Nikon 180mm 2.8 lens: Disassembly
Transcript
Hello everyone, this is Jim from International Camera Technicians and today we’re going to go ahead and take care of this Nikon lens here.
This video is by request
What we’re going to do is we’re going to take it apart. A few people have asked me if I could take this apart and show them how it comes apart, so that’s exactly what I’m going to do. This lens is no longer repairable. I bought it for a junk piece. I had to buy an element not a front element but second element in. It was pretty messed up, on the lens that I repaired. This one had a good one, so I swapped them out. This one doesn’t have a tag on it. This is a 180mm 2.8, it’s the AF version.
It’s a coupler there. I don’t know if it’s the “D” version or the first version, because there’s no name tag, but when we pull the back off, we will see because it’ll just be a different circuit board.
So… what we’re going to do is get going on this thing, I’m just going to strip it all down. And then another video will probably put it all back together. Like I said, this one is missing a few things. It’s got a bad, there’s no click stops for the diaphragm. Diaphragm is opening and closing but yeah, generally this lens is in pretty bad shape. But let’s see how it comes apart, so we’re going to take it apart
Remove the outer element
First of all we start with the screw right here. It’s a set screw, people call them grub screws. Go ahead and take that out. Okay now when you get the element out and — I didn’t get all my tools all set for this, so nothing’s neatly laid out. I will have to search for all my tools, which right at this moment, I don’t seem to have my wrench to get an element out. (Nope, there it is.)
Okay, the [wrench] tips are in, go ahead and spin this front element out. Okay, next time I’ll probably be a little more ready for doing a video.
I didn’t think I put the front element in very tight; I didn’t really need to. I go ahead and [uses tweezers to loosen around the element].
[Holding lens with the element facing down toward the palm] this side down. There’s my element. Kind of sounded nasty, but I didn’t scratch the element. This is actually still a good front element. Put that off to the side.
Remove the second element
Okay so now the next step is to get those three screws down inside there [inside barrel].
One, two, three. Kind of a long shot. [I use] a screwdriver on it, so I get my longer tip screwdriver. They [the screws] tend not to be in too tight, so there’s never really been an issue with stripping these screws out. Two screws out, and the third one down here. And there it goes.
If you need to remove the hood
Okay so this [lens] comes pretty much in half. Put that [the focus assembly] aside for now, if you want to get this hood off, because it’s bent or anything, you do need to take out this outside ring here. A little more difficult to get out; those things are usually on pretty good.
You can do a little more disassembly. This thing is kind of ugly looking.
Get underneath the leatherette, but you can see you need to peel the leatherette to get this system apart, so I’m just going to set that aside. I don’t need to get into that.
Next, remove the rear mount
So, we have here — this is your focus system right here. [Twisting the focus in and out] you can feel how, you can hear how bad that is. This system will kind of pull up a little bit and we’ll take care of that later.
Put that back; let’s go ahead and get this rear mount section off. No problem on the rear mount.
Always on the Nikons, take off these — they’re called mount rings. Take them off first. Very few of them come off with the mount. So… you want to get this mount ring off first.
This will also start to tell me which version of this lens it is. Okay so that did not come up all the way; don’t force this out. I guess this is the first version of the lens.
[Pulling interior section out] whatever it is, this just comes through. Because it didn’t want to pull out, it just didn’t want to pull out because of this [circuit board] flex.
So that’s the circuit board. So this is the first version; it’s not even a “D” lens, but the “Ds” and the non-“Ds” are identical. Just a different circuit board and I think there’s one little contact.
Then take the mount off now it has five screws. One, two, three, four, five. Third one, fourth one. And the fifth [screw]. That pretty much falls off. Nothing underneath the mount really.
There’s your focus coupler. Get that guy up; it’s a good focus coupler.
Okay, so I’m kind of interested to find out what’s going on here.
Remove the f-stop ring
So that connects to the diaphragm. Weird, the click stops, what makes the click stops is here, it fell out, so it’s like someone went in and took the screws out.
The cheap ones have plastic rivets. Yeah — so this one is very unusual to see. This one has plastic rivets on it, classic rivets broke.
You can re-drill them and put screws in it. Put little, short screws, maybe slightly smaller than these. That’ll hold it in place. That’s what I was doing to make this a functional lens. You know I’d find even a screw smaller than that. So, the f-stop ring is good.
Remove the next set of rings
Alright let’s get on with it.
This ring here is going to come off. It’s got the lock on it. Don’t pull the lock out. You pull the lock out and you’re going to end up with 50 parts. [It’s a] little spring, the spring goes in ONE way and one way only. Okay, it’s got a sharp edge here. This one down here actually has a turned-up edge, extremely hard to see. But let’s see.
So I don’t know if you can tell on the video or not, but that’s a turned-up edge and that’s the sharp edge. It just ends. That [sharp edge] goes up into the button. So, it’s kind of like a ski here. Just get smooth lip, otherwise you will kind of dig and scratch into the system. Sorry, you will dig and scratch into this metal, I mean plastic, right here.
And that’s never good.
