Hairline cracks in 2020 228 hardtop?

[luckydude]

Take a look at http://mcvoy.com/lm/phone/2024/33.html and hit the space bar to go to through 5 more pictures. See the hairline cracks?
Easier to see on a computer.

Are those normal or do I talk to Grady about them? And, yes, they were all there before I took the top off (I'm replacing it with a pilot house).

 

[glacierbaze]

Lucky, you are giving access to a lot more than 5 pics, including some personal notes.

 

[luckydude]

Lucky, you are giving access to a lot more than 5 pics, including some personal notes.

Yeah, sorry, fixed. It wasn't anything super secret but no need to be there. Thanks!

 

[SeanC]

Are they cracks or scratches do do with the welding process.? Are you sure they weren't there before?
If you look at the edge of the of the aluminium plate in photo 1 do the cracks extend into the plate?

 

[seasick]

It's hard to be sure but the cracks being so straight are probably due to movement of the hardtop coring relative to part of the outer edge molded lip. I can't say if they are normal, nor can I be sure if they are structural but since the separation is so uniform, I would be less concerned.
I am not sure what the intent is for possibly contacting Grady. You removed the hardtop didn't you? Are you going to reinstall it over the pilot house??

 

[DennisG01]

It would be enough of a concern for me to at least check them out better - and I would definitely get your dealer involved.

 

[rocketguy88]

Two things of note:
1. The cracks is along the entire width of the beam, so it's definataly propagated from wