Managing Rust on Galvanized Trailer

[Tortuga]

My 1994 Pacific Trailer is starting to show it's age. It's galvanized with a C Channel frame -- and it's pretty bulletproof. The brakes, springs, bearings etc have been regularly maintained and replaced as needed. But, the frame rust -- which has been minimal until this year -- is at a point where I need to intervene. There are a couple of spots where the rust is starting to look structural -- such as the aft corner at the bunk channel/ support. And, there are several spots that are superficial and look like they may be repairable with some scarping and painting.

Any ideas?

Thanks!

Matt

[localboy]

Having dealt w/ rust on old cars, I can tell you this. I HATE IT. I've used various "encapsulaters" by various companies. All worked, to some degree but I've found this seems to have held up the best and it has no requirement for difficult, time consuming surface prep and does not require a top-coat (like POR 15 does).
Mind you nothing I noted is scientific, just observations, comparison etc. I've used it on exterior metal and it seems to hold up. One place I used is under a 50 yr old VW bus to cover the joint between new metal panels and old, original German steel after MIG welding together. I used the black on the rear of newly chromed bumpers; same results.

Only disadvantage is any left over material will harden, even in the can, once exposed to air (but a lot of them are like that).

http://www.rustbullet.com/?utm_source=bing&utm_medium=cpc&utm_campaign=GenRustUS

[Blueback]

[Tortuga]

Thanks for the quick replies. My only concern with the encapsulators is whether rust can continue to fester under encapsulation. I'll scrap off as much as I can, but there will clearly be residual rust under the paint.

I don't expect miracles. The trailer is 20 years old so I only expect another 20 years.

[letitride]

Blueback is right on the money, every boater with a galvanized trailer should have the cold zinc galvanized spray paint in there tool kit....

To remove rust, I use a wire wheel on a 4" grinder (wear eye protection and some protective cloths, the wires some time come off the wheel at very high speed) it will remove most of the rust for the super tough rust you can use the grinder wheel and remove it, once you have removed all of the rust.

Coat it with the cold galvanized zinc spray paint as Blueback recommended, I keep a can in my truck and ever time I launch my boat I inspect the trailer and spray a coat over any and all very light rust spots to keep it from continuing to rust since the boat is in the water you don't need to worry about over spray getting on the boat..... The spray paint makes a mess and takes a long time to dry, best to do this at the launch ramp also make the trailer look new and clean.....you might find yourself just spraying away......as I often due, also be careful about the spray paint rules for your city and or the launch ramp in your area.

I even will spray this on my hot dip chain if I see some of the hot dipped zinc coating getting thin....Zinc is your friend.

Also if you grind away the zinc coating and expose the bare metal steel you can re-weld the steel with more un-coated steel to make it stronger if you have holes, just add more steel. I just turn the power up to max on my Mig welder 220 volts and get the steel glowing red....super hot it will burn the zinc away and you can get a solid steel weld and lay a nice looking bead down, be careful and wear some type of gas mask because all the fumes they are very toxic. Better to pay some one to re-weld and then coat with the cold zinc spray from the can multiple coats as required - it works....did this to my trailer when a thru bolt broken and two steel beam pieces came apart at the launch ramp, I welded steel beam to beam at every thru bolt joint and it has held for 5+ years didn't want to have that kind of failure while towing


I am sure others can probably explain it better than I, my two cents...

[Blueback]

[quote="letitride"]Blueback is right on the money, every boater with a galvanized trailer should have the cold zinc galvanized spray paint in there tool kit....

To remove rust, I use a wire wheel on a 4" grinder (wear eye protection and some protective cloths, the wires some time come off the wheel at very high speed) it will remove most of the rust for the super tough rust you can use the grinder wheel and remove it, once you have removed all of the rust.

[u]Coat it with the cold galvanized zinc spray paint as Blueback recommended, I keep a can in my truck and ever time I launch my boat I inspect the trailer and spray a coat over any and all very light rust spots to keep it from continuing to rust since the boat is in the water you don't need to worry about over spray getting on the boat...

