Nikkor 70-200 2.8 E FL lens collar knob stuck

[JillianTG]

Hi guys,

I'm a first time poster to this forum but a long time follower of Steve's youtube channel and was wondering if anyone here could help me with the following problem:

The knob that loosens or tightens the lens collar on my 70-200 2.8 E FL nikkor lens is stuck. So if I want to use this lens on my Wimberley WH-200 gimbal head I can only use it in portrait mode, not ideal.
I'm a 28 year old man that would consider himself strong enough to be able to open most hard to open jars, so a lens collar knob shouldn't be an issue, in theory...
Would love to receive tips or tricks to be able to solve the issue without having to send the lens to a nikon service centre for repair. Would also be interested in hearing what strictly not to try

Thanks in advance, cheers!

 

[DRwyoming]

The knob that loosens or tightens the lens collar on my 70-200 2.8 E FL nikkor lens is stuck. So if I want to use this lens on my Wimberley WH-200 gimbal head I can only use it in portrait mode, not ideal.

That's a strange one, I just checked my 70-200mm E FL and it's just a simple knob on a threaded shaft. I can't imagine what's wrong with it except maybe that it got cross threaded or something got in the threads that gummed it up or maybe it was tightened a lot when cold and then things expanded when it warmed up. I don't think there are any tricks though I'd avoid things I'd try on other stuck bolts like heat or solvents and if you use any kind of tool to grip the knob like pliers I'd pad the jaws with soft cloth and if it doesn't loosen up pretty easily I'd think seriously about sending the lens in for repair.

Good luck

 

[Warren D]

What DR said. I'd use slip joint pliers and wrap a rag around it first. If that doesn't free it up, I'm not sure what is going on. I've never had one of those get tight, usually the opposite. Not to be insulting, but you are turning it the right direction? (CCW) I've had memory lapses with the lens caps and tightened them when I wanted to take them off.
I'd avoid heat, at least anything with a point source and anything above 110F. I've put gear in the fridge to help loosen stuck filters.

 

[bleirer]

That is odd. Has it been working normally and now suddenly there is a problem? Had it been completely removed in which case you might suspect cross threading? One trick I used to use on stuck car lug nuts was to tighten it slightly first, then loosen. Are you sure it is supposed to be rightly tightly lefty loosy and are you turning the right direction? Either way a little leverage with a tool, but don't crush it enough to deform the insert or break the plastic.

 

[fulltimewanderer]

Recommend trying a “strap” wrench made of either canvas or rubber.

 

[MYount]

I'm not insulting your intelligence whatsoever. If the barrel is facing toward you the screw turns to the left to loosen. If the barrel is facing the other direction it turns to the right. If that turns out not to be the issue try a little drop of sewing machine oil or something like that and put around it around the base of it to let it soak down into it. Just make sure you leave all your caps on and don't get something that's going to put a lot of oil. If that doesn't loosen it it's probably cross threaded. Then you'll have to use one of the methods with covering it with a thick cloth and using fine jaw pliers.

 

[JillianTG]

Thank you all for your replies! Managed to solve the issue by combining some of the advice written above.

Solution:
I put the lens (with body attached) in the fridge, in a closed off tupperware to prevent most moisture from getting in (only put it in for an hour or so). When I took it out the lens wasn't too cold (its usually way colder when out and about on a stroll during cold weather). Then I used pliers with a washing cloth (any will do if anyone reads this in the future) between each side of the pliers and the knob and managed to easily undo the very tightened knob.

For anyone having the same issue I recommend trying the plier and soft cloth technique before putting it in the fridge, I didn't. Maybe it's not even necesarry. I did try it with my bare hands once again when I took it out of the fridge, which still didn't work so maybe just the plier technique is enough.


Thanks DRwyoming and Warren D for suggesting it being tightened during cold conditions and putting it in the fridge to recreate those conditions.

maybe it was tightened a lot when cold and then things expanded when it warmed up.

I've put gear in the fridge to help loosen stuck filters.

Thanks to basically everyone else for recommending pliers and soft cloth!

Edit: and don't worry to the people questioning if I was taking into account lefty loosy, righty tighty. I'm here for a solution so if a dumb tip would've got the deed done I'd be a happy man too.

 

[DRwyoming]

Glad it worked!

 

[MartyD]

I have noticed that the knob on the collar on my 70-200 E FL seems to get really tight as well. It has many times been a struggle to get it to loosen.

I am glad you got it loosened but isn't it best practice to heat threaded items to get them to loosen? I always thought the physics behind heating is that the nut and bolt both expand but the space between them also expands. Maybe this is one of those myths that I have been living with my whole life.

 

[DRwyoming]

I am glad you got it loosened but isn't it best practice to heat threaded items to get them to loosen? I always thought the physics behind heating is that the nut and bolt both expand but the space between them also expands. Maybe this is one of those myths that I have been living with my whole life.

Heating can work as can cooling but personally I wouldn't apply a lot of heat directly to a lens full of optical assemblies. Sure, if you're talking about a stuck bolt in your car's suspension system heat applied directly even using a torch can be a great way to go but I'd avoid that when dealing with lenses.

If the collar knob actually was tightened a bit too tight on a very cold day and then the lens warmed up then cooling the entire system makes more sense than applying additional heat. Hard to know if that was actually the problem here but cooling the lens down (and that was smart putting it in Tupperware) is a safer bet than heating the bolt up a lot.

 

[Warren D]

I have noticed that the knob on the collar on my 70-200 E FL seems to get really tight as well. It has many times been a struggle to get it to loosen.

I am glad you got it loosened but isn't it best practice to heat threaded items to get them to loosen? I always thought the physics behind heating is that the nut and bolt both expand but the space between them also expands. Maybe this is one of those myths that I have been living with my whole life.

I've considered these things in the past. My logic is that the lens barrel is larger than the threaded stud the knob is on. Normally, heat expands and if, as DR points out, you can apply heat to just the offending stud, that should do the trick. However, with the size of the lens barrel compared to the short stud, cooling the lens and shrinking the barrel seems to make more sense. I know that method works great on stuck filters.

 

[jeffnles1]

Glad it worked. You may want to put a single drop of oil on the threads so it doesn't seize up again. Anti-seize would work too if you have any around your house.

 

[joe43]

I had a problem (different from yours) with the knob on my Nikon 500mm f5.6 pf. Nikon service fixed it under warranty. I suggest you contact Nikon service and tell them about the issue. They might be aware of it and have a replacement part you might need to prevent future problems. Service is pretty quick if the needed part is in stock.

 

[fulltimewanderer]

If you have had any thoughts about arca swiss tripod mount. You might think about replacing the the tripod collar and foot from someone like Really Right Stuff.