Wednesday, September 7, 2011

Screwed by Crevice Corrosion...

Time keeps flying and my desire to procrastinate hasn't gotten any better.  Frank finally received his HVAC license today.  For those who don't know what that is, it's a required license to work on refrigeration and air-conditioning units.  He's been studying with a friend from the marina, setting up weekly study groups to encourage each other to stay on top of reading and learning.  The idea behind this is two-fold.  One is so that we aren't reliant on someone else to fix our systems, and the second is so that he could potentially pick up work fixing up other peoples' systems while we cruise.  From what we understand, refrigerators and ACs are heavily relied upon and are frequently failing on boats.  This is a huge accomplishment for us for if he took a class at a trade school, it would've cost around $15K.  He was able to pass the test by studying the trade school textbooks and doing some hands on practice on old, used marine refrigerators.  I'm quite impressed; I can't learn from books!

Aside from that, we have been working on smaller projects in the past couple of weeks.  We have replaced one more chainplate and stay, and have even gotten our long awaited custom chainplate bolts.  Yes!!  As I'm writing, I'm realizing I had never posted this issue on our blog.  When we were removing our chainplates, we were finding the bolts to be in such bad condition due to crevice corrosion that you could literally tap them on a hard surface and they would fall apart.  Really scary!  Crevice corrosion has been haunting our dreams from the very start of our boating adventure.  We first encountered this nautical pandemic on our steel boat, where the stainless fittings would look sparkly new, only to randomly break on us, under very light loads.  Crevice corrosion happens when stainless steel is in a moist environment deprived of oxygen.  This generally happens where a fitting passes through a deck, or some other structure.  Anywhere where the stainless is exposed, inevitably, stays looking fresh and new, where it's deprived of oxygen, it actually turns into a sponge-like structure.  The steel corrodes out leaving only nickel behind.  This is why it's often recommended that the maximum lifespan of rigging on a boat is 10-15 years.  Couple that with the fact during the time of manufacture, Hans Christians in general, used stainless steel of inferior quality made in what people refer to as backyard foundries, which had nowhere near the quality control of their American counterparts.  This is a major issue with Hans Christians and Taiwanese built boats as a whole.  For the most part, this topic in the boating world is quite taboo.  A lot of people refuse to be believe that that shiny stainless bolt-head could be nearly corroded through right beneath the surface.  Out of sight, out of mind, I guess which to me is absurd as we are a floating case study of how stainless fails.  Anyhow as we went looking for replacements, we found that once again, these bolts were not available off the shelf and they had to be custom made.  We went with Fastenal, a nationwide hardware company, and worked with the salespeople to have a new set custom machined.  Of course, not surprisingly, the first time was not the charm.  Long story short, after an extended wait with the first set being totally wrong and sent back, we finally have the new ones on hand.   Thank God we don't have to worry about bolts for a long time.  

Crevice corrosion...

Not good..

Sooo pretty!

One week's salary :-(

We have also recently tackled the job of repainting the chain locker.  We had put this off for a while because we didn't want to have to crawl into what we call "the dungeon," and get fiberglass all over us, but we finally manned (or womanned) up and got it done.  The reasoning behind this was not solely cosmetic, but serves the purpose of allowing us to see any new leaks that may develop and basically track any water intrusion.  It was a good opportunity to look over our ground tackle and see the condition of our chain.  Some of which is, unfortunately, unsalvageable.  Another thing on the shopping list :(



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