Canon 400 2.8 L IS Tripod Ring

Guys,

I have been using my Canon EF 400 2.8 L IS for last eight months or so, just recently the tripod ring mount has strated getting jammed while rotating. It was taking me a lot of effort while rotating that from horizontal to vertical and back to horizontal.

Just yesterday, it jammed in its horizontal position and despite my best effort it is not rotating.

Can anybody help me out with the problem as how to rotate the lens on that tripod ring.

Regards

Loosen it all the way and try taking it off to have a look inside?
Edit: I thought it was the same as the 300 sry.

Thanks for the reply.
How to lose that up?
You mean opening up the tripod mount screws, I have not done so ever?

crazyskillz07 wrote in post #6208688
Loosen it all the way and try taking it off to have a look inside?

Even if you loosen it all the way, the collar doesnt come off. I honestly dont even know how to get it off. Thankfully, Ive never had that problem.

AdamLewis wrote in post #6208863
Even if you loosen it all the way, the collar doesnt come off. I honestly dont even know how to get it off. Thankfully, Ive never had that problem.

this is just a "shot in the dark" since I don't have that lens
to take the collar off of my 100-400 you have to rotate it so the screws on the lens (which are like knobs situated under the collar) align with the slots on the inside of the collar, then it comes off. It might be the same type of construction for this lens....

This is a common problem with the 400 it is due to cheap teflon bearings instead of steel bearings. The fix is very easy and you can do it your self. Canon charges about 600.00 to do this and you will have the same problem in about a year.
This is an article from Sportsshooter and parts needed. The only thing this article does not cover is that the screw driver needed is called a JIS CrossPoint the 2.0 and 2.5mm found at (http://www.micro-tools.com …ry.aspx?Categor​yCode=NIWA)

Article
This is a follow-up to the post at http://www.sportsshoot​er.com …ge_display.html​?tid=26905 to make it easier for those searching later. I found replacement bearings for the tripod collar of a Canon 400 f/2.8 IS. I bought bearings at http://www.bocabearing​s.com - part #SMR74. Stainless steel bearings (higher quality than the OEM Canon ones) - bore 4mm, diameter 7mm, thickness 2mm (reads as a 4x7x2 bearing). You need six of them - $7.95 each vs. $570 for a replacement assembly from Canon.

With new bearings and a little lube, my 400 rotates easier than it ever has - in fact, easier than any lens I've ever used. I can't be happier with it. Hope this helps some other shooters who ran into the same problem I did.
Pics of the process
http://www.sportsshoot​er.com …pe/400bearings/​index.html

Hope that helps

Thanks Gromeo
I seem to be facing the same problem that all the other guys are also facing.
Now, I need to decide that do I need to send this lens to Canon or try finding the things myself.

I only hope that this will help

Is the lens still under warranty? Maybe this would be covered?

maxloxton, one thing you did not say was how old your lens was. One thing you want to check is, remove the name plate on the collar if it has a window that shows the ball bearings you are good to go. I had a friend that ordered all the stuff needed in that article and when we took his 400 2.8is apart it did not have bearings in it, the collar just slid onto plastic area. all we did was clean inside the collar and the plastic part and add a little dry teflon lube and it was like new.

Thanks Gromeo.
The lens has been bought in Late 2006, around Nov.
Hence I am not sure whether it is the old model or the new one.
I think I need to open up the name plate on the collar to check.