mast deterioration -- at tne base

[crieders]

As I began winterizing the boat I notice that the mast paint at the bast is bubbling and looks deteriorated or perhaps like their is corrosion. I am concerned about the itegrity of the unit on this 1990 tall rig boat. I was just going to sand it flat and use a primer and paint. Is this a common problem and how wrorried should I be? Thanks. Cliff Rieders, Dream Extreme, 34 tall rig, 1990

[Stu Jackson]

Cliff

We have the same condition.  When we pulled our mast four or so years ago, I didn't think to check the material of the mast shoe, and should have instructed the yard to put Lanocote on the shoe between it and the mast, in any event.  The bubbling paint is similar to the conditions around the pop rivets on the mast and boom.  Unless the base of the mast has corroded so much that the mast material has split and is starting to turn up (which I've actually seen -- not on C34s) I don't think you have a structural problem.  I was planning to clean mine up just as you have suggested.  It will continue to corrode "inside" until you pull the mast again, clean up inside and the mast shoe,and Lanocote the whole area of contact between the shoe and the mast.  That is, if they are dissimilar metals.  Another contributor could also be from standing bilge water.  It's a pretty rotten environment down there.

[Ron Hill]

Cliff : I had the same "bubbling" at the base of the mast where it fits into the shoe.  When I pulled the mast a few years ago I found no pitting of the inside of the mast or the shoe - Both are aluminum alloys. 
I sanded the outside lightly and found that Interlux "Bright White" is a perfect color match for the Enron(sp?) mast paint.

The "bubbling" has not reappeared.  My guess is that the rain coming down the mast caused the bubbling as I docked the boat in fresh water for it's first 16+ years.   

[Rick Johnson]

Ron,

I've got the same problem with my mast and I have been holding off on fixing it (I was afraid I would make it worse).  Once I've sanded the area down, do I need to etch the aluminum?  What type of primer do I use?

Thanks for any help,

Rick

[Ron Hill]

Rick : I didn't use any primer, just cleaned the sanded area with lacquer thinner/acetone. 

[crieders]

Thanks for the replies. I guess I was looking for an excuse to pull the mast. How is it affixed? Thanks again. Cliff c34, tall rig, 1990 #1022

[Stu Jackson]

Cliff

What makes you think it's attached to anything?   

The mast is hollow.  There is a big piece of aluminum called the mast step that's screwed into the athwartships framing that the mast fits around pretty tightly -- it just keeps it from moving in any direction at the base.  Before they re-stepped my mast, I went and got "traditional":  there was no coin on the mast step, so I installed a "Loonie" Canadian coin.  Have had great luck ever since.

The mast step is almost akin to the ball base of the Garhauer dinghy motor lift, just keeps the base from shifting.  The partners (where it goes through the cabintop), the turnbuckle from the cabintop to the mast inside and the shrouds, backstay and forestay keeps the rest of it up.

Sorry I don't have a picture, must be one of the "pre-digital" photos I took, and the scanner doesn't work anymore since I changed computers.

Anybody know how I can get a driver for an old scanner?  (Sorry, not a boating question...shame on me!)

[crieders]

Pardon my ignorance but whats a "coin"? Thanks. Cliff c34, 1990, tall rig, #1022

[Stu Jackson]

Cliff

Coin, as in nickel, dime, quarter, "coin of the realm."  In ye olden dayes, they'd put coins under the mast for good luck.