

There is ERR message happening after every shot, which can be "reset" by turning off, turn on, and releasing shutter once. Seem like some mechanical issue with mirror assembly, as it's
not returning back to normal state after most of shots. Will take a look on that later, let's check LCDs first..



Remove top cover, as microcontroller board which handles LCDs is on top side...



There it is, small board on right top which have lots of FPC's going to it.



I mean, really lots... :)



Nikon guys are not joking around with flat ribbon cables, have parts and connectors all over them.

Now let's check microcontroller board:

Back:



Top:



No visible damages. I hope it's connectors...

Reconnected everything back again...



Great, now all LCDs working proplerly.
So far so good...

Now hard part - need to disassemble most of camera to get ahold of that mirror locking up issue, as it's barely usable in such condition...



Board with sensor is located under aquisition/processing board.



DG board face:



DG board back:



D3 using six ADI AD9974 signal processors, each of them able to capture 2 channels of 14-bit CCD data at 65 MSPS.
Probably they are capturing data from 12MP CMOS sensor via 12 channels to allow that crazy 9 frames per second camera speed. :)

And back of sensor board:



That's it for today, time for sleep, it's 2.08am already.
Not a bad start.

Youtube:



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Offline quarks

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #5 on: May 05, 2014, 06:20:13 pm »
once again, very impressive work :-+

just in case you do not already have it, latest D3 Firmware is 2.03
https://nikoneurope-en.custhelp.com/app/answers/detail/a_id/55915/~/d3-firmware-update-a-2.03,-b-2.03
« Last Edit: May 05, 2014, 06:25:29 pm by quarks »
 

Offline Vgkid

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #6 on: May 05, 2014, 10:18:20 pm »
Impressive job on the beginnings of a camera fix.
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Offline TiNTopic starter

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #7 on: May 06, 2014, 12:40:22 pm »
Heh, seems all luck was left yesterday.

Day two. Disassembled body more, found two frame damages.



Ear which mounts eye piece thru main magnesium body to front block with lens mount together have one of it's "ears" broken. It was holding there just on nothing and fell apart right away.



Second is a crack on lens mount block.

Magnesium is a light and nice metal for gadgets, but one of it's drawbacks is fact that it's fragile. Seems like this camera had pretty decent impact which caused these damages and likely some mechanical parts to get misaligned.
That could explain why it works fine sometimes, and locks up next time. Lot of tolerances in such precision gear like DSLR are in microns, not even millimeters...

Any ideas, except super gluing whole thing?
I think acquiring another dead D3 to get frame, or even worse getting new frame would cost way more than I would like to spend.

That's it for today...
Looks like it's not as easy as replacing one 1$ PNP transistor here :)
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Offline Towger

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #8 on: May 06, 2014, 12:48:07 pm »
Very nice work.

I had a look on ebay at the price a D3 sells at 'broken'. Over £260 for one which looks like it went swimming in the sea!!!! Madness

http://www.ebay.co.uk/itm/FAULTY-Nikon-D3-12-1-MP-Digital-SLR-Camera-Black-Body-only-FAULTY-/301149664437
 

Offline amyk

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #9 on: May 06, 2014, 01:06:45 pm »
Some advice I found about repairing magnesium says to just glue it. Epoxy would probably work too. It all depends on how much load those pieces have to withstand.

 

Offline Excavatoree

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #10 on: May 06, 2014, 01:17:41 pm »
Very nice work.

I had a look on ebay at the price a D3 sells at 'broken'. Over £260 for one which looks like it went swimming in the sea!!!! Madness

http://www.ebay.co.uk/itm/FAULTY-Nikon-D3-12-1-MP-Digital-SLR-Camera-Black-Body-only-FAULTY-/301149664437

It has salt water corrosion and physical damage.  The LCD is no good. Why did 4 people bid so fiercely on this?  Even if three are shills, why did the high bidder pay so much?  Either one or more people are very stupid, or they know something I don't about corroded, damaged cameras.  What on earth on that thing is worth over 400 US dollars, plus shipping?

