The hinges and other hardware for my trailer doors are rusting - again.
A few years ago I removed all of the hardware from my trailer doors
(hinges, lock hasp, cam keepers, bar retainers, etc) and removed all the
old finish and rust with a wire wheel on my bench grinder.
I then dipped all of the parts in a clear finish that was supposedly made
to prevent rust. I'm pretty sure that the product was recommended in this
group, but I don't have any left so I can't tell you the name. What I do
know is that it didn't really last very long. When the parts were first
coated, they looked great, but less than a year later the finish began to
peel off and the parts started to rust again. Now, 3 years later the finish
is cracked, crumbling and peeling.
The finish was like a thick coat of polyurethane, but I know it wasn't just
polyurethane, it was something specifically made for coating metal that was
exposed to the elements. When it was first applied, the bright, shiny metal
showed through but today the parts are black where the finish hasn't peeled
off and rusty where it has.
So, short of replacing ~$100 worth of door hardware, what are my options
for refinishing what I have? If I clean all of the parts again is there
something that will prevent rust for a significant number of years? I
considered spray paint, but I'm not sure how that would look. It's
certainly not going to look like real metal.
Suggestions welcome. Thanks!
Looking at your photo, I'd say that your cleaning job was less than stellar.
Scale like that takes a while to develop; and as it does, it pops the paint.
I'd suggest you...
1. remove hardware
2. chemically/physically remove paint
3. physically remove the rust & scale that is easily removeable
4. remove the rest of the rust galvanically
5. paint immediately
6. top coat if desired
Neither that nor anything else will keep the hinges from rusting where one
knuckle rides over another...whatever you put on them will eventually wear
away. The only permanent solution is SS, bronze or brass (or monel, do they
make monel hinges?). Including the pins.
I'm not sure how you came to that conclusion. When I was done cleaning the
hinges and other parts there was absolutely no rust on any part. What I
couldn't get with the wire wheel on my bench grinder, I got with my Dremel.
I then wiped all parts down with mineral spirits before dipping them in the
coating and hanging to dry. As I said in my OP, the parts were bright and
shiny and looked great after they were recoated.
What's your definition of "a while"? I don't recall when I did them, but
it's probably been at least 4 - 5 years, maybe more. Keep in mind that the
finish started peeling off in roughly a year, exposing the metal
underneath, so we're looking at at least 3 - 4 years of exposure in salt
Just to make sure we are on the same page, they were not "painted" They
were dipped in a clear coating made for metal that was supposed to prevent
rust. I wish I could find/remember the name of the product, but I can't.
Someone else suggested the cold galvanizing compound. I've look into that
and it will probably be the way I"ll go.
You can make scale nice and shiny but it is still there. IME, wire brushing
won't remove it, just shines the surface. The only way I know to get it off
is to chip it off; a chipping hammer works well but any hammer and a cold
chisel works too.
Phosphoric acid is normally applied to shiny metal to etch it. It also
converts light rust, turns it black. Additional converter can be added to
heavy rust. Then primer. I normally use a self etching primer.
Not arguing, just wondering...
Once the hinges and other parts were wire
wheeled and smooth and
shiny, there was nothing to "chip off", at least nothing
Imagine 16" of smooth metal. What would I take a chipping hammer
or cold chisel to?
----Android NewsGroup Reader----
Ok, so now you've confused me. First you said my cleaning was less than
stellar, to which I replied that it was nice and shiny. Then you said shiny
doesn't mean no scale, the scale could be shiny and it needs to be chipped
off. When I asked what I would chip off if the metal was shiny, you say
"nothing if there was no scale."
So does that mean my initial cleaning was indeed "stellar"?
I have no idea. There appears to be scale in your photograph; usually, it
takes a fair amount of time to develop. If there were scale there before it
could easily have appeared shiny after wire brushing. Was it there? I
don't know, didn't see it. You did.
When I say scale can be shiny and metallic, here's what I mean...this engine
has tons of scale but note particularly the area in the center near the
Ok, got it.
Take a look at this photo. One is a before, and one is an after. I may do a
little more wire wheeling on the after, but what is your opinion at this
point? Do you see anything that you would consider scale, as opposed to
This is basically what all of the parts looked like when I went through
this exercise a few years (4 - 5?) ago.
I haven't read every post in this thread, so if someone has already made
this suggestion, my apologies.
If I wanted to coat something steel so that it would last forever, I
wouldn't even consider a paint or a clear coat. I would have it nickel
plated at any shop that does chrome plating.
