What oil (lubricant) to use for door locks and safe locks

[SlimJimmy]

Everyone knows about WD-40. But what you may not know is that WD-40 is not a lubricant, it's a solvent. Now, that's great if you want to get the gunk off of a lock or to free up some of the parts inside. But that's only the first part. Next you have to replace the lubricant you just removed. What I don't recommend is any lubricant that contains graphite. Graphite is great at making parts work smoothly, but the graphite will also dry out over time and gunk up the works. It also leaves that nasty black residue over everything.

So, what I recommend is a super lubricant that will free up the parts without leaving the black gunk behind. There are a couple very superior lubricants that locksmiths and safe technicians use. "Houdini" is one of them. The other, more expensive, alternative is "Tri-Flow. I use two types of Tri-flow - spray for gross penetration of lock parts, and "pinpoint" for precise applications, like on safe locks. I've included two links for you to compare.

https://www.triflowlubricants.com/all-products/

http://www.houdinilocklube.com/

[brush]

1. What about Three-in-One oil?

[SlimJimmy]

3. It's okay, but for locks, I highly recommend either Houdini or tri-flow.

They are far superior to all others.

For a really good comparison of many lubricants, go to the Houdini site and view the hour long lubricant video. To be honest, I have only used two lubricants as a locksmith and safe technician. All others just pale by comparison.

[rubbersole]

2. Thanks. I've been using graphite forever.

Not very often but it always works. It will leave black residue for the first few times on a key.

[SlimJimmy]

4. The problem is what's happening inside the lock with the graphite.

Even though it may not be coming off on the key after a while, it is still on the internal lock parts.

[Drum]

5. Is spray silicone a no-no?

Is that only for plastics?

[SlimJimmy]

6. Spray silicone is great at first, but will tend to harden or dry out over time.

If you want to use something that is longer lasting and won't dry out, use a white lubricant grease. But, as I said, for locks - I only recommend Houdini or Tri-Flow.

[Drum]

7. Thanks for the clarification and this OP--interesting and useful

[intrepidity]

8. Is PTFE ok? nt

[SlimJimmy]

9. Yes, PTFE is a good base for a lubricant.

Tri-Flow and Houdini are both PTFE based lubricants. Just as a point of interest, PTFE is the same coating that we find on non-stick cookware.

[intrepidity]

10. Right, that's the stuff I use

Glad to hear that you rec it. Can you think of any lubrication application that it would not be appropriate for? Like, eg, bearings? Or? TIA

[SlimJimmy]

11. I'm not sure if it's dielectric or not.

Meaning, okay to use near electronics. With lock and safe parts not being close to electrical parts, for the most part, I never really had that much of a concern about it. Good point though, and something I'll check on.

As to bearings, I would using something more robust like a white grease lubricant since the bearings would be under much more constant stress (heat buildup) than a lock or safe part.

[intrepidity]

12. Re bearings

Most recently I had a case where there was a brass sleeve bearing surrounded by a wicking material of some sort, only a small hole available to add lube. Was debating between 3-n-1 or PTFE and opted for the PTFE (i think it may be the same brand you show above). IOW, no way to add a solid grease (or do people melt it first? hmm hadn't considered that).

[SlimJimmy]

13. You made a wise choice opting for the PTFE as opposed to 3n1

3n1 is okay, but the PTFE is much better. When it comes to electromechanical locks (like the Kaba-Mas X-10) we use a white grease lubricant. It's fairly heavy, so it only goes on external parts like the dial housing, spindle, and protective sleeves. But it lasts forever. Okay, not forever, but for a very long time. I've never melted it, so I'm not sure if that would work. Also, I'm taking a bit of a guess because I rarely see metal bearings in locks or safes (except for the ball bearings embedded in the hard plate of some Liberty safes.)

One last thought. You could try the Tri-Flow pinpoint pen. I'm just not sure if you would get enough lubricant internally to do any good.

[Gavra Mead Barcelona]

14. What oil (lubricant) to use for door locks and safe locks

Last edited Tue Jan 10, 2023, 06:56 AM - Edit history (1)

How safe are these products? You can lubricate a door lock without chemicals or special tools. You will need a simple pencil to rub the key till a thick layer of granite appears. Then, insert the key into the lock, and leave it for an hour. The granite will be deposited into the lock, and a thick layer will remain on the key. I learned this life hack from the emergency locksmiths se20 agency. From the start, I was against any chemicals on my lock, and using a pencil to lubricate the keys seemed the safest way.