Rust Worms

Looks like tin whiskers. This is usually associated with electrical components, but that is what it looks like.

Is the lock scalp truly stainless? Judging the stain lapping over the screw (is the screw stainless? Flat head screw indicates it is at least 40 years old) it appears to be rundown as opposed to direct corrosion. This may source from a ferrous component somewhere inside the lock chassis.

Thanks for the response. I'm am some what familiar with tin whiskers - though years ago. Thought there might be a similar phenome with SS. The screw is stainless and is about 2 years old. Based on report back from supplier the plate is stainless. The ferrous component is a by-product from the burnishing process and or sloppy manufacturing steps. I was just curious about the strange growth on the rust. Some close ups show the worms embedded.

"Some close ups show the worms embedded." Yes, I see them. They look like tin or zinc whiskers.

If you are certain all components of the lock are SAE 316 stainless, I don't know what to tell you.

As SolarEagle says, might be adhesive tape fibers.

Looks like duct tape residue, has somebody been taping the lock for easy access?

Don't know about mats.

Could the "worms" be microfibers pulled off something by the rough surface of the anomalous area?

Tom, we are working with the word 'worms'.

Are these (as I have assumed) inorganic vermiforms, or are the wiggling about?

Possibly "worms" was a bad choice. Let me change that to Fibers. To my recollection - they have not moved yet. However, look organic. I'm leaning more towards a metal fiber like steel wool. Two more shots different nodules.

trust me, it is MIC...

Toldjaso! =b

Both you and Rorschart get GAs. I submitted another answer before reading all the posts but I too think MIC. SRB are not likely on the surface of the lock as they are obligate anaerobes. They could have some anaerobic niche underlying the mat of iron where SRB could survive. These tubulars of iron protect the bacteria from disinfection like chlorination.

Tom,

I don't know about the worms... but to me, the rust appears to be coming from the screw holding the striker plate to the door frame.

When I enlarged the photo, it looks like a "negative screwhead" shaped mark directly above the screw in the lock plate.

Just my observation so I could be wrong...wouldn't be the first time.

Regards,
Sapper

i'm not sure if this applies to your situation. lately i watched a documentry about the titanic. there were "rustcicles"growing on the metal parts of the wreck.

there explaination was that it was caused by a microbe? that feeds on metal and makes formations that look like stalegmites. it is a living organism.

I am assuming that the ocean front door is exposed to a lot of potential water. And if so, then my suspicion is that the "worms" are really bacteria, Filamentous iron bacteria. These are individual bacteria that will extend themselves in tubular iron pipes. Viewing them at 20x magnification would be sufficient. They are faculative in that they can live in aerobic or anaerobic conditions. The filaments can be very long and become matted. I would be sure except for explaining a food source. Is the lock on a fish house? I am searching for an food source answer and a fish house would be an area where dirty hands may handle the lock frequently. The iron source could easily be from the stainless.

These are some of the same bacteria that will make the Titanic disappear in the near future.

thank you for repeating my post.

OP, does a magnet adhere to the lock?

The shape of that rusted area looks like a zinc plating has flaked off.

You only have the supplier's word on whether it is or isn't stainless.

Magnet is a quick check. Magnetic stainless (<312 ?) will still rust.

From the looks, it could be that the "latch" from the door, un-pictured, could be steel and be the cause of rusting due to a minute electrolytic action of dis-similar metals in a salty/moist air environment. This also could give a basis for MIC growth as mentioned by others earlier.

Thanks all for the interesting responses. To respond to some of the questions/inputs - The plate is none magnetic, The lock plate is on a beach condo and it is possible some organic substance was deposited on the plate. There is no rust or corrosion on on any other part of the lock. The frame the lock is contained in is aluminum - Electrolysis would presumably attack the least noble metal first. In all my experiences with rust on faceplate's I will see salt crystals embedded or in close proximity of the rust. On this specimen I do not see the salt crystals. The screw when removed shows only some rust on the ridge of the head.

Most latch bolts in these type of locksets are nickle plated brass or stainless steel. What is possible is the shaft holding the latch & return spring is corroding and intruding upon the surface of the face plate. JUST A THOUGHT.

The striker plate and latch are all SS. Though the lock latch hook makes contact to the keeper plate the opposing rusted plate is separated apart by 3/8 Poly Urethane bumper. There are no complaints about the keeper plate.

It is not the strike plate that I am speaking of . It is the mild steel shaft that comes out of the back of the SS latch that the return spring sits on this is not SS. It is where the spring sits and it can corrode when the moisture is high enough IE condensation with the temperature difference inside to outside you will get moisture and it tends to go out any way it can. this has been an issue for some time in the midwest due to the manufactures not lubricating these parts. Due in part from the manufactures cheapening things. And since we can not air ship anything with the type of lubricants that tend to be used in these parts have been deemed highly flammable according to FAA. Hince we can't air ship unless there are no lubricants used in these items. And do you think a contractor thinks of lubricating these items in the field not very often that I have found. Since I get to repair a lot of this type of hardware in the field almost all related to non lubrication. I've rattled on long enough, somebody around here has to work today. Duke

Okay - I understand. Thanks for the response.

I checked out the insides - no corrosion of any kind there and there was lubrication - go figure.

We have thousands of these out in the field, mostly beach front, that don't exhibit this problem. We have replaced this one and will wait and see what happens. Most likely wont see it again at this site.

I sort of suspect Rorshak Rorschatch Rorhscah the ink blot guy is correct. Makes the most sense after I consider.