Aluminum vs fiberglass

Please excuse my cluelessness. I live in south Florida which is a fiberglass boat world. I am requesting information on aluminum boats. I am considering modifying an aluminum boat but first I want to learn more about them. For example, what are the positives and negatives of aluminum boats? I primarily fish salt water and would be concerned with oxidation of the aluminum boat. However, I assume that oxidation can be prevented with a zinc?

I have additional questions.
How do you repair a leak in an aluminum boat? Welding?
My interest is in fishing quietly in shallow water. Does aluminum float higher than fiberglass?

Any information would be greatly appreciated. Thanks.
Mike

I prefer aluminum to 'glass for sure. My fiberglass jon boat sits awful low in the water and has taken on water in some rapids before :lol:

Yes, a self etching zinc chromate primer will help prevent corrosion on the aluminum although you will need to paint it. One prob i run into is sand and debris stripping my paint job off of the aluminum thereby I still worry about the aluminum oxidizing.

I painted my entire boat with steel flex, most just paint the bottom, but there is no primer needed, and you can get a gallon for about 50.00... Seals it all up tight as well, Originally was gonna use bedliner, but guys here steered me to the steelflex after the bedliner company screwed me up...

There are tonnes of aluminum boats that are used in salt water.Theres 3 lobster rigs up here that are all aluminum,the north west has alot of aluminum rigs as well and pretty sure your coast guard boats are aluminum...seen a 47'er on you tube off of Texas.
That not to say there couldn't be a problem down the road.Any time theres metal and salt,corrossion is a possiblity.Even hooks left on the hull,will try to corrode.
Never ground anything to the hull,rinse it off,trailer/motor as well and use zinc annodes....and all aluminum will oxidize,thats how it protects it's self.
There are alot of different grades of aluminum,some people say not to use riveted hulls in salt,some companies will reduce their warranty or not even have one,if the boat is for salt water use.
Sorry for rambling...there lighter,which has pros and cons...opps, supper getting cold maybe I'll ramble more later.

I have run a riveted aluminum boat in brackish/saltwater on Mobile Bay & Miss SOund for 10 years. No leaks, no corrosion issued. A buddy of mine had a hull in the same conditions that was 25 years old w/no leaks.
Just keep it painted, wash it off every now & then & it will be fine.

All things being equal (length, width, gunwale height & beam), most aluminum hulls will be lighter than a fiberglass hull and will have a shallow draft. Also take less HP to get same speed out of the aluminum hull.

And where aluminum will bend, fiberglass will crack. But if you hit something hard enough to break either, you need to worry more about your lifejacket being on than what happens to the hull.
If you have a leak, depending on where it is & how bad, you can weld, tighten the rivets or use JB weld on it.

Fiberglass boats are great, especially for offshore and bigger bay boats. But for smaller boats in the 14-16' size, I think an aluminum hull has the advantage because of lighter weight, shallower draft and less HP. Also cheaper.

Aluminum hulls are easier to patch. Simple aluminum patches can be fabricated, riveted and sealed with 5200 marine sealant. Aluminum hulls can be beached on gravel with no worries of gouging gel coat. I own both , and each have their advantages. Don't worry about operating in salt water. Airplanes and helicopters operate in salt water environments all the time, and they are riveted aluminum. Just use common sense- wash the salt off as best you can, and inspect the areas around the rivets- that is the most likely place to get corrosion. In my experience you will spend more time fighting corrosion on your trailer and your electrical components than your boat. Go for it!

You do not want zinc anodes in direct contact with an aluminum hull.It will cause corrosion.A quality product like Steel Flex from https://www.fascoepoxies.com/products.html will seal and protect the hull.Do not use it inside the hull because it is slick as snot.I would use zinc chromate primer inside and then coat with a good quality Rustoleum metal paint from the local home improvement center.Your motor,the outboard and trolling motor,should be rated for salt water use and have zincs installed from the factory.Never ground or bond anything electrical to a boat hull.Fiberglass boats are extreamly heavy compared to aluminum boats.Aluminum boats run shallower and require less power to run.A typical 16 foot glass boat will have 90+ horsepower and an aluminum boat of the same size will have 30 to 60 horsepower.Of course some aluminum boats are built to run more horsepower.Less horsepower means better fuel economy.

Thanks for all the useful information. I am still a long way from starting a boat modification but it doesn't hurt to learn more about aluminum boats.

Thanks.
Mike

You can use the regular steel flex, you just need to add a texture to it... :mrgreen: After working with this stuff, If i was gonna to a grip floor, i would use steelflex and mix glass beads into it for texture myself...