Need help.. What is the best way to separate two extension rings?

Hi, I came back from a dive. I have two extension rings that refuse to turn in order to separate them.

Any tips ?

If they always go together - Can I just keep them together ? 

Thanks

Ido

Maybe two strap wrenches?

I would be wary about keeping them together forever - for one thing, you may want to separate them at some point; for another, the o-ring seal may deteriorate over the years and you could get a leak at the most inopportune moment.

unfortunately strap wrenches did do it well.. I tried

Are they made of metal? May be soak them a bit in warm water to make the metal expand before trying to separate them?

Yep. They are metal. I put them in warm water.. and - still they are stuck 

Put them in a freezer for a while then pour hot water over one - the one that on the outside at the joint. Never had to try it, brute force and ignorance usually does the job when mine get stuck.

Check if the extension ring lock is locked or not

Sometime it's not unlocked all the way (happened to me a lot at the first times with my fantasea extensions)

Are you trying to separate them after they have dried out?  maybe soak them a few days in water, also be sure you are turning in the right direction!   Try turning both ways.  Assuming you manage to separate them a little more lube on the o-ring is worth considering for o-ring joints where rotation is required - just a little more, don't drown it.

Thanks. I will try it. 

After much praying, crying, and bagging, this tool did the work:

Looks scary. Great that it worked though. I can well understand the progression from praying to crying - sweating too .....

I see you’ve done it successfully but I’ve dealt with it previously by mounting the ports on the housing, and rotating them against each other.

On 1/8/2023 at 11:21 AM, ido said:

unfortunately strap wrenches did do it well.. I tried

 

Bigger strap wrenches. ;-)

It sounds like they're more than "stuck".  Perhaps corroded together. But I'm not kidding about bigger strap wrenches. If they're gripping but you just can't move them, try a piece of pipe over the handle with the other ring in a well-padded vice.

Alternately (and this might sound dumb, but I've done it!)... Assuming it is salt-water corrosion, try soaking them in a bowl of warm salt water. If you remember high-school chemistry, "like dissolves like". So use salt to dissolve salt corrosion.

Years ago, I lent a friend a Nikonos V. He gave it back after a few weeks, assuring me that he'd soaked in fresh water every night. When I went to use a few MONTHS later, the strobe port plug was "one with the body".

At the time, I had a large salt water aquarium, so I tossed it in there for (I think a week, or maybe two), took it out, soaked it in fresh, tried it and easily unscrewed the port. I still have that camera.

As for just leaving them together, that would work in the short term, but before long the o-ring will dry out and likely start to leak. By then, you'll never get the rings apart.

Oh I see you were successful... Congrats. You might still soak the rings to clean them properly.

3 hours ago, Stoo said:

Bigger strap wrenches. ;-)

It sounds like they're more than "stuck".  Perhaps corroded together. But I'm not kidding about bigger strap wrenches. If they're gripping but you just can't move them, try a piece of pipe over the handle with the other ring in a well-padded vice.

Thank you very much.  very useful tips. 

4 hours ago, Stoo said:

Alternately (and this might sound dumb, but I've done it!)... Assuming it is salt-water corrosion, try soaking them in a bowl of warm salt water. If you remember high-school chemistry, "like dissolves like". So use salt to dissolve salt corrosion.

Super tip, Stoo. I knew I should have paid more attention at chemistry

I think it was the only thing I retained... ;-)

On 1/18/2023 at 8:05 PM, TimG said:

Alternately (and this might sound dumb, but I've done it!)... Assuming it is salt-water corrosion, try soaking them in a bowl of warm salt water. If you remember high-school chemistry, "like dissolves like". So use salt to dissolve salt corrosion.

Super tip, Stoo. I knew I should have paid more attention at chemistry

Unfortunately that is not what is happening.  The correct principle is Le Chatelier's principle.  If the concentration of salt in the water is lower the ions will tend to move towards the area of lower concentration.  What is correct is using warm water, salt is more soluble in warm water.  The corrosion products are also soluble in case of aluminium chloride.

What you do need to do is soak for a long time, the driving force to move the salt out of the small gaps is quite small.  Salt water hangs around in those small gaps for a long time.  My INON strobes are soaked for an hour after a day's diving and the gap below the o-ring remains full of water and even after an hour it is still salty.  If I leave them till the next day to change batteries salt crystals form.  The lesson here is this is why you need to break down your equipment - any salt water left behind slowly evaporates and becomes extremely corrosive.

Not to be too pedantic but it isn't Le Chatelier either. It is more like Fick's law, diffusion proceeds from areas of higher concentration to lower concentration. Warm water helps as Chris points out, stirring is best but in the case of a sealed system it is hard to get the solution inside to move very much. Putting the parts in an ultrasonic cleaner often helps too.

Bill

On 2/4/2023 at 6:51 PM, bvanant said:

Not to be too pedantic but it isn't Le Chatelier either. It is more like Fick's law...

 

I knew that! That's why whenever corrosion gets the better of me, I usually moan, "What the Fick..."