Slight "play" on Tamron zoom

[fatigue]

If you noticed your lens got this slight "play" (slack) when you zoom, stop using and send immediately for repair. It's just a loose screw. If you continue to use, it might end up like this:

Encoder damaged by zoom brush

 

[fatigue]

The arrow shows the loose screw while the encircled part shows the damage

 

[Octarine]

Too late ... my zoom mechanism is broken. Usually bit of 'play' in mechanical parts is normal .. but this seems to be a serious issue here.
Would you be able to help?

 

[nightwolf75]

very useful info. sticky it for everyone's reference. kindly refrain from posting unnecessary comments unless you have something specific to add to fatigue's info. thanks!

 

[begintoend]

Sorry as this term is noob to me... but can some bro explain about what's "slack" or "play" on zoom? How will a user experience it?

Given a rough guess, I am assuming that the "amount to turn" to achieve a zoom is too much.. meaning 17mm to 55mm achieved in half turn.
eg:
Therefore 17mm to say... 30mm needs only a quarter turn on a good lens.
If it has slack, you will use more than a quarter turn to achieve that 30mm.


Am I right??? Am really keen to understand this. I think is useful info.

 

[fatigue]

Sorry for the term used. I couldn't think of the best word to describe it.
It's when you're turning the zoom ring but the glass assembly does not move at all.
If it's more than 3mm play, It could be too late.
If you hear something like a grinding a grinding of sand, your actually ripping the encoder.

Will post the procedure how to tighten if I happen to open the same lens again

 

[elladan]

it happened to my 17-50 and my friend's 17-50 as well... seems to be a design flaw of the lens.

 

[fatigue]

Someone volunteered to use his lens for documentation, just waiting for his free time
Anybody who is interested on how to fix this lens can also join us, just send me a PM

 

[fatigue]

As promised, here's how to tighten the zoom mechanism.
The following pictures may not be good, i just took them in a hurry. :embrass:

I got these lenses today, all with the same problem

 

[fatigue]

Remove the screws

Lift the mount and push the black rear cover from the inside.
(There's a plastic catch, push from the catch to prevent damaging the black plastic cover)

 

[fatigue]

Remove the 2 screws indicated by the pink arrow and unlock the FFC cable connectors indicated by red arrows

Then remove the circuit board

 

[fatigue]

Remove the screws (take note that the screws indicated by green and red arrows are of different length than screws indicated by the blue arrows)

 

[fatigue]

Gently remove the top part.
Now you can see the mechanism that maintains the constant aperture.
As you zoom in and out, the slanted slit adjust the aperture mechanism automatically.

 

[fatigue]

Here's the part you need to tighten. Add a drop of thread lock inside the screw.

 

[fatigue]

Reassemble everything in reverse order


During reassembly, switch down the blue switch

Remove the switch, there's 4 plastic catch

 

[fatigue]

Push the switch in place.
(remember to set the switch to AF to engage the levers correctly)

 

[fatigue]

After the spacer, return the metal mount then tighten the screw

Fix the connector in place
Then snap the black rear cover.

Note: the plastic thread is easily damaged.
Putting the screws in place, make sure to turn the screws counterclockwise until you hear the click sound. Then tighten gently

 

[theveed]

You make it look so easy bud hehe.

 

[adrianseetho]

you are awesome!

Thanks once again!

 

[Octarine]

My lens is back to life after it was down for some months. David has gifted hands!
Thanks so much for your help!