Lubricating Silicone O rings???

[steveuk]

Hi guys, I have a question about Silicone O rings... What do you lubricate them with

I ask this because it seems mine are very tight in the wtc tube.
Before, I have had problems when using syringes to bail water out of my 'old school' prssure hull (- remember them, before cylinders came out ) I used machine oil to lubricate them which worked for a while but then the syringe rubber seemed to soak in the oil and expanded so it became an even tighter fit. I think this happened to an extent using Vaseline too. It seems to soak into the rubber which expanded and grew into tighter fit. Had to throw them in the end

I don't want this to happen with my wtc o rings.

Is there a special silicone oil ...What would you advise please

[Guest]

Hi Steve,

You musn't use any

Hi Steve,

You musn't use any mineral oil based products on neoprene or nitrile seals, silicone I thought was a bit more resistant to mineral based products. Personally I wouldn't use silicone for an O-ring hull seal- they're very fragile in my experience. Nitrile is best closely followed by neoprene- they're usually cheaper than silicone rings too.

Silicone grease is readily available, and is the perfect product for the job.

You can try your local plumbers merchants, they usually sell tubes of it.

Failing that, try the 'Servisol' brand. I got a tube many moons ago from Maplin electronics. They may no longer sell it, as Maplin seems to be getting more like a toy shop with every passing year.

Rapid sell it however (they're like Maplin used to be)-

http://www.rapidonline.com/productinfo. ... leno=61593

One tube will last you ages.

Silicone oil is also useful for lubricating valves etc.

Andy

[steveuk]

Wow that was Supa-fast response!!

Wow that was Supa-fast response!! Cheers Andy.

I didn't know that o rings were made from other materials, I just assumed they were all silicone. You learn something everyday.

O.K. I will try out the plumbers for silicone grease first.

Thanks.

[tmsmalley]

If you can't find plumbers'

If you can't find plumbers' silicone grease, scuba divers grease is a good substitute and available at any scuba shop. It is also a little less viscous than the plumbers' product and easier to apply, but more costly.

[Guest]

Steve,

Everything you ever wanted to

Steve,

Everything you ever wanted to know about o-rings, but were afraid to ask-

http://www.jameswalker.biz/docs/jwco/o_ ... ll_doc.pdf

Andy

[boss subfixer]

Steve,
Another great source for silicon

Steve,
Another great source for silicon grease is at your local swimming pool store where you go to buy the chemicals. I get mine from there.
Don.

[steveuk]

Steve,
Another great source for silicon

Steve,
Another great source for silicon grease is at your local swimming pool store where you go to buy the chemicals. I get mine from there.
Don.

That's usefull to know too - sounds like silicone grease survives chlorine then!?
I remember going to a sub meet which was organised in a swimming pool. Afterwards lots of guys were complaining that their piston type tanks had suffered and became stiffer in operation.

[Guest]

I'm not a chemist, but

I'm not a chemist, but I suspect that the chlorine that they put in swimming pools would come under the category 'chlorinated solvents'.

In the pdf that I linked to earlier, nitrile and neoprene are poor performers in relation to chlorinated solvents. Silicone doesn't fair much better either.

Fluoroelastomers however appear to be all round excellent for sub use.

I think these o-rings tend to be more expensive however.

[steveuk]

That's a very usefull table.

That's a very usefull table. Thanks for that.

[tsenecal]

The place that I buy

The place that I buy my nitrile (buna n) seals from talked with me at length about the abuse chlorine can cause on the q-rings i use (i mentioned my boat will go in pools a few times every summer, but spend most of its time in ponds). The gentleman informed me that o-rings are lucky to last for a season in a swimming pool filter (24 hours a day for 90 days, or 2000 hours) before needing to be replaced, which is why he doesn't recommend them for swimming pools. (who wants to replace the o-rings in their filter every year?)

The buna n seals, which will decay in chlorine, are 85 cents each. The other q-rings were of course impervious to chlorine, but they were $4.00 a pop for the same size.

Knowing I would probably not submerge my boat in chlorinated water for 2000 hours in my lifetime, I bought 3 sets of the 85 cent q-rings, and will replace them if I ever need to.

[boss subfixer]

Andy,
To back up what your

Andy,
To back up what your saying, I've used nitrile, neoprene and silicon orings on my pools filter hoses with a generous helping of silicon grease on them to hold them in place and to help keep them from rolling when I tighten up the union fittings. They hold up with no problems for our some what short swimming season here in New England but I've never been able to reuse the orings the next season. They break. Oh and I don't use chlorine (too finicky), I use baquasil.
Sorry if this seems to be off topic but it is real world experience with the subject at hand.
Don

[steveuk]

Hi guys, so far I

Hi guys, so far I have struck out on the shops I have visited. They all sell just mineral type greases. I will keep looking.

Meanwhile I found this can of lubricating oil in my shed. It is called "AQUA LUBE 250" from Metalyte Limited, and the description on the can says - Multipurpose demoisturing and lubricating spray with PTFE micro-suspension. Does not contain CFC. Synthetic base fluid. Water resistant. FDA approved base constituents.

Mind you it does also say - extremely flammable.

...What do you recon

[anonymous]

Hi Steve,

Sounds frightening http://www.subcommittee.com/forum/icon_biggrin.gif

Have

Hi Steve,

Sounds frightening

Have you tried plain old Vaseline or silicone grease (from a Dive Shop)?

Davy

[tmsmalley]

Hi Davy - Vaseline is

Hi Davy - Vaseline is petroleum based. I've found that after a season or two, it will rot and harden most O-rings. Best to stick to silicone grease.

[steveuk]

or silicone grease (from

or silicone grease (from a Dive Shop)?

Hmmm good idea ...there is a boat chandlers not too far away, I wonder if they might stock silicone grease.

btw what do divers use silicone grease for