How to extract an oring

[dvleemin]

Hi,
I need some sort of a tool to extract an oring without damaging it. In this case, its for an Olympus PT-010 housing, but I suspect this problem applies to a lot of things.

What's the best thing to use?

Thanks,

Darryl

 

[Stone]

. . . since I don't know what the o-ring and groove look like, but a credit card won't usually damage an o-ring. A really flimsy card (like the DAN member card) can be used, too.

 

[dvleemin]

Originally posted by Stone
. . . since I don't know what the o-ring and groove look like, but a credit card won't usually damage an o-ring. A really flimsy card (like the DAN member card) can be used, too.

Not a bad idea! I think a credit card minght be a bit thick as the grove is quite deep, but a thinner type of card might work.

You know what I would like - some of the tools dentists have, but in plastic

Darryl

 

[redacted]

I found some called the "Super Pik" that are quite soft & flexible in the drug/health supply area of Walmart.

 

[Stone]

Originally posted by awap
I found some called the "Super Pik" that are quite soft & flexible in the drug/health supply area of Walmart.

The tooth pick in a swiss army knife (especially a small one) is relatively flexible and nicely tapered.

 

[FredT]

Originally posted by dvleemin
Hi,
I need some sort of a tool to extract an oring without damaging it.
Darryl

Just WHY are you trying to save an o-ring?

Normal practice for captive rings and most dynamic and static elastomer seals is that they are never reused once disturbed or removed.

O-rings are cheap. Cameras are expensive. Carry spare rings!

In the worst case this allows the ring to be damaged during removal, thus protecting the expensive housing.

The easiest way to remove most larger O-rings is to use two thumbs and push them together along the seal line. This stretches the rubber in the seal outside the thumbs and causes the material between the thumbs to compress and "pooch" up between the thumbs. Hang a fingernail under the ring and pull up slightly while deflecting the ring away from the groove. Most rings and other seals will then roll right out of the groove once started.

FT

 

[dvleemin]

Hi Fred,
I do carry an extra oring with me. You make a good point though as to why I would ever want to remove it. I think I ready somewhere its not a good idea to store orings compressed, as they'll form an indentation, but without sealing the camera that shouldn't be a problem.

What about re-lubing the oring?

Darryl

 

[Rockhound]

I don't know anything about your setup, but I remove the user accessible O-rings from my Nikonos V and flash after every trip and replace them with "storage o-rings". In my case, these are old rings I've marked with permanent ink. This replacement includes lens rings, the loading door ring, battery compartment ring. The flash cord and extension tube rings. are not under compression, so I replace them after a thorough cleaning.

O-rings do get flat over time, but most camera rings can be removed, cleaned and lubricated without damage to the ring or seat. There are obviously o-rings and other "gaskets" that cannot be removed without damage. These need to be left alone.

The credit card trick is the best for not damaging the ring or seat in cases where simply sliding your fingers around the ring from opposite directions is insufficient.

Examine the ring carefully (under a loop, if possible) for any scratches, dents, cuts or deposits. Check and see the ring out of round. If you have any doubts, replace it.

Remember not to overlube the ring. Use a compatible lubricant and wipe away any residue. You should have as shiny ring with no globs or specks of lube on it.

Finally, double check your seats to make sure are clean.

Do this BEFORE and AFTER every trip or day of use.

 

[SubMariner]

As has already been said, you can use a credit card. It works well because the edges are rounded. And, believe it or not, Sea & Sea actually puts out s special O-Ring Card that vaguely looks like a credit card with different shapes cut out of it. It too has rounded edges. Of course like most Sea & Sea products it costs more than the plastic is worth. ut:

This is why I think the toothpick from the Swiss Army knife WILL NOT work: the edges are too sharp. The last thing you want to do is nick that o-ring!

The "two-thumbs push" that Fred described is also a very good method.

What Rockhound said about checking the O-ring is also right on. Usually the "right amount" of silicone grease to lubricate the ring is just enough to make it "shiny".

In summary, you've gotten lots of great advice.

~SubMariner~