Hi letitride-name? Geoff here "Blueback". You have 2 approaches it would seem -1 grinding off the rust prior to the application of CG or 2- applying over the tight rust at the launch site.
Question -- how has the spray over tight rust held up?
Question: [/img]

[journey on]

My experience on rust is dealing with old equipment, such as the '63 chevvie or an old machine. For a while I lived down by the ocean and everything iron rusted, the aluminum corroded.

So, my first thought is that grinding never gets rid of the rust. Sandblasting never gets all the rust out. Covering a freshly cleaned surface just lets the rust build up. Cold galvanizing, which I use, is great on new metal, but it's not as good as hot dipped galvanizing. I have to re-coat the galvanizing paint, where it wears off the metal, and never had to do that with hot dipped galvanizing.

Any way, here's what I use, and since I'm rebuilding the front end of the chevvie, I use a lot of it. First get rid of all the rust you can. A wire wheel is good, as is steel wool (stainless.) If you're really into it, sandblast. Then spray a coat of Rust-Oleum Rust Reformer. Let that dry overnight and then cover it with a coat of good spray paint, such as Rust-Oleum Professional. I believe that the Rust Reformer not only changes the surface rust to iron sulfate, but is a primer. If I've got it wrong please let me know. And it's all in spray cans, so you can use it on multiple jobs, over a period of time.

I think this is what the Por-15 deal is, since they use a phosphate coat and then the black paint. All I can say is that the Rust-Oleum stuff works better for me.

Anyway, the Rust-Oleum has worked well for me. Also, 20 years out of a galvanized trailer is impressive to me. We've got 10 years on the trailer and it's showing some rust.

Boris

[Blueback]

[
Hi Boris--
If it works for you -great- yes hot galvanizing has been the key protection for new trailers. It, as you know, is zinc -- a sacrificial metal - which has a limited life span - but works. The Cold Galvanizing does the same and the specs are:
GENERAL PROPERTIES: ZRC® is a high-quality cold galvanizing compound based on a trade secret organic binder which affords true galvanic anti-corrosion protection to metals. The dried film of ZRC is 95% metallic zinc. Because of the uniqueness of the formulation, ZRC is the only coating of its type to be recognized under the Component Program of Underwriter's Laboratories, Inc.
Geoff

[letitride]

[quote="Blueback"]

Hi letitride-name? Geoff here "Blueback". You have 2 approaches it would seem -1 grinding off the rust prior to the application of CG or 2- applying over the tight rust at the launch site.
Question -- how has the spray over tight rust held up?
Question: [/img][/quote]

Nice to meet you Geoff, my name is Paul, covering light rust with CG has worked very well on all 3 of my galvanized trailers, basically if you have some bolts that are bleeding rust on top of a galvanized coat then cover it up...been doing this for the last 7 years with great results, the rust does not seem to re-appear. My winch handle for example was looking really ugly zinc coat must have been poor quality this is a non critical component for towing...I used the CG on it a few coats and 3 yrs later looks great still, I have experimented on all of my trailer components and it works....

If your trailer is already de-solved and looks like Swiss cheese CG is not going to make it strong again, but it will stop the rust from attacking the steel.

Also if you look closely at your trailer you can see the galvanized coat turns different colors along some beams depending on how much of the zinc has dissolved over time and exposure. I usually add some CG and thicken it up before the rusting starts....best $$ I have spend + a clean trailer at the launch ramp means your proactive not re-active....you know what I'm talking about you can tell who take care and who doesn't....at the ramp.

Enjoy,
Paul

[T.R. Bauer]

I think CG is a reasonable way to prolong the life of your trailer. I use it all the time when I fab and weld stuff up for folks on trailers and I think it works very well. In reality, there isn't much else you can do anyway.....except buy a new trailer.

[Blueback]