Maybe it’s just my inability to tell good from bad but I’ve never found any differences in one lube from another when used on flashlights or guns, assuming periodic cleaning. I’ve never had an o-ring fall apart or any issues somehow related to lubrication (as far as I can tell) so I’m wondering how people decide that one is better than another?
Grease stays on rails and threads longer than oil of course but that’s seemingly about the only thing I’ve really noticed or care about.
A quart of Mobil 1 is cheap and will last forever when used on flashlights and guns
Sorry for the necro. I just happen to have WD-40 at hand. Is it harmful for the battery wrappers and protection circuits? I had to use it to remove a protected battery that got stuck in a tight tube and I wonder how good should I clean it up.
WD40 is basically mineral oil mixed with parts cleaner. Assuming you wiped it off right away and the labels are still stuck to the cell, I would think that you are OK, though it might be a good idea to let any WD that might have got in the positive vents to drain/dry out by leaving the cell upside down before using.
WD-40 is not mineral oil. It’s a petroleum distillate. It is safe for electrical circuits, if somewhat ‘greasy’.
It is NOT safe for any O-ring that is petroleum based (neoprene/Buna - usually black) as like dissolves like.
I’d not use it on silicone O-rings either. Hard to tell often WHAT Chinese O-rings are made of. If colored, pretty stretchy, and just a bit translucent > probably silicone.
And….its a poor lubricant. It’s a Water Displacement (WD….get it?) product.
wikipedia says:
“results of gas chromatography and mass spectrometry tests on WD-40, showing that the principal components were C9 to C14 alkanes and mineral oil.”
I would be tempted to use alcohol to clean out the mineral oil residue
I have tried Krytox and Dielectric grease. On large diameter lights, it is difficult to move the tail cap or battery tube because it is tight.
The best thing i found is sewing machine oil, applied very lightly or dry, no lube.
WD-40 means it is a Water Displacement formula discovered on the inventors' 40th try. It is not an "oil" as many believe. It is an extremely thin petroleum distillate product and dries out very easily without leaving any worthwhile residue to maintain a good lubricant quality on the parts that were sprayed. If anything it tends to attract dirt/dust, evaporates, and then nothing is left but the dirt. Any real oil, including sewing machine oil, is much better at providing lasting lubrication compared to WD-40. And as mentioned above WD-40 can work to soften or dissolve certain rubber parts like o-rings.
Here's what I use that will not wash off with water, is long lasting, and won't harm your flashlight o-rings:
I bought a 3oz tube of Permatex 22058 Dielectric Tune-Up Grease for spark plug boots years ago (and I expect I’ll be able to pass it down to my theoretical grandchildren someday at the rate I’m using it) and it seems to work quite nicely. It’s silicone based and has worked for me, so far. Also great for my pocket knife (a Kershaw Blur; I use it in the pivot as well as in the recessed spring ‘well’ inside the handle).
Unfortunately, Super Lube 93003 Silicone O-Ring grease is not compatible with silicone rubber according to their website (Super Lube Silicone O-Ring Grease ), which is used in a lot of flashlight O-rings.
tbh, I think grease is way too thick for a flashlights threads given that test show too much is worse than none, you are 100% guaranteed to get too much, and cleaning off the excess is nearly impossible, i sadly followed some advice in here…… do not buy the super lube grease. if you do, take the orings off and make sure it’s not globbed on.
Hornady one shot is guaranteed to go on thin but it’s a waste to use it on flashlights, just use a thinner lube and try to dry it off, the remnant is enough
There seems to be some conflicting info on silicon o-ring lube compatibility, and I am confused too, LOL.
Do we have any Chemical Engineers or Experts here at BLF that can clear this up ?
I found this and it looks wrong too.
. https://www.parker.com/Literature/O-Ring%20Division%20Literature/ORD%205700.pdf
.
2.2.13 Silicone Rubber (Q, MQ, VMQ, PVMQ)
Silicones have good ozone and weather resistance as well as good insulating and physiologically neutral properties.
However, silicone elastomers as a group, have relatively low tensile strength, poor tear strength and little wear resistance.
.
Heat resistance
•Up to approximately 204°C (400°F) special
compounds up to 260°C (500°F).
.
Cold flexibility
•Down to approximately –54°C (–65°F) special
compounds down to –115°C (–175°F).
.
Chemical resistance
•Animal and vegetable oil and grease.
•High molecular weight chlorinated aromatic
hydrocarbons (including flame-resistant insulators, and coolant for transformers).
•Moderate water resistance.
•Diluted salt solutions.
•Ozone, aging and weather.
.
Not compatible with:
•Superheated water steam over 121°C (250°F).
•Acids and alkalis.
•Low molecular weight chlorinated hydrocarbons
(trichloroethylene).
•Hydrocarbon based fuels.
•Aromatic hydrocarbons (benzene, toluene).
•Low molecular weight silicone oils.
.
Synthetic grease is basically artificially made vaseline without the big silica granules in it… and is considered “good compatibility” with silicone
I’m pretty sure very few if any flashlight orings use “natural rubber” and real silicone lube will blow up silicone rings so bad you will not be able to take the light apart… which leads me to believe most are also not using silicone
Responsible manufacturers would say what the orings are made of, and their dimensions…that being said, I think most of them use more overall compatible formulations.
Well, once upon a time, long long ago, I worked as a Chemical Engineer and had to use a slide rule to figure things out. Note, digital calculators and computers were not invented yet. For arithmetic we got to use pencil and paper since these were invented after chisel and stone.
I do remember a few things such as: O-ring selection is based on chemical compatibility, application temperature, sealing pressure, lubrication requirements, quality, quantity, and cost. Some typical O-ring materials are: Nitrile (Buna-N), Silicone, Fluorocarbon (Viton), Perfluoroelastomer (Kalrez®), Fluorosilicone, Ethylene Propylene (EPM, EPDM, EP, EPR), Neoprene, and Polyurethane.
Use of silicone o-rings is for static applications where they will be put in place and not messed with since silicone is relatively soft and subject to tear easily (silicone has poor tear and abrasion resistance and should only really be considered for static rather than dynamic applications). Therefore it's application for threaded connections is not recommended, i.e. flashlight threads. It is also more expensive than a typical synthetic rubber o-ring such as Buna-N, EPDM, or Viton, and over the production of 1000s of flashlights it is unlikely for a manufacturer to utilize a silicone o-ring in their flashlights due to relatively high cost alone.
I do not know of any of my flashlights that have silicone o-rings. If you have a flashlight (unicorn) with silicone o-rings that's great, then don't use a silicone based grease on them. If your flashlights are like mine, then super-lube with or without PTFE (or any equivalent) is fine as a thread and o-ring lube.
