Petroleum Jelly and o-rings!

Alright! I have read a lot of threads around here! And I have seen where people are horribly against using petroleum jelly on o-rings! However; I am now questioning wheather or not these opinions are scientifically based or if they are simply opinions. I have looked at this chart from marco (http://www.marcorubber.com/material_chart.htm) and others like it.

If I am not mistaken, surefire and other companies use Buna-N aka NBR aka Nitrile o-rings. According to the charts I have been reading, Nitrile is extremely petroleum resistant. Wouldn't this mean things like vaseline would be great lubricants? Now if the o-rings are silicone, then by no means should petroleum jelly be used!
All thoughts are apprecaited, but scientific reasons are prefered!

This is about as "non-scientific" as you can get, but since pure
silicone grease is only $2.00 for a little tube, that will last years,
that's what I use.

This is what the manufacturers tell me to use, so, that's good
enough for me.

Now, if they where recommending I use something that costs alot
of money, I would need a good explanation.

If you know what the o-rings are made of, it shouldn't be that hard to find out what will harm them and what won't. My problem is, it's rarely specified what they're made of. Silicone grease apparantly shouldn't be used on silicone o-rings as it causes them to swell. From experience, petrolium jelly seems to have a bad effect on some o-rings but I don't know what they were made of. Another problem with petrolium jelly is it gets displaced easily, whereas silicone grease stays put, and almost seems to repel water making it good for water resistance if that's a concern.

Incidentally, Surefire recommend silicone grease for their o-rings, and tell you NOT to use petrolium based lubricants.

All our modern flashaholic lights use modern materials for their o-rings which have no problem with petroleum products. The problem with Vaseline is that it's not designed for heat - it will melt at higher temperatures, making a mess on your flashlight/hands and leaving your light vulnerable.

If you're interested in getting a flashlight-specific lube, the three most popular choices are Nyogel 760 (http://www.lighthound.com/NyoGel-760..._p_6-1343.html), Nanolube StClaire (http://www.nanolube.com/), and Sandwich Shoppe Krytox 50/50 (http://theledguy.chainreactionweb.co...roducts_id=710).

I think most lube and o-ring preference is based on personal opinion or else particular circumstances unique to a light - user combination. Use whatever is easiest/cheapest for you to get and works the best. If there's a problem o-rings are cheap and most manufactures will send you new ones if you ask them.

I use some silicone grease I got a Lowe's on my Eagletac. Works fine, but I know of at least one person who had problems with using a silicone based product on their Eagletac. It just goes to show, you can't be sure what will or won't work.

http://www.cpfmarketplace.com/mp/showthread.php?t=189424

Saint_Dogbert said:

but I know of at least one person who had problems with using a silicone based product on their Eagletac. It just goes to show, you can't be sure what will or won't work.

Click to expand...

IIRC Eagletac use silicone o-rings. That may have been the problem. I've read that they absorb the silicone causing them to swell which can spoil the fit.

PsychoBunny said:

This is about as "non-scientific" as you can get, but since pure
silicone grease is only $2.00 for a little tube, that will last years,
that's what I use.

Click to expand...

Mr. Bunny (my mom always said it was rude to refer to people you just met as either psycho or by their first name so that would really be a double whammy) could you share a link for the $2 grease? Everyone else's is about $10 or more. Thanks!