# 2x Extenders - Sticking Lock Switch



## mackguyver (Jan 14, 2014)

I'm wondering if anyone else has had issues with the 2x extenders - both Mark II and Mark III sticking. The locking switch and/or pin sticks on them and prevents the lens mount from locking. This is really disconcerting with thousands of dollars attached to the end of it. 

What happens is you twist your lens on until it clicks and all seems good. Then you touch your lens and it begins to twist off the extender or you get an error saying to clean your contacts. Either way, the lens is not secured! The pin/switch move, but I guess it gets stuck around 90% of the way to the full lock position and doesn't lock completely.

I had read that the Mark III was supposed to fix this, but my 300 f/2.8L IS II nearly bit the dust the other night due to this issue. A tiny drop of WD-40 took care of it, but I've never had this issue with the 1.4x Mark II or III and find this really disturbing. Has anyone else had this issue?


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## Eldar (Jan 14, 2014)

mackguyver said:


> I'm wondering if anyone else has had issues with the 2x extenders - both Mark II and Mark III sticking. The locking switch and/or pin sticks on them and prevents the lens mount from locking. This is really disconcerting with thousands of dollars attached to the end of it.
> 
> What happens is you twist your lens on until it clicks and all seems good. Then you touch your lens and it begins to twist off the extender or you get an error saying to clean your contacts. Either way, the lens is not secured! The pin/switch move, but I guess it gets stuck around 90% of the way to the full lock position and doesn't lock completely.
> 
> I had read that the Mark III was supposed to fix this, but my 300 f/2.8L IS II nearly bit the dust the other night due to this issue. A tiny drop of WD-40 took care of it, but I've never had this issue with the 1.4x Mark II or III and find this really disturbing. Has anyone else had this issue?


I have never experienced that with any of mine. I have had the 1.4x/2x in both version II and III for years. But it might be that I have not been very attentive. Will be in the future!


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## mackguyver (Jan 14, 2014)

Eldar said:


> I have never experienced that with any of mine. I have had the 1.4x/2x in both version II and III for years. But it might be that I have not been very attentive. Will be in the future!


I'm glad it hasn't happened to you, and yes, it's certainly worth a quick twist to make sure it is truly locked.


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## neuroanatomist (Jan 14, 2014)

Had the 2xII, have the 2xIII, haven't had anything like that happen (and I hope I never do!).


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## jhpeterson (Jan 14, 2014)

I've had this happen, too, on both my 1.4 and 2x extenders (both models II and III). Then again, I work on the ocean, where things like this are to be expected. So, every couple weeks I put a bit of anti-corrosive (in my case, Boeshield/T-9) on the lock as well as both mounting surfaces, giving special attention to the locking pin. I then wait a few minutes and wipe all but a thin film away. While the problem doesn't entirely disappear, it becomes much more manageable; I have enough other surprises in my line of work. 

Of course, having heard the horror stories of friends' big white lenses dropping into the sea, I still double-check to see how well the lens locks in place!


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## surapon (Jan 14, 2014)

Dear Mr. mackguyver
Sorry to hear that---But I have Both 1.4X II, and 2X II for many yeas, and do not have any problem at all.
Just 1 Question, Sir. When you store your equipment= How do you store. In my case, I store in my home , the Place that have Humidity = 45-50% MAX ( Both A/C and Heating Area). BUT-40 years ago, I came from Thailand to Study and Live in NC., USA.---In Thailand have 90-100% Humidity 9-10 Months per years, And In that Time, We do not have A/C system = I had a lot of problem of my Sticky Shutter of my Film Cameras.

