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Tribolube 71 for loop and DSV?

Discussion in 'Rebreather Diving' started by taimen, Dec 3, 2019.

  1. taimen

    taimen ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: 200 - 499
    Location: Europe
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    Is Tribolube 71 significantly better than silicone grease for DSV and loop o-ring lubrication?
    I have DSV annual maintenance approaching and wonder is it worth ordering some now.
     
  2. Jeremy Williams

    Jeremy Williams Nassau Grouper

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    it seems to me that just the opposite is true. The typical silicone lubricants are much better at being a lubricant than Tribo. They are just not oxygen compatible. I’m still using only Tribo on my loop but that is more from a desire to avoid contamination than because it’s actually “better”. It’s really tempting to use something else in a couple of places because Tribo is such a poor general purpose lubricant.
     
    taimen likes this.
  3. muzikbiz22

    muzikbiz22 Manta Ray

    # of Dives: I just don't log dives
    Location: Southern California
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    I use Tribo-71 on darn near everything; BOV, loop hoses, counterlung o-rings, pretty much all o-rings, plus DSLR housing, dive lights, Shearwarer, etc.
     
    taimen likes this.
  4. tbone1004

    tbone1004 ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: I'm a Fish!
    Location: Greenville, South Carolina, United States
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    I'm with @Jeremy Williams , the normal silicone is a far better lubricant. The system isn't under pressurized O2 so there is no need to worry about O2 compatible lubricants. The only potential one is around the solenoid if you have one, but you shouldn't be using lube around there anyway. Everything on the loop is better off with dow111
     
    Danseur and taimen like this.
  5. nickbutcher

    nickbutcher Angel Fish

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    This ^^^, in spades.

    I only use 'O2 grease' on high pressure components. Everything else is lubricated with silicone grease.
     
    taimen and tbone1004 like this.
  6. Geo7

    Geo7 Angel Fish

    # of Dives: 2,500 - 4,999
    Location: Los Angeles
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    My understanding from the reg discussions on SB and talking to reg technicians is:

    Silicone (Dow Corning 111, or Molykote) is more hydrophobic and sticky. As pointed out above, not O2-proof, and the contamination argument is a good one, so I largely avoid silicone at the moment (but for Subcon wetconnectors it is necessary).

    Krytox GPL-205 has similar hydrophobic properties (but nothing comes close to silicone) for applications where you want something sticky to prevent corrosion (it is O2-proof). I am using this on my SPG swivels as the Tribolube might get washed out quicker.

    Tribolube 71 and Christolube MCG111 are supposed to be better lubricants for dynamic o-rings such as pistons (better lubricant as in they allow the piston to move and react quicker and improve performance).

    Tribolube 66 and Christolube MCG129 are a bit thicker and used for static o-ring applications.

    So for a DSV barrel I guess I'd choose a more sticky lubricant if it does not seal well, or Tribolube 71 if it does not move easily enough. At least that's my understanding, others may chime in, who have compared all of these more extensively.
     
  7. taimen

    taimen ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: 200 - 499
    Location: Europe
    747
    362
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    Thanks! Silicone grease it is. I have used silicone grease everywhere, except high pressure O2 parts. I knew there are people who use Tribolube 71 as universal lubricant and was curious.
     
  8. davehicks

    davehicks Barracuda

    # of Dives: 1,000 - 2,499
    Location: Seattle
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    I use Silicone grease on all of the external low pressure o-rings on my rebreathers and have for over a dozen years with no issues. It works great, and you typically need to use a pretty large amount given the number of fittings and their fairly large surface area. I also found that you get a lot of "build up" from the tribolube on these fittings. That makes a mess and requires more clean up and removal of the material. Silicone does not do this.

    However I use Tribolube 71 almost everywhere else. Cameras, strobes, regulators, lights, etc. The tribolube has better compatibility with the wide variety of oring materials in all these other devices, and you typically only use tiny amounts in these applications.
     
  9. Fibonacci

    Fibonacci Manta Ray

    # of Dives: 500 - 999
    Location: Melbourne, Australia
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    I used to use a mix of Dow Corning 111 for static o-rings and Tribolube 71 for anything dynamic (piston o-rings, AL balance chamber shaft, Atomic seat saver and swivel etc).
    I've found the more 'slippery' Tribolube works well in these specific areas, but like @davehicks I find Tribolube or Christolube has a tendency to migrate in the air stream and leave a thin coating all over the place unless you use the smallest possible amount.

    Lately I discovered Silicone Lubricating Grease with Syncolon® (PTFE) from The O-Ring Store which I'm tending to use more.
    It is much less viscous than Dow 111 and really good to put a minimal amount to just shine the o-ring, stays put in sea water too!
    Super Lube® 92003 Silicone Lubricating Grease 3 oz. Tube [92003] : The O-Ring Store LLC, We make getting O-Rings easy!
     
    taimen likes this.
  10. Geo7

    Geo7 Angel Fish

    # of Dives: 2,500 - 4,999
    Location: Los Angeles
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    This might be another important point wherever silicone o-rings are used (which does not seem to be the case in regulators, but I think some CCRs use them in the loop). I think silicon parts can swell or deform if silicon grease is applied to them? If for example the DSV flapper valves were made of silicone and got in contact with grease, could that be a problem? It seems Tribolube avoids several problems, but I'd check with the manufacturer to be sure. FWIW, the (unofficial) Megalodon DSV rebuild instructions I have found online specify Christolube.
     

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