Also, why do sellers of items damaged to this extent paste in the advertising for the item as if it were working?  The item as sold meets almost none of those specs, and anyone thinking of buying it is buying it for parts or repair and doesn't need the marketing wank.  It takes up a whole page and is useless for an item like this.  It's like selling a crushed car for scrap steel and adding two pages from the dealer sales literature showing the available colors, engine specs, 0-60 time, etc.
« Last Edit: May 06, 2014, 01:24:52 pm by Excavatoree »
 

Offline rs20

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #11 on: May 06, 2014, 01:34:39 pm »
Fantastic teardown, great pics, :clap: :clap:, more please! I had no idea Analog Devices ADC were used inside these things, let alone a whole array of them.

It has salt water corrosion and physical damage.  The LCD is no good. Why did 4 people bid so fiercely on this?  Even if three are shills, why did the high bidder pay so much?  Either one or more people are very stupid, or they know something I don't about corroded, damaged cameras.  What on earth on that thing is worth over 400 US dollars, plus shipping?

Those ADCs cost $32.63 (at 1k quantity) each, so if you re-ball those 6 chips you've got $120 right there. Now of course, actually getting that much for it on eBay/black market is a pretty tall order, but it makes me think it might be worth quite a bit. Also, the frame might be in good condition, which perhaps would be worth <value of working camera> to the OP. To be fair, I am surprised to see the price go so high as well, but it doesn't seem impossibly ridiculous to me.

Quote
Also, why do sellers of items damaged to this extent paste in the advertising for the item as if it were working?  The item as sold meets almost none of those specs, and anyone thinking of buying it is buying it for parts or repair and doesn't need the marketing wank.  It takes up a whole page and is useless for an item like this.  It's like selling a crushed car for scrap steel and adding two pages from the dealer sales literature showing the available colors, engine specs, 0-60 time, etc.

Haha, I do concur.
« Last Edit: May 06, 2014, 01:42:34 pm by rs20 »
 

Offline TiNTopic starter

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #12 on: May 06, 2014, 01:36:02 pm »
Well, I don't feel comfortable at moment just to glue it. Shutter and motors in camera are quite strong and create lot of vibration.
All those frames are thick for a reason. Need to find a way to reinforce it somehow. :)

As for ebay:

Common rule to stay away from water damaged gear, as water easy get into all unreachable areas and oxidize all exposed metals.
Specially in cameras, which have onboard power batteries, and thus unable to avoid rapid oxidation of all energized paths.
So in 99% cases water damaged electronics is BER, and good only for mechnical parts.

Specs and details probably automatically inserted by ebay, as all camera lots have those specs.
Seller have clear description: Item condition:For parts or not working “Had Salt Water Contamination (SPARE PARTS ONLY)”, so that's what matters :)
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Offline Excavatoree

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #13 on: May 06, 2014, 02:09:58 pm »

Those ADCs cost $32.63 (at 1k quantity) each, so if you re-ball those 6 chips you've got $120 right there. Now of course, actually getting that much for it on eBay/black market is a pretty tall order, but it makes me think it might be worth quite a bit. Also, the frame might be in good condition, which perhaps would be worth <value of working camera> to the OP. To be fair, I am surprised to see the price go so high as well, but it doesn't seem impossibly ridiculous to me.


Wouldn't the salt water bath (without being rinsed off) ruin any electronic components beyond use?   How would one clean the corrosion?  (or are they gold? Again, I offer the caveat that I'm silly and ignorant)  Who would pay 120 dollars for salty chips?  (add fish and some vinegar?)  Even if they were sell-able, that still leaves around 300 dollars to recover.     If I were working on my or a client's camera, I darn sure wouldn't use parts salvaged from the ocean. 

Thanks for the insight.  I do see other "hopeless" cameras go for as much, so perhaps the market for these parts does indeed exist.  Maybe the person who bought this one doesn't realize the problems with salt water corrosion, and simply thinks it's as good of an economic decision as a non-corroded, basket case camera.

Oh, and apologies to the OP for going off on a tangent.

One question to the OP:  Since you are aware of how much work is involved, and how much a working D3 is worth, would you pay 400 dollars for a salty camera if the frame was good? (not that one, it is described as physically damaged and I wouldn't think one would want to risk it) Is the total labor to strip it plus the cost worth it?

