How to remove the Mamiya adapter on a CZJ 180mm f2.8?

[Edmond Stuart]

I've recently bought a Carl Zeiss 180mm / 2.8 MC, fitted with a Mamiya adapter, see picture.
The serial number is: 10157669. I like to replace the adapter with another one, but I'm unable to turn the ring that holds the adapter, in either direction, that is, without applying brute force.
Before I proceed, I've a few (perhaps stupid) questions:
1. Can this adapter be removed anyhow?
2. If so, I suppose by unscrewing the ring that holds the adapter (see picture, red arrow)
But in which direction? I know that in most cases it is clockwise, that is, seeing from the rear (rather counter-intuitive, BTW).
3. Applies this to all adapters (including Mamiya)?
4. Since this ring is so firmly tightened, I can't loosen it manually. Are there special tools to apply brute force without damaging the lens body?
(BTW, there was a locking screw in this ring, which I've removed already)

http://forum.mflenses.com/jumploader.php

Comments invited.
Cheers,
Edmond.

edit1: I've uploaded the picture, but can't see it. Clearly something went wrong. Sorry.
edit2: I've put it here as well: http://www.data-odyssey.nl/images/CZJ180.JPG (removed by now)

[fuzzywuzzy]

Try posting the pic again, your first post can't contain images or links (antispam measure).

[Edmond Stuart]

[Gerald]

Note the photo below. The Sonnar 180mm F2.8 lens may be a different model of yours, and the adapter is a P6 to M42, but I think that the picture is good enough for understanding the procedure of separating the adapter from your lens. The Zebra ring is what connects the lens to the adapter. To release, you must turn the ring in the direction indicated by the red arrow. If for some reason the ring was forced in the opposite direction, you will need a lot of force to loose the ring. Do not worry, there's nothing to break, but use only your hands, not any metal tool.

[Edmond Stuart]

Hi Gerald,

Thanks for reply. Now, at least, I'm pretty sure to which direction I should turn the release ring, but I still failed when using only my hands.
Of course, using some metal gear is a big no no. In order to be able to apply enough power, I'm more thinking in the direction of a leather strap or so, something that doesn't scratch the lacker etc.
One more thing: What about using penetrating oil and/or applying heat to the release ring?

Cheers,
Edmond.

[Gerald]

[Edmond Stuart]

It's loose now!
Using leather gloves did the trick, which enabled me to put more force.
Many thanks for your help.

Cheers, E.

[Gerald]