So, I’m going to go ahead put that on, and put it on correctly. [It] goes on this way. Little bent part [should be] at the bottom. Underneath, push it in, until it clicks. Yeah, probably didn’t hear it, I heard it, one click. It’s in there.
Remove the system
Okay so go ahead and take the system off here. Three screws.
Alright last screw. Okay this will start to come out. It’s tight. I don’t want it to come out here, let’s get this okay. Work it up. Push up [gently through] the screw holes just a little bit at a time. Boom. Popped out. You can’t get it in backwards; you have that cut out [points to notch] with that cut out [points to groove].
So, it’s not going to go anywhere else. It’s got to go in there. Not a problem.
Disassemble the front of the lens
Alright so that’s pretty much everything. Now we need to attack the front,
So alright unless you want to do a bunch of collimating, guessing, you can see that this ring here is put on with tape; the tape starts here. Tape is extremely good for holding lenses together.
Okay I like to bring it all the way up to the front. This is how I keep things straight, go straight down the center and I put this scratch. That’s it.
And put this back together, mark those up. Boom, I know I’m pretty dang close, so close I don’t really have to worry about it. It’s rare that I would have to do any other adjustments.
Mark the guides
Okay so this guy gets pushed back and this guy pulls forward. I’m sorry — wrong, wrong — there’s the access hole there. Since you know where this mark and this mark go, it doesn’t really matter where you take this off at, but you do need to mark where it comes out. (I think that screwdriver is dull.)
So, take the guide out; there we go — one guide. Okay so that guide came out. Now what I want to do is I look where the guide came out from, and I put one little dash mark, the guide that it was in another dash mark, in the area of the tube another dash mark.
I know you probably can’t see all those, but every one has a little dash line. Now I know what direction this element goes in, I know where this ring goes, and I know where the main tube underneath is — all lined up without guessing anything. Boom; done.
Now, it’s got two of these [access guides] — one on the opposite side, go the other one. Align it [the tube] to a position where you can take it out. These are usually pretty tight. (I don’t like this screwdriver. There’s no handle, there’s no grip.)
Okay that guy [the screw] comes out. I can just essentially take the whole tube out. You see back there, there’s my guide marker right there. My scribe marks.
Remove the cam ring
Alright so now I get to take these keys out. That’s your slop adjustment key — your slop adjustment screw — right there. Let’s get the keys out. These may be super tight; they can be anywhere from tight to incredibly tight.
That was easy enough. I’m bearing down pretty hard when I put my screwdriver in. I’m trying to just barely lightly put it in. I’m going all the way down, putting some weight behind it when I turn my screwdriver. You can use some acetone, or alcohol is probably better, to dissolve the glue but just didn’t need it. I don’t really care which side has my key on it, but I will mark this one more towards the front. A little scratch mark, just in case if they’ve kind of worn into each other.
Remove the outside barrel
Alright, now, this has three screws. I think you can get this in almost any direction you want to, so the best thing to do before we pull this off — give yourself a mark that tells you where the front of the lens is. Even if it’s not difficult to align, it just makes it so much quicker when you put things together. Okay so that’s out.
Remove the outside last element
We’re getting to the point where a lot of people are wondering, when they have focus problems — it’s this gear up here; it breaks.
So, what you want to do is take this front [ring] off. Now these [screws] are tight, always tight. Now this guy will come out.
Alright, this is just an element, you see someone scratched it. I don’t know how they reached in that far to scratch it, but they did. This [lens] here had the front element that was the element that was bad because I replaced the element on the other another camera [lens], so this is a junker lens. I think I said that right at the beginning.
Check for a broken gear
There’s your diaphragm sitting right there; nice and pretty.
That’s the gear that breaks a lot. This gear breaks an awful lot, because people don’t take this thing out of auto-focus when they decide to manual focus it and it will turn, it will turn this whole system. This gear will turn and take a tremendous amount of stress and it shears this pin off.
So, the one [question] I saw on Facebook, people asked me to take it apart, they’re complaining that this gear is broken right here. Really what happens is the shaft right here at the end comes loose —sorry, breaks off — so you got to drill. The last one, I drilled. I drilled that shaft into this gear. Started right about here, it went all the way and I dimpled it into this piece of metal up here. And that way that shaft wouldn’t ever pull out we had an anchor point here, the gear and up here.
Remove the diaphragm
Okay so the next thing we do is get the diaphragm out of the way. Let me take a look at that gear a little closer. Most people think this gear breaks; that gear does not break.
It’s actually kind of rare that this thing breaks.
I think I’ve seen one — no, none on this one. On other lenses I’ve seen that break, but not on this particular lens. And you can see the gear — see, here to here. See, it just takes a lot of disassembly to get this gear out of here. People think they can just take the back off and boom — hey, I get the gear out. No!
Watch for the reassembly video
And here we go, I’m going to end here. I don’t want to make this video too long and then I’ll start doing another reassembly.
Alright well, thank you for watching! Please subscribe. I appreciate it. Leave any comments below. [If you have] any questions, let me know.
Essentially, I’m done for now and I will see you in the next video.
Take care; bye.