A working used D3 is around 3-4 thousand US dollars (if it's not the S model) so I'd say it may be, but I've never taken one apart.
« Last Edit: May 06, 2014, 07:10:33 pm by Excavatoree »
 

Offline SeanB

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #14 on: May 06, 2014, 06:22:23 pm »
The broken mount is fixable with some slow cure epoxy ( something that takes 24 hours to cure and around an hour to gel) like ABE Epidermix. Smells bad, and worse when mixed, but if you clean the parts with acetone and let dry then apply a thin film and align and clamp for 48 hours it is as strong as you can get.

For the cracked frame I would suggest stripping it and then clamping it together and apply a thin superglue and leave for 24 hours to cure. this will wick into the crack and bond it quite well.

I have used the ABE product to fix many things, and generally the bond is stronger than the parent metal.
 

Offline robrenz

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #15 on: May 06, 2014, 06:45:49 pm »
Well, I don't feel comfortable at moment just to glue it. Shutter and motors in camera are quite strong and create lot of vibration.
All those frames are thick for a reason. Need to find a way to reinforce it somehow. :)

IMO  Very carefully clean deburr the break face. This means lightly removing any deformed of smeared areas of the break face that are preventing a perfect re-mating of the granular break. The purpose here is to have it as close to its original location as possible. Degrease the surfaces thoroughly then epoxy with a high strength epoxy that has at least 3000 to 4500 PSI strength. (like scotchweld DP-460) If the epoxy does not state its strength don't use it! Make sure the joint is completely reseated properly and let fully cure. Ideally get some carbon fiber rods from the local hobby shop that are in the .040" to .060" diameter range. Drill several holes thru the joint as close to perpendicular to the break as possible that the carbon fiber rods can slip fit into. Now epoxy these rods into the holes and let them cure fully. Pieces of drill shank could be substituted for the carbon fiber rods also.

Edit:
On the second crack I would lay a piece of light glass or carbon fiber cloth over the crack using the same high strength adhesive to wet the cloth and bond it to the frame.  It looks like there may be a second crack above the long one in the fillet in the upper right hand area.
« Last Edit: May 06, 2014, 06:58:02 pm by robrenz »
 

Offline rs20

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #16 on: May 06, 2014, 11:34:29 pm »
Wouldn't the salt water bath (without being rinsed off) ruin any electronic components beyond use?   How would one clean the corrosion?  (or are they gold? Again, I offer the caveat that I'm silly and ignorant)  Who would pay 120 dollars for salty chips?  (add fish and some vinegar?)  Even if they were sell-able, that still leaves around 300 dollars to recover.     If I were working on my or a client's camera, I darn sure wouldn't use parts salvaged from the ocean. 

Oh, I don't think you'd last long in the budget camera repair game. Adhering to such ridiculous rules is part of what makes genuine OEM service so expensive.  :P

On a less cynical note, though, I'm trying to visualize a BGA chip -- is there any material visible apart from solder ball or plastic? I claim you'd remove the solder balls entirely (and associated corrosion) as a matter of course, and they'd have protected the lands on the chip (either physically or galvanically). Maybe. This is the type of person who reflows the CPU on their Xbox, using an electric frypan, successfully. It's good that we can afford to have the luxury of just rejecting chips in such a condition, but it's worth keeping in mind that us engineers might be more conservative than strictly necessary in that regard.

Chips aside, the viewfinder optics, mirrors, lens mount mechanics, and pentaprism are all probably in good shape after a good clean too. Is there's a demand for these things in the repair world, it all adds up.
 

Offline TiNTopic starter

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #17 on: May 07, 2014, 01:00:39 pm »
Day 3

Thanks, robrenz.
And yes, you have good eye, there is second crack on that fillet edge.



Tested shutter today, it works good. It's the front body issue with mirrors and stuff. I'll have to record a video of full front body part disassembly, as I will never findout after where which screw or pedal goes  :-DD

Bought copycat battery (actually two by mistake  :palm:), noname charger on ebay. Hope I will have camera fixed by time that arrive.

As of buying sunken D3 for 400$, no, that's too much in this repair project. It makes whole thing unreasonable, as used D3 can be acquired for around 2K, without so much hassle and trouble.
And that is not giving even any warranty that frame in that body is okay, maybe it was dropped from helicopter before  :P
Also I belive optics is pretty much destroyed in sunk cameras, as usually there are very thin coatings, which are easy to damage by cleaning/chemicals.

