Aluminium Cracked Boat Hull

[DaRipper]

Hi, first post for me,

i would like to get an opinion on a cracked boat hull and anyone that has had experience with it.

i purchased a new aluminum boat a year ago and about 6 months into using it i noticed a crack in the weld on the bottom of the hull, i had it repaired and the manufacturer paid me back for the repair..

it cracked again opposite the original crack and its the same kind of crack in the weld.

i only realized that it was cracked both times when i put the boat back on the trailer and there was heaps of water coming out when i removed the bung. water was pouring out of the bung for approximately 10 minutes each time. the crack is a hairline crack about 5 cms long.

 

i would not want to name the manufacturer at this stage as they have been helpfull and want to repair it themselves this time. i am just worried that it will crack again.. and it will become an ongoing issue, it is a 4mm offshore plate boat, i went to the boat show and in terms of space this boat is awesome, with plenty of fishing space i didnt see anything with as much space in the 6 - 6.5m range

 

i have never hit anything and have always been careful with transporting it etc..

 

has anyone had a brand new aluminum boat boat with a crack in the weld and had it repaired? Is this a fairly normal thing to happen with aluminum boats?? 😢

[kingie chaser]

The answer is simple!

 

Take it back to where you bought it!!

 

It should still be under warranty.

 

They will decide if its repairable or just replace it.

 

I don't why you wouldn't do this through where you purchased it from anyway?

Edited September 3, 2019 by kingie chaser

[kingfishbig]

I would call it unusual - and rather worrying. Didn't the manufacturer give some sort of explanation?

[DaRipper]

first crack explanation was the person welding must have made a mistake and humans make mistakes...

second crack explanation was the people that fixed it the first time must have done a bad job..

[achjimmy]

Welding can induce stress and cause further cracking . As above best sent back to the Manufacter to rectify . 

[GoingFishing]

Thankfully I've never experienced it. As with 99% of new boats alloy or glass they are perfectly fine out of the factory and of course there will be the very few that have issues. 

I wouldn't lose faith in the manufacturer just yet. They seem very willing to help and as others have already suggested, I would have got them to do the initial repair

[jeffb5.8]

As above send to the manufacturer and never source the repairer yourself as it leaves them a out to blame someone else's work.

Next make sure you keep all correspondence and take notes of phone calls, Who you spoke to, when and what they said.

Confirm all repairs come with written documentation, maybe they will need to remove the floor and while they do it will need a clean as the saltwater, could have come into contact with wiring / hoses ect.

You wont need the documentation until you need it, then you will be glad you took the notes and kept the emails.

P.s

You also catch more flies with honey than vinegar, so be as nice as possible to the staff, they can be your best hope and your worse nightmare, be clear what you want but don't be aggressive or rude.

[frankS]

Maybe it's not the fault of the manufacturer, perhaps it's how it's sitting on the trailer, perhaps it's how the trailer is towed with the boat on it.

A few years back I had a conversation with a guy at a boat ramp who was complaining that the boat was made poorly and it kept cracking the hull. I watched him drive off and he went over the speed humps at too great a pace and the boat took a horrible bump .

I know the trailer has springs and these are supposed to give a smooth ride to the hull but you have to take things slowly over humps and gutters etc.

Now it may well be a manufacture fault but on the other hand ?.

Frank

[Tunastrike11]

For welds to crack the aluminium sheets,plates are moving-flexing under load around the weld area etc so metal fatigue is happening causing them to crack need to strengthen the area.

[rickmarlin62]

Im with tuna strike  once repaired the area becomes fatigued from being heated when welded it may need some sort of rib or strengthening internally to stop the flexing  my mate had same trouble and after third sttempt sold boat back to where he bought it  and went glass

[kingfishbig]

1 hour ago, rickmarlin62 said:

Im with tuna strike  once repaired the area becomes fatigued from being heated when welded it may need some sort of rib or strengthening internally to stop the flexing  my mate had same trouble and after third sttempt sold boat back to where he bought it  and went glass

That make sense thought from DaRipper's post I'm not sure if it cracked in the same place:

"it cracked again opposite the original crack and its the same kind of crack in the weld".

[rickmarlin62]

Obviously movement an flex in that area  they dont just crack for no reason  especially in fairly new hull

[kingfishbig]

3 hours ago, rickmarlin62 said:

Obviously movement an flex in that area  they dont just crack for no reason  especially in fairly new hull

'Opposite' sounds like the other side of the hull. Yes, there might be the same problem of flex, lack of support, but it wouldn't be due to fatigue from being heated when welded.

Edited September 5, 2019 by kingfishbig

[back cruncher]

Hi all...to high amps or wrong welding technique can cause under cut in a weld.udercut is when the very edge of weld meets parent metal,and has cut into parent metal,reducing thickness of the plate.1mm of under cut makes your plate metal 1mm thinner,and so on.look closely on the edge of weld and see if it’s got under cut,use your fingernail to feel,or a torch to look for shadow.