Titanium thread grease.

[fyrstormer]

Re. this thread: https://www.candlepowerforums.com/threads/234356 (probably would've been better to add onto it, but it's too late to delete this now...)

Just thought I'd let you guys know that I've spoken with a tribologist on a car forum I'm a member of, and she's confirmed that sodium bicarbonate mixed with a binding agent is a suitable lubricant for titanium screw threads (i.e. there won't be any harmful chemical reactions over time). Because my favorite thread lube is lithium grease, I mixed a thimble-full of baking soda with a 35mm-film-canister-full of lithium grease, and applied it to my Raw Ti and my LunaSol, and sure enough it provides the best feel of anything I've tried so far. There's a slight gritty sensation that subsides after a couple of days, but the thread stiction is virtually nonexistent now. Definitely worth the time to mix up a batch and give it a shot, just make sure you wash the threads thoroughly first.

 

[brighterisbetter]

This sounds interesting. Is there any particular lithium grease you'd suggest? I'm fond of Lubriplate No.105 and already have some, but if you've got a different one that we should try please let us know.

 

[fyrstormer]

I use a yellowish translucent lithium grease designed for wheel bearings; I think it has MoS2 in it. White lithium grease should work fine too, though.

I've since tried the same approach using heavy machine oil instead of grease, and I still like the grease better. As a carrier for the sodium bicarbonate, it holds in-place better than oil does, and there's no way it could drip in between the battery tube and PD piston, thereby avoiding making that feel gritty in operation.

As the threads have ground up the stuff some more, it's gotten progressively smoother. I'm quite impressed with this solution.

 

[fyrstormer]

I just put 2+2 together on why the sodium bicarbonate works so well as an additive in lithium grease -- sodium and lithium are both alkali metals, and presumably they are both present in the grease as alkaline compounds, and generally anything that is slippery is alkaline. So basically by adding the baking soda to the grease, you're turning it from lithium grease into lithium and sodium grease mixed together, and I know both are valid lubricants because I've seen them both for sale in auto parts stores.

When you add sodium bicarbonate to machine oil, you're probably just manufacturing a crude form of sodium grease. The other alternative suggested, cigar ashes, I'm not sure how that works.

Some light reading: http://www.reliabilityweb.com/art04/understanding_grease.htm

 

[socom1970]

I thought Krytox was best to use on titanium lights. That's what I use currently for mine. I don't know if I would use something else that I could just mix together, unless other TI users could confirm it. As well, I would want an exact "recipie" involving amounts of specific ingredients as well as preparation of the mixture if I would even consider using it on a $450+ TI light.

 

[fyrstormer]

Suit yourself, but my tribologist friend knows her stuff (she works for the company that makes Loc-Tite) and my fingers tell me the threads are not grinding anymore. The grease is also not turning black nearly as fast as it used to.

 

[McGizmo]

I plan to try some baking soda in the Krytox 50/50 blend when I get around to it. :thinking: :shrug:

 

[nfetterly]

Krytox 50/50 blend available at link below.

I'll send some baking soda FREE along with it at your request

 

[fyrstormer]

Don, is Krytox what you use on all of your new lights?

 

[McGizmo]

Don, is Krytox what you use on all of your new lights?

Yes

 

[RocketTomato]

I have three Ti-PD Ss from the last two waves, and a Lunasol 20 and none of the 4 have gritty, tight or sticky threads. (Though I know this was a problem with earlier versions.) I use the Krytox 50/50 blend and sometimes just Krytox grease and they both work well. I also use Krytox on the pistons.

I have tried the precision oiler with teflon from radioshack and that actually worked too well, and I found that the heads would unscrew too easily.

The only gritty threads that I have personally encountered where on a Novatac 120P. I cleaned the threads well (i.e. a q-tip soaked in isoproypl alcohol), relubed them and the o-rings and the grittyness went away.

In regards to using lithium grease with sodium bicarbonate, it sounds like you are making a colloidal suspension. What I think is happening, is that you are basically thickening the grease which helps it stay in place better. Same thing is probably occurring with the cigar ash. And yes, you are probably getting some ion exchange and making a little bit of sodium grease and therefore lithium bicarbonate.

 

[fyrstormer]

I agree that it's a colloidal suspension, at least once the sodium bicarbonate has a chance to fully dissolve into the base oil -- but then again, grease is already a colloidal suspension of metal soap in oil anyway, so aside from mixing two kinds of soaps together, it all comes out in the wash.

(pun intended. )

 

[lyte~speede]

Quick comment...I'd be certain about the compound formula BEFORE mixing sodium bicarb. into non-generic/brand lubricants such as krytox. It's "additives" you need to be aware of.