EDIT



Looks scary...



Also I found dodgy diode. It seem to be working, 0.74V Vf, but it was definitely heating up before. Not sure if it's "normal".



Problem is in that chunk of mechanics, aperture/mirror control unit.
One of levers for exposure metering unit was bent, fixed it. Should be some other problem somewhere too, which prevents mechanics to interact correctly.
« Last Edit: May 08, 2014, 01:44:15 am by TiN »
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Offline SeanB

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #18 on: May 07, 2014, 01:14:31 pm »
If the body is a magnesium casting sea water pretty much dissolves it. I saw the photo's taken of an Aeromacchi Impala that crashed into the sea, and which was recovered 2 weeks later. The engine castings ( massive magnesium alloy castings) were basically missing, leaving rings of other metals and rows of bolts held together by locking wire. Once the oxide coat is dissolved the metal vanishes quite fast.
 

Offline TerraHertz

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #19 on: May 07, 2014, 01:24:07 pm »
I'll have to record a video of full front body part disassembly, as I will never findout after where which screw or pedal goes  :-DD

FWIW, when disassembling things with many small screws and parts, my 'memory aid' is to do a very minimal sketch of the mechanics at each stage (just enough to get orientation), then as I remove each screw I stick a bump of bluetak on the drawing in the appropriate spot, and stick the screw in the bluetak. Also write a sequence number on the paper there, so I can reverse the order and not forget anything.
This also prevents losing screws. And the worst thing - when you don't notice that some screws are very slightly different from others, and it matters. With the bluetak trick, they never get mixed up.

Sorry to mention it a bit late for you with this project. But maybe *next* time give it a try.

Another way I've used, is to buy a bunch of little 1"x2" square ziplock bags, and put screws (or sets of them) as I remove them,  in a bag with a postit note giving the sequence number and any necessary drawing or description.
One drawback with this method, is that when buying lots of the little bags I think people suspect I'm a drug dealer or something.
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Offline _Sin

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #20 on: May 07, 2014, 01:39:06 pm »
That's a cracking camera. Pun intended.

Great to see it being fixed though - hate to think of stuff like this ending in up landfill somewhere.
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Offline amyk

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #21 on: May 07, 2014, 01:40:57 pm »
If the body is a magnesium casting sea water pretty much dissolves it. I saw the photo's taken of an Aeromacchi Impala that crashed into the sea, and which was recovered 2 weeks later. The engine castings ( massive magnesium alloy castings) were basically missing, leaving rings of other metals and rows of bolts held together by locking wire. Once the oxide coat is dissolved the metal vanishes quite fast.
Not surprising, given that magnesium is used as a sacrificial anode material.
 

Offline quarks

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #22 on: May 07, 2014, 02:15:12 pm »
if you want to see the naked beauty have a look at att. pic
 

Offline rs20

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #23 on: May 07, 2014, 11:34:45 pm »

If the body is a magnesium casting sea water pretty much dissolves it. I saw the photo's taken of an Aeromacchi Impala that crashed into the sea, and which was recovered 2 weeks later. The engine castings ( massive magnesium alloy castings) were basically missing, leaving rings of other metals and rows of bolts held together by locking wire. Once the oxide coat is dissolved the metal vanishes quite fast.

Devil's advocate: in your example, the engine castings were in contact with steel and a continuous circuit of sea water for two weeks, causing the blocks to act as sacrificial anodes. A wet camera, on the other hand, has the bulk of the water removed in seconds and there's hardly any steel or non-magnesium metal to speak of -- just magnesium, plastic, rubber and maybe some dried-up salt. No complete sacrificial anode circuit, no sacrificial anode action, massively different reaction rate. It's true that sea water is bad news for magnesium alloys for any extended period of time, but I don't see any evidence that a brief splash is going to cause meaningful problems.

Of course, I'm not volunteering to buy sea-damaged gear here. Just debating whether we can be so sure that a bit of sea water is such catastrophic news.
 

Offline maxslug

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Re: Nikon D3 DSLR: Partial teardown and attempt of repair
« Reply #24 on: May 08, 2014, 04:15:41 am »
Awesome job TiN!

We're watching from over at nikon hacker.  let us know if we can be of any assistance.

-m
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