When inspecting your spars, pay special attention to any fittings attached to the spars. Most spars these days are made of aluminum while the fittings are made of stainless steel. The dissimilar metals will lead to galvanic corrosion of the aluminum spar.
While it is impossible to see under or inside a fitting connection, there are some clues that can alert you to an internal compromises. Galvanic corrosion will cause bubbles to appear around the fittings under the paint.
Source: http://www.boatus.com/seaworthy/rigging/BUBBLES.jpg
When you look at your fittings, check to see if the paint is beginning to bubble. If you see bubbles, you need to address this area before the problem gets any worse!
Another sign of corrosion is white dust emerging from your fittings. This dust is aluminum oxide, usually resulting from galvanic corrosion with stainless steel fittings.
To avoid these issues, be sure to isolate the two metals. Plastic separators can be placed between the stainless steel and aluminum fittings and lanocote can be placed on the sides of screws and rivets to isolate them as well.
When you evaluate your rigging, take a close look at all fittings and make sure everything looks clean and perfect! Peeling paint is a preliminary sign that something might not be isolated.
