Greasing O-rings

[vicky]

For example, in Ikelite housings only some of the o-rings need "greasing". Usually o-rings that need a slight greasing are those who seal "moving parts" or "screwing/rotating parts" like torch-heads, housing ports, cable connectors, etc.

O-rings (the ones that need greasing) should be greased only slightly. Too much grease will only resulty in too much dirt and sand sticking to it, increasing o-ring failure risks --> leakage.
IMHO handling too much with o-rings, removing them frequently for cleaning, over greasing them etc- result only in one thing- increasing risks of water leakage. When I go diving I only clean the o-rings after I get back home. I replace film, batteries, lenses etc. on a clean place and close it again. No o-ring removal and no greasing. I'll remove and clean the o-ring only after I get back home usually after 2-5 days of diving.

Remeber it is the o-ring who does the sealing, *not* the grease. Grease is used only to make a better fitting of the o-ring.

Don't forget to make sure that you are using the appropiate grease for your o-rings. Some can be damaged with the wrong grease (for example they can get swelled, over-extended, etc).
Not sure? go RTFM or ask the manufacturer what type of grease is the right one.

 

[amandasdaddy]

Vicky,
You bring up some good points. I operated the same way. Dive first, inspect and clean o-rings after...maybe. That is until I flooded my camera.
Then when I rented my camera in CZM, I saw how professionals work. They clean and grease before each dive. She cleaned everything off with windex and then used the mfg's suggested grease and lightly lubed each and every o-ring.

She has never had a camera flood that she had prep'd. She rents cameras every day... I think I learned a lot from her.

My advice - follow the pro's example. Clean and grease before you risk flooding your own camera.

That's what I am gonna do. Vicky - If you haven't flooded a camera housing yet, you will if you continue.

Good luck. Just my 2 cents.

 

[clootie]

I have a Nikonos V, so if I don't finish a roll of film in one dive, I'm not going to open it between dives, just when I change films. And for the lens, every time I change it, or once a day, depending on which is more frequent. I've known photo pros who also felt you (or perhaps their clients at least) could cause flooding by taking out a clean o-ring and greasing it, and they hadn't flooded any cameras either - though 2-5 days would feel too long for me personally. As Dee says, depends partly on the diving you are doing.

Exception - last dive of trip, if I have less than a full roll used, then yes, I will rewind it part used & open the camera. I also take of the lens, and remove all the o rings and store the camera apart and all clean. So I know when I go on the next dive trip I need to put them all back on freshly cleaned & greased, one by one, so as not to inadvertently miss just one...

Dee - I have seen one Japanese video camera housing (cute thing, clear PVC, light, small), which had a permanent o-ring (a c-ring? I think they said) sealed onto the body. The door shut onto that. You needed to return it to the maker for servicing every so often when they would replace this seal - but you didn't grease it. I was looking on behalf of a friend, but I sent them an e-mail saying I wouldn't buy this for me, so didn't feel good about getting it for them (sending it back to Japan would also have been more trouble for them than me at the time). They shopped elsewhere.

 

[Hallmac]

jwlast once bubbled...
Anybody use this technique? If so or if not, how often should the o-rings be greased? Should the rings be greased periodically with the rings still in the camera? If so, when is considered "adequately greased?"

Thanks...

JT

Never grease while in the housing. Adequately greased means=
the o-ring shines but grease is not visible.

Hallmac

 

[Albion]

Fortunately I have a gates housing which uses a dry o ring o nthe main joint so makes my life easier, no messy o rings to play with, however this is why you are greasing up.

Most O rings are actually designed to seal dry. An o ring is meant to deform in the o ring groove in order to provide a seal.

Some times when you turn on your air there is a twok noise, this is the o ring leaping across the groove to deform itself. If you turn on your air and there is a leak, sometimes turning it off, purging, then opening the tank valve very quickly can get a seal, the sudden in rush forces the o ring to move. Basically the o ring is old hard and not moving around in the groove very well, maybe its time to change the o ring.

O rings are a very versatile sealing device however they are really a high pressure seal.

Anyway back to cameras, your camera housing is only going to a depth of maybe 40m max and at a slow rate, so the o ring has only a small 4 bar differential pressure acrooss it and so it is not so keen to slide. This is where the grease comes in to help it to slide. So as has been said earleir dont pile it on, the excess grease will just stop the o ring working. If there is a big glob between the o ring and the wall of the groove, when the pressure comes on the o ring will be in an 's' shape and not flattening itself against the wall. Same applies to spreading greesae on whilst o irng is already in place, tyou are not going to get ti between the oring and the back of the groove so it has nol ubrication to help it to slide.

Hope that helps to understand what is going on.

I used to work for a company that made seals for rotating shafts sometimes sealing LNG at 200Bar, hence o ring fitting and ensuring cleanliness was not to be fooled with.

 

[RSdiver]

Dee bubbled...

Use very little grease, just enough to make the o-ring shiny and slick.

This is true for the black O-Rings that are made of Butyl rubber, which is 99%, but my Nikonos RS uses Viton O-Rings for the back+lens which are silicon and shed the grease. In the annual servicing pamphlet that Nikon USA sends with all RS's that complete annual servicing, they recommend using 2-3 times as much grease as compared to the black butyl (Nik V) O-Rings.

I clean the O-Rings EVERY time I change film/lens and even rotate the O-Ring 180 degress.

Yeah, it quite probably sounds retentive, but definitely is not overkill. Ask any dive shop that sells photo equipment, they usually keep a flooded camera around to demonstrate the catastrophy that could happen.

I'll bet the diver that flooded the camera felt they had performed sufficient maintenance prior to the flood.

 

[sundtzu]

It also depends on the manufacturers instructions...I've got a Reefmaster RC and the manual says not to remove or grease the o-ring, just clean it completely in place(its glued in anyway).