Yes, Please use your Humidity Meter to check your Humidity at your equipment storage area---If Higher than 75% = Trouble. But You can DIY. Dry Box to keep your Lenses and Cameras.
Good Luck, Sir.
Surapon


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## mackguyver (Jan 14, 2014)

jhpeterson said:


> I've had this happen, too, on both my 1.4 and 2x extenders (both models II and III). Then again, I work on the ocean, where things like this are to be expected. So, every couple weeks I put a bit of anti-corrosive (in my case, Boeshield/T-9) on the lock as well as both mounting surfaces, giving special attention to the locking pin. I then wait a few minutes and wipe all but a thin film away. While the problem doesn't entirely disappear, it becomes much more manageable; I have enough other surprises in my line of work.
> 
> Of course, having heard the horror stories of friends' big white lenses dropping into the sea, I still double-check to see how well the lens locks in place!


Thanks for sharing your experience and tips. I live in humid Florida and shoot near the ocean a good deal of the time so that's probably the culprit. It's odd that my 1.4x extenders have never been a problem, though, but maybe it's just a matter of time. 

Also, I can't imagine the feeling of dropping a big white into the sea - wow, that's a terrifying thought!



surapon said:


> Dear Mr. mackguyver
> Sorry to hear that---But I have Both 1.4X II, and 2X II for many yeas, and do not have any problem at all.
> Just 1 Question, Sir. When you store your equipment= How do you store.
> Good Luck, Sir.
> Surapon


Surapon, I store my gear in my climate controlled house and my hygrometer is usually between 50 and 60% humidity. The locations I shoot in are always between 80 and 100% humidity, though, and with "salt air" near the ocean. I guess these little pins are more sensitive than other components. Maybe Canon can gold plate them in the Mark IV extenders


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## ichetov (Jan 14, 2014)

My 1.4x II have been behaving similarly for couple of year now - I have to manually push the switch in every time before it locks. Once it "clicks" the connection is very secure. I rarely operate in the humid environment, but work in the sub-zero conditions quite often..


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## mackguyver (Jan 14, 2014)

ichetov said:


> My 1.4x II have been behaving similarly for couple of year now - I have to manually push the switch in every time before it locks. Once it "clicks" the connection is very secure. I rarely operate in the humid environment, but work in the sub-zero conditions quite often..


I can certainly see the cold affecting things and have had the issue of having to manually push the pin all the way closed before, but most of the time, it won't lock no matter how much I fool with the switch. I have lubricate the pin to get it to lock again.


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## privatebydesign (Jan 14, 2014)

I have had that happen with my 2X TC MkII often. My 300 f2.8 has fallen off my body twice, well the other way around really the body falls off the lens, because of it.

I just make sure there is a very positive lock now.

My 12mm Canon extension tube is funny too, it rotates all the way round when unmounting, when you go to take it off the lens you can twist it either way.


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## tron (Jan 14, 2014)

I had never a problem with my 1.4X II and 2X II converters. But I have ordered 2X III (I will part exchange it with my 2X II in a couple of weeks though so I guess I will have to check for this...)


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## fugu (Jan 14, 2014)

My father-in-law gave me an old 1.4x v1 that had this issue after he upgraded to one of the newer versions. He had to manually push the switch forward to lock in the lens every time he attached it. I slightly loosened the screws on the metal flange that the lens locks into (I didn't take the plate off), and the spring pin freed up. I tightened them back down, and it works perfectly again.


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## Mt Spokane Photography (Jan 14, 2014)

I've had several MKI's, MK II's as well as a MK III and not noticed a issue. I always check a lens or adapter to make sure its locked, My hearing is poor and I can't hear a click, but a quick twist verifies its locked. I have very infrequently found a lens that did not lock, but tightening it caused it to slip into place, so I've always written that off as my carelessness.


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## swampler (Jun 15, 2018)

I know this is an old thread, but did anyone ever find a solution for this? My 2x v III is sticking and I have to wiggle/push the release button to make it lock securely. I'm just lucky I found it was loose before dropping my lens or body.


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## Mt Spokane Photography (Jun 17, 2018)

There is a pin on the extender that drops into a hole in the lens. The pin or mechanism for it can become bent. The same thing happens to the camera bodies occasionally. It may be difficult to see the issue, but get it fixed rather than a much more expensive cost to repair a dropped lens.


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