WHATEVER mix you create with the intension of trying baking soda use SCANT amounts of soda--you can add as you go.

 

[lyte~speede]

<---fyrstormer...

I agree with the "suit yourself" posture. If one returns to my original thread introducing soda and ash additions, they would see that one of my consults was with a materials test guy. I won't get into the science of our original discussion; supporting statements can be found in this thread. I was trying to avoid applying brand-x/superlube "unknowns" to MY multi-hundred dollar lights.

 

[RocketTomato]

lyte-speede, from what I gather, you are basically making your own sodium grease by adding the baking soda to the miltec-1, correct?

What do the materials test guy and the tribologist think of PTFE (Teflon) based lubes?

(We should get the two threads merged)

 

[fyrstormer]

Quick comment...I'd be certain about the compound formula BEFORE mixing sodium bicarb. into non-generic/brand lubricants such as krytox. It's "additives" you need to be aware of.

WHATEVER mix you create with the intension of trying baking soda use SCANT amounts of soda--you can add as you go.

I used about a 15:1 ratio. I think I could go higher, but it would take longer for the threads to grind up all the baking soda.

Interestingly (but not surprisingly), the un-broken-in threads on my new PD-S chewed through the baking soda in no time compared to the threads on my LunaSol, which I have been steadily polishing with un-modified lithium grease for about a month now.

 

[fyrstormer]

lyte-speede, from what I gather, you are basically making your own sodium grease by adding the baking soda to the miltec-1, correct?

What do the materials test guy and the tribologist think of PTFE (Teflon) based lubes?

(We should get the two threads merged)

The tribologist said a Teflon film would work (as noted by whoever it was who said they used a wrap of Teflon tape), but the trick is bonding it to the metal effectively. That's kind of an industrial-strength process, hence why there are no do-it-yourself Teflon pan lining kits.

It seems that the issue with titanium in general is that it's very cohesive, and when given the option it would much rather stick to itself than stick to grease or anything else -- which is why if you look closely at the black stuff on titanium threads, it's actually darkened by shreds of titanium large enough to be seen with the naked eye. It tears off bits of itself because it likes to stick to itself so much, whereas most metals will self-polish when rubbed against each other.

I'd like to try aluminum grease if I can ever find any, because according to the article I linked to, it is extraordinarily sticky compared to most greases, and it should maintain a film much more effectively.

 

[karlthev]

I've used teflon tape on my PDs and do now on a Ti Wee. I agree it doesn't bond to the threads but then again, I don't think (just an opinion here folks!) there is much mechanical force within the thread to thread contact to need a bonding per se. As I said, OPINION on my part, not any scientific knowledge. All I can say that despite the periodic need to replace it, the tape method works fine for my purpose. Now I EDC the Ti Wee but not the PDs at this point. I might find there to be a need for much more frequent replacement of the tape and associated time consumption in doing so if I did EDC the PDs and used them (and the tape) more extensively. Maybe then I'd be less enthusiastic about its use...maybe not....:thinking:



Karl

 

[fyrstormer]

I mixed up a new batch of grease with a 5:1 ratio of grease to baking soda, and I used a rotary-planer bit for my Dremel to assist with the mixing process. (It worked brilliantly, FYI.) I like the new mixture much better than the older 15:1 mixture. Obviously it's thicker, but interestingly, it's not as much thicker as I would've expected with 3x the solid mass being added. Really, it's just more gelatinous now.

I applied it to the various titanium items I have (PD-S, LunaSol, Raw Ti, and tiny pen from J.S. Burly's), and it works splendidly. No grittiness at all, which suggests that any grittiness I felt before was due to insufficient mixing of the baking soda, not merely the presence of the baking soda at all.

What I'm aiming for, FYI, is to get rid of anything that resembles a sensation of metal-on-metal contact. I know I won't actually eliminate it, but I want it to be so little I don't notice, much like the way greased aluminum threads feel. (actually, that is a pretty good indication that aluminum grease would be a good thing to try.) I know you're all hanging on my every word, so I'll keep you apprised as soon as I come up with anything.

 

[fyrstormer]

Well, I got some aluminum grease, and I have a couple of thoughts about it. One, it's much thinner than I expected, almost the consistency of Cool Whip, and two, despite being so thin it does indeed stick to the titanium better than anything else I've tried. However, while it seems to maintain a film quite nicely, it doesn't do much to capture the little metal bits that get shaved off the threads, and as such they roll around in the threads and feel gritty. A thicker version of this grease would be nice -- which is what I ordered, but they sent me the thinner one instead. I've ordered some Teflon powder from a piano-supply shop in Cali, and I'm going to mix some of that in with the aluminum grease to see how it behaves. I'm hoping it's the silver bullet I've been looking for.