Noise and aluminum hulls?

[djmeaney]

This is probably a dumb question, but that has never stopped me before!

I've read some post somewhere that stated aluminum boats are noisier than fiberglass boats. I'm curious what kind of noise are we talking about: water moving along the hull, vibration from the motor, or something else? I don't have much experience with aluminum hulls, and the majority of my fiberglass boat experience is in a sailboat -- where on a good day I'll hit 7 knots.

Dan

 

[ezmobee]

Re: Noise and aluminum hulls?

Water noise is a little greater.

 

[sschefer]

Re: Noise and aluminum hulls?

It all depends on the shape of the hull. Formed aluminum hulls like the StarCrafts are usually made of lighter aluminum and would normally be quite noisy but because they have a deeper V they slice the water very well and are only slightly noiser than a fiberglass boat. Interior carpet on the inside of the hull makes a huge difference. If your looking at aluminum boats like the North River, Rouge, Jetcraft, etc., then yes, these are going to be noiser becasue they do not have any compound curves that would allow for a deep V configuration. They tend to ride on top of waves and can give you a good and noisy pounding.

I should add that the advantage of the North Rivers, etc., is that the hulls are typically considered heavy aluminum up to 1/4" thick and are very rugged. They also require less draft making them far more desireable as river boats and when fishing in shallow water. My Jetcraft with the motor trimmed up (low water pickup) will run in about 8" of water. A jet will run in 6" easily.

 

[airshot]

Re: Noise and aluminum hulls?

Yes, they are a bit noisier, alum transfers noise better than glass and the alum is lighter so they have a tendency to slap a bit more in a good chop. In my life (60 yrs) I have owned 1 glass boat and had trouble with the glass seperating so that ended that. Then a number of years back we hit a steel drum floating in the river at a fair bit of speed and caved in the bottom of my center console alum boat. It was a total loss but she did not leak and got us safely back to shore, the real selling point of alum hulls came from the insurance adjuster. In his many years of experience with hull damages, it was alum hulls that survived and got the occupants back to shore, he told us that a glass hull would have shattered and we would have sunk like a rock. On that day I made up my mind to never go back to glass primarially for that reason. Noise or not I feel much safer in the alum hull.

Airshot

 

[64osby]

Re: Noise and aluminum hulls?

This is probably a dumb question, but that has never stopped me before! Dan

Dan I was alway taught there was no such thing as dumb questions, just dumb answers.

I went from an old FG to a Tinny this year, Yes there is more water noise when running. Some times we get spray noise on the hull and it does slap. We have a vinyl floor, I'm sure carpet would be quiter. No added noise at OB motor IMO, but my ears aren't that good any, just ask my wife.

 

[Pugetsound]

Re: Noise and aluminum hulls?

MY WIFE TELLS ME i HAVE SELECTED HEARING BUT I NEVER ANSWER HER WHEN SHE SAYS IT.

 

[sschefer]

Re: Noise and aluminum hulls?

On a lot of the thin aluminum hulls you often find heavy marine grade carpet glued to the insides particulary the sides above the chine and the bow area. This is done to deaden the sound and it does one heck of a job. Real fishing boats, not fish and ski's, rarely have the carpet because it would be really tough to replace it if it rotted on you. It's also a big time hook attractant.

Airshot, that's a really good reason to go aluminum!

One thing to watch out for with Aluminum boats is the repairability. The thinner boats are typically made with 6000 series tempered aluminum. When it's welded it looses 50% of it's strength and is prone to cracking in the heat affected zone (haz). For this reason, these boats are typically riveted. Many manufacturers of riveted aluminum boats will say that rivets allow a boat to flex and therefore last longer. The truth is, if it did flex the rivets would loosen and begin to leak very quickly. You would also stress the metal in those areas and create cracks.

So what's the big deal. Well if you tear a hole in a riveted boat that was built using 6000 series aluminum, you can't just cut it out and weld in a new piece, you have to find someone really good that can make a patch and rivet it on. There's only one guy that I know of on the west coast, he fixed my StarCraft but he wouldn't guarantee it. Fortunately, he did a beautiful job and it held up very well.

 

[barato2]

Re: Noise and aluminum hulls?

EH?