Question:
I've got an 18ft Starcraft fishing boat. The problem I've got is that some
of the rivets that hold the hull skin on are starting to loosen. Some of
them are just loose enough to wiggle a little, others spin. I'd like to
seal or repair these rivets so I don't get any water in the boat. Not a lot
comes in but it wuld be nice to patch tings up. Inside the boat there is a
carpeted main deck and bow deck so the insides of these rivets are not
visible. I've tightened up loose rivets on an open style aluminum fishing
boat by pinging each rivet with a hammer while someone on the other side
holds a block of steel to the other side of the rivet. But I really don't
want to take my decking, tank, and interior apart.
Answer:
-Carefully drill the rivet out and replace it with an AL pop rivet coated with
fuel tank sealent
-The rivet should anneal again the
same shape. Rivets expand to fill the hole drilled and then press the sheet
metal together. Most any body shop should have an air hammer. Better yet,
I'd ask a trucking company or a bigger truck stop for some help. 'willing
to bet the guys that do the work on semi-trailers would do it cheap just to
have a change of pace. The rivets are the same on the boats as they are on
the aluminum trailers. They should have the rivets also.
-The closest thing to aluminum boat repairs is small aircraft. If you
know anyone who works on planes they have access to a bucking bars and
an air chisel looking tool to set them. You need a bucking bar with a
dimple approximately the shape of the rivet head although you could
make one with a small block of steel and drill the dimple. The same
goes for the air hammer, you can simply hammer on a rivet though the
result isn't as pretty. For rivets that can't be bucked due to
structural considerations such a decks in the way they make a
structural rivet called "cherry max". They come waterproof with a
solid sealing center and are expensive, nearly $1 each. I think
boatyards use something similar I saw years back.
It wouldn,t take an aircraft mechanic long to set a lot of loose
rivets with someone inside the boat holding the bar while he worked
the pneumatic hammer. He could easily drill out and replace bad ones
in a blink and you would have a first rate job when done. I know some
of these guys and they are always looking for work on the side and it
would be a lot cheaper than dealing with a boat yard.