Bad luck!

[bjornthun]

Here is a thread from dpreview with another damaged D810.

http://www.dpreview.com/forums/post/55639396

It seems there is some "plastic" in the construction, and that the D810 may have changed from the D800.

[Erik Lund]

I did open it - The D810 is a plastic camera,,, Very disappointed!

[simato73]

Wow!
Very surprised...
I thought it was essentially the same as the D800 - at least physically - with improvements in the sensor etc.
I guess this is one place where we can see Nikon has been cutting corners to reduce their manufacturing costs to keep their business afloat.

[Erik Lund]

Indeed!

And It has an impact on how to handle the camera especially with larger/heavier lenses.

Don't put any stress on this mount!

The difference is huge IMHO, you can see it clearly in the linked images on DPR that Bjørnthun posted.

On the D800 the magnesium body shell goes all the way under the mount and stabilises and stiffen that area completely and most of all, the screws that hold the mount has something to bite into a solid metal casting, on the D810 the four screws barely stays put in the plastic, when I unscrewed them they where as loose as expected from self tapping screws seated into plastic, no wonder the camera is so cheap,,,

[armando_m]

Indeed!

And It has an impact on how to handle the camera especially with larger/heavier lenses.

Don't put any stress on this mount!

The difference is huge IMHO, you can see it clearly in the linked images on DPR that Bjørnthun posted.

On the D800 the magnesium body shell goes all the way under the mount and stabilises and stiffen that area completely and most of all, the screws that hold the mount has something to bite into a solid metal casting, on the D810 the four screws barely stays put in the plastic, when I unscrewed them they where as loose as expected from self tapping screws seated into plastic, no wonder the camera is so cheap,,,

...  the D800 magnesium chassis has very weak points on the bottom plate mounting structure, making it necessary to be careful when handling the camera when mounted on a tripod, ie: moving the camera/tripod. Leverage applied to the camera base may break the chassis.

[Bernard Delley]

  I had the D610 mount get pulled out when the 70-200 f4vr hit the door of my jeep...  so I sent it to Nikon.  The mount cost almost nothing but that was the only damage.  ... Something to be said for the plastic mounts.

I hope your insurance does cover it.
All the best,
Tom

I learned two very interesting things in this thread:
- some heavy pro lenses have a breaking point near the bayonet -- and that this can be repaired (sometimes)
- a plastic mount on a retro design camera !! and on D810 -- and that this can be repaired (sometimes)

of course something will give in on mechanical overload. The question is how this should bode with precision equipment.
Metal tends to get a plastic deformation, or break. Plastic tends to go from the elastic regime straight into breaking.
So if its a designed breaking point with easy repair, it could be acceptable, provided it does not break in normal use! And normal use can involve some banging into obstacles in street, event or nature  photography.

The D800 is metal, but Thom Hogan has observed that it is not as forgiving in abuse as the D700.
I accidentally dropped my D800 with a 135mm DC  about 10cm onto concrete. I only found a minor new scratch on the lens hood and no evidence of the mishap on the camera.So I forgot about it soon. Focus was as before.  The often very large, even  off scale,  AF fine tune values needed on my D800 finally got it to Nikon service for alignment. They diagnosed minor impact damage on the mount as part of the issue.  They obligingly replaced the mount for free. Thanks!

[Bjørn Rørslett]

.... I get my supply of spare F-mounts from the local Nikon repair techs, who obligingly put the sheared-off rear part of the 24-70 into a collecting box for me. Must have got at least 10 such items over a couple of years. These lenses are designed to break in a specific manner once the mechanical stress gets too high and would inflict heavy damage to lens or camera, or both, unless something yields under the load.

The sheared parts of the 24-70 include the rear element, which conveniently doubles as a loupe on my work table, the F-mount itself, and the contact block with the torn signal cable.

From experience I can tell these lenses do not break under "normal" use thus no need to fear your own lens being split into two parts.

[Bernard Delley]

.... I get my supply of spare F-mounts from the local Nikon repair techs, ...

sounds like you are joking!  You are  talking about lens  mounts, not camera body plastic-backed mounts ? I seemed to understand that your broken  Df  was gone for good, unlike my understanding of the quote on a D610 in my previous post.

[Bjørn Rørslett]

No joke. I'm dead serious about this. Just pulled out a few 24-70 mounts from the nearest bin. They are shown in various stages of disassembly below. The one to the left has the rear lens shroud still attached, whilst the others have had that removed. All are emptied of their contact blocks as these items have been recycled (by me) long ago. I left a little dust on the lens surface so the viewer can appreciate its existence.

(by the way, this is a jpg straight off my D500, shot at ISO 25600 and only resized....)

[Frank Fremerey]

I use primes only but change them quite often. I have worn down a lot of F mounts both camera side
and lens side and NPS replaces them
not for free but for a little contribution. There are several...

[Bjørn Rørslett]

These mounts weren't worn out Frank, they were sheared off their host lens.

By the way, ever since the longer lenses got steel inserts around the groove for the locking pin, they wear much less.

[Frank Fremerey]

Will you do some writing on the D500?

[Bjørn Rørslett]

Will you do some writing on the D500?

Maybe. Not decided yet.

So far, only tested the efficiency of the built-in UV-blocking filter, which is excellent (at least 12 stops).

[pluton]

I left a little dust on the lens surface so the viewer can appreciate its existence.

Snap! 

[David H. Hartman]

I just read a reply to a thread I started on Flicker's D800/D800E/D810 User's Group. A camera bag drops two feet (0.6m). The AF-S 24-70/2G ED won't focus the next time the camera is used. It work fine on the owner's D800 but not on his D810. A $700.00 (USD) repair for a cracked mirror box.

The owner will no longer store his D810 with a lens on it. I'm thinking I'll store my dSLR(s) only with short lenses, e.g. AF-S 50/1.8 G. Dose this seem too cautious? I don't own a camera with a plastic mirror box. I have frequently stored my D800 with an AF-S 105/2.8G ED VR Micro on it.

Dave

I think of the D810 and D500 as professional cameras and the plastic mirror box and its short screws as an engineering defect. Unfortunately I feel Nikon needs a lot of bad press for these failures.