Jeremy
19-09-2007, 07:20 AM
I lifted the floor of my tinny up for routine maintenaince on Sunday arvo and found some pitting in the bottom. Don't remember whether it was there last time I cleaned about 12 months ago, but it is enough to make me worried. The boat is about 15 years old heavy duty Stessl tinny with 3 mm bottom I think.
I did find what looks like a badly rusted steel maundrel from a rivet in the area the pitting was worst. There is some minor pitting throughout most of the floor, but it was most concentrated and worse in that area. I have now cleaned the hull thoroughly. There are a few stainless bolts and fittings on the boat. All the stuff done in the last few years I have been careful to isolate from the hull with rubber and/or that yellow cadmium stuff, but there are some older fittings (all stainless bolts above water level) which have not been properly isolated, but there is no pitting near these. I do not isolate or disconnect the battery in between trips, but I am sure all the wires are properly insulated and it is not earthed to the hull.
Few questions:
1. can the steel maundrel cause the pitting in the aluminium? I though it was only metals with a lower corrosive index like lead, stainless and brass.
2. is there anny point putting lanoguard or tectyl on the pitting to help prevent corrosion?
3. If the cause of the corrosion is removed, will it stop, or will it keep going now that it has started?
Thanks!
Jeremy
I did find what looks like a badly rusted steel maundrel from a rivet in the area the pitting was worst. There is some minor pitting throughout most of the floor, but it was most concentrated and worse in that area. I have now cleaned the hull thoroughly. There are a few stainless bolts and fittings on the boat. All the stuff done in the last few years I have been careful to isolate from the hull with rubber and/or that yellow cadmium stuff, but there are some older fittings (all stainless bolts above water level) which have not been properly isolated, but there is no pitting near these. I do not isolate or disconnect the battery in between trips, but I am sure all the wires are properly insulated and it is not earthed to the hull.
Few questions:
1. can the steel maundrel cause the pitting in the aluminium? I though it was only metals with a lower corrosive index like lead, stainless and brass.
2. is there anny point putting lanoguard or tectyl on the pitting to help prevent corrosion?
3. If the cause of the corrosion is removed, will it stop, or will it keep going now that it has started?
Thanks!
Jeremy