Nickel is a fairly hard metal, so even if these hinges have wearing
surfaces on them where they rub against other metal surfaces, the nickel
plating will outlast any other coating on that same surface.
Electroplated coatings are probably the most durable coatings you can
put on metal.
Nickel is an important metal in making stainless steels because, just
like chrome and many metals, it forms an oxide film over itself that's
extremely impermeable to air and water. So, the formation of that oxide
film protects the underlying nickel from further oxidation. It's so
thin, in fact, as to be invisible. That's why nickel and chrome don't
appear to "rust". The oxide film they form is only a few dozen atoms
thick, and light passes through it almost unaffected.
(Gold and platinum don't form an oxide film AT ALL. Most metals form
some oxide film over themselves.)
In metallurgy, there's a general rule that when you mix metals, the
properties of the alloy will be largely determined by the properties of
the parent metals. So, if you mix a lot of nickel and chromium into
iron, you get a steel that forms an protective oxide film over itself,
just like nickel and chromium do. That's exactly what the various kinds
of stainless steels are; iron with enough other stuff in it to make it
behave like that other stuff.
So, if you can't buy stainless steel parts, the best alternative would
be to have the ordinary steel parts nickel plated to give them the same
self healing oxide film that stainless steel has.
It looks good, can't see anything obvious although there are a couple of
darker spots near the bottom at the edges of the right raised portion that
might be suspicious. If the raised portion around the spots can't be
knocked off it looks good to go.
Nestork sugested nickel plating. A good suggestion. Another alternative,
if the items are small enough, you could hot dip galvanize them. I'm not
talking about zinc electroplate, I mean dipping in molten zinc which is
easily melted on a gas stove.
Either will protect very well unless the coating is breached. Which it will
be at the hinge knuckles; about all you can do there is apply some oil once
in a while.
One thing I wouldn't do is use whatever you used before. I've been
wondering about that. You said it was clear but turned black. Red rust is
reduced to black "rust" by acid. Could your clear stuff have been acidic?
If so, I wonder if it remained so after drying? And if it did, how did new
rust form for it to reduce? Was it air/moisture permeable? Was it supposed
to be primed/painted? If so, was it to act sort as a "court of last resort"
if the paint barrier was breached? Understand, I have no idea, just
Val-Oil is what I used. I just found an old a.h.r post where I asked for
opinions on it, but no one responded. It was back in March '09, so the
parts were redone a little over 5 years ago. The Val-Oil was recommended by
a guy in an independent paint store.
Like I said, the parts looked really good when they were first done, but
now, besides the rust, the finish is peeling off in sheets. Now that the
parts are off and I can see them in good light, I'll take back the "black"
coloring comment. It's more like dark brown/grey, as shown here:
I'm going to try the RustOleum Cold Galvanizing Compound. It can't do any
worse. If I was going to consider the whole nickel plating or hot dip
galvanizing route, I'd just drop the $100 bucks and buy all new hardware
Thanks for sticking with me on this one. While I was searching for my old
post I came across another thread where I asked about rust back in '09 and
you participated in that thread also. You're really into this rust thing
aren't you? ;-)
I live for rust. A day without rust is like a day without
sunshine...without a bird's song...without a lover's touch...without a
Fortunately(?) there are few rust free days for anyone :(
Here's a before and after picture.
Before, just a hinge...
After, mainly a hinge, but also a cam holder and closure bar clamp in the
bottom left. The parts were refinished with the Bright Galvanizing Compound
after all of the old finish (Val-Oil) and rust was removed with a wire
wheel on a bench grinder.
As you can see, the parts are more of a bright gray than the normal silver
you'd expect to see as hinges on a trailer. I also cleaned up the rusty
carriage bolt heads and sprayed them. At 85 - 90 cents a piece at HD I
didn't feel like replacing all of the bolts required (24) when all they
needed was a quick cleaning with the wire wheel and then a quick spray with
Regarding the scaling you mentioned, one of closure bar clamps (the one
shown in the picture, in fact) had considerable scaling which, as you
pointed out, did not come off with the wire wheel. It will be interesting
to see if that one acts any differently than the other parts. It is subject
to more moisture being on the bottom and so close the ground. It was by far
the rustiest of all the parts.
We'll now just wait and see how the compound holds up on the various parts,
especially the parts subject to movement, like the lock clasp and hinges.
Thanks again for the advice.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.