Corrosion on rub rail - what would you do
- Thread starter redunculous
- Start date
you can stop it from going farther much easier than you can repair the damage... but to repair what has already happened, you will need remove the rail and cut away the damaged area and have a new piece of aluminum sectioned (welded) in... then redrilled as necessary.
From what I can see there is nothing really structural there to worry about. It is purely cosmetic. If you remove the stanchions and remove the corrosion with a dremmel tool. Build a small dam and fill with epoxy. Fair it in and paint it to match. The epoxy you replace the aluminum with will act as a insulation between the SS stanchion and the aluminum.
If you do some sanding, primer the damage area and tape ready for paint, use professional automotive color match paint that you can buy at O'reilly's, you should make it look like new for aproximate $65 or less depending the paint price and color code. O'reilly's got representatives that goes to the pier to color match, just ask for a manager to make arragements if you don't want to take it out of the water. Good luck
its aluminum.... it will protect itself once the stainless steel is not in contact with it any more.
im not exactly sure what the stainless post is in the photo that rises from the aluminum rail, but that needs a piece of plastic between it and the aluminum.... no metal to metal contact.
if you know much about galvanic corrosion, you know how it works, and if you dont know how it works, you can google it... galvanic corrosion between stainless and aluminum.
you need to separate the materials so they cannot work in unison to fight one another.. the least nobel metal will always be the loser
then scrape away the loose flaky aluminum down to the hard remaining stuff.... it will gray over and just be that way for almost ever without flaking any more.... painting it or applying epoxy may make it look slightly better for awhile, but it will eventually flake or come loose and then water will hold in next to the aluminum. which is bad... bare aluminum that can dry out will always be better and last nearly forever, where as aluminum that has water holding next to it will always corrode in time...
im not exactly sure what the stainless post is in the photo that rises from the aluminum rail, but that needs a piece of plastic between it and the aluminum.... no metal to metal contact.
if you know much about galvanic corrosion, you know how it works, and if you dont know how it works, you can google it... galvanic corrosion between stainless and aluminum.
you need to separate the materials so they cannot work in unison to fight one another.. the least nobel metal will always be the loser
then scrape away the loose flaky aluminum down to the hard remaining stuff.... it will gray over and just be that way for almost ever without flaking any more.... painting it or applying epoxy may make it look slightly better for awhile, but it will eventually flake or come loose and then water will hold in next to the aluminum. which is bad... bare aluminum that can dry out will always be better and last nearly forever, where as aluminum that has water holding next to it will always corrode in time...
Thank you for all responses
Centerline it's a stanchion for my lifelines - all are sat on the rail so I will now separate them all with a foot on each
Centerline it's a stanchion for my lifelines - all are sat on the rail so I will now separate them all with a foot on each
I certainly think that the previous responses are spot on. Appears from your pic that you've got a galvanic reaction between the SS stanchion metal and the aluminum toe rail. Electrically isolate the two to stop further corrosion. (Consider doing the same at each stanchion to toe rail interface.) Then simply ignore if the existing appearance doesn't offend too much. Probably no need to remove and replace the toe rail. This would be a huge and costly project. How it looks now by your picture is plenty strong enough.
Your corrosion into the silver anodized aluminum is certainly less objectionable than the same vis-a-vis my brown/bronze anodized toe-rail!
I have a 1980 boat that was constructed with numerous Al vs. SS locations so I also have issues. I think boat manufacturers originally considered that the anodized coating on aluminum would be enough to electrically separate the two metals. Or at least to be good enough that owners wouldn't notice the problem until well after any warrantee period expired. Turned out not to be the case over extended time in salt water environments.
These days, one would mount the two metals with some plastic in between, or first lay down a few layers of uv grade electric tape between (say) the base SS surface of a foot block screwed onto an aluminum mast. And any SS screws into aluminum need to be coated with the appropriate grease such as Tuff-gel or Lanacote at the least.
Your corrosion into the silver anodized aluminum is certainly less objectionable than the same vis-a-vis my brown/bronze anodized toe-rail!
I have a 1980 boat that was constructed with numerous Al vs. SS locations so I also have issues. I think boat manufacturers originally considered that the anodized coating on aluminum would be enough to electrically separate the two metals. Or at least to be good enough that owners wouldn't notice the problem until well after any warrantee period expired. Turned out not to be the case over extended time in salt water environments.
These days, one would mount the two metals with some plastic in between, or first lay down a few layers of uv grade electric tape between (say) the base SS surface of a foot block screwed onto an aluminum mast. And any SS screws into aluminum need to be coated with the appropriate grease such as Tuff-gel or Lanacote at the least.
My knowledge on electrical isolation is poor I must confess but I will research and start work on it
Thank you for all the info
Thank you for all the info
Yeah... I was going to recommend JB Weld. A little JB between the SS bolts and the aluminum might help with isolating the two as well.
