Subal extension tube

Hi y'all,

I recently acquired a used Subal C10 rig that included among other things an extension tube. If I had to guess, I'd say it's 4" long. This past weekend I put the rig together with a 10d, 50m macro lens, and a 1:1 diopter ("Life Size Converter" in Canonese). The only way this lens combination fits is with the extension tube attached to a macro port.

I lubed up the O-ring between the port and the extension tube as I normally would a camera O-ring, which is a very thin coating of grease.

Well, the diving got blown out over the weekend and I didn't get to shoot. When I went to disassemble the rig last night, I had a very hard time getting the port and the extension tube apart. I did eventually get them apart, and didn't have to resort to anything outside of elbow grease, but I was wondering if I was missing something.

Is it standard practice to lube up the O-ring between the flat port and extension tube more than normal?

Is it just something where I need to stop being a sissy?

I hate to use a lot of strength to do anything on the housing, because I don't want to break anything.

Grease is to keep the o-ring from drying out, and minimal amount is used. It does not serve to lubricate in a frictional context. Nothing comes to mind about why in might be overly tight. Mine are not that hard to take apart. This stuff is pretty robust. Difficult to imagine you could break something by simply twisting with your hands. Perhaps there is some residual build-up on o-flange parts. Is it that difficult to assemble as well?

Perhaps silly to ask, but just to be sure, do you open the housing first? Do you then remove port and extension, or just port?

Hi Kilili,

I did a pretty thorough inspection/cleaning with a magnifying glass and super bright light before assembling it for the first time. I don't think there's any residue anywhere in the extension tube. It went together easily, which is why I was surprised it was difficult to get apart.

I did open the housing first, and took the extension tube & port off the housing before I took those two entities apart.

For whatever it's worth, the port's O-ring is the small diameter kind and the extension tube's O-ring is the big diameter kind. So I would expect the port to be easier to get out of the extension tube than harder...

Thanks for the input!

-b

I have found that the extension tubes go together easily but require strap wrenches to twist them apart.

Elmer

Is the lube you used compliant with the ''O' ring? Some grease will cause certain rings to swell.

If I disassemble my Subal ports/extensions with in several days, they come apart easily. If left together for two weeks, then I need another guy's help or a wrench.

Putting extra grease on is not recommended as it will accumulate dirt leasing to leaks.

This is highly undesireable !!!

Not sure you can mix type 3 and type 4 components!

I have found that the extension tubes go together easily but require strap wrenches to twist them apart.

Ditto on the strap wrench. I have had difficulty at times and have found that a strap wrench comes in very handy. I actually went out and bought one online and now it goes with me whenever I go on a dive trip.

Ellen

Thanks for the opinions all! A strap wrench looks like it's in my future... any suggestions on good ones for this application?

> > Not sure you can mix type 3 and type 4 components!

So is this a reference to revisions of the extension tube and flat port? I'm a Subal n00b (been diving a Light & Motion rig for about 10 years) - so I'm pretty green at identifying what is what on my new-to-me C10 rig.

Thanks again everyone, much appreciated!

-b

I bought two strap wrenches at sears. Look at: http://www.sears.com/shc/s/p_10153_12605_0...mp;blockType=G5

You want the plastic handle with a rubber strap. The rubber strap does not scratch your extension.

Awesome, I'll get those from Sears. I really appreciate it!

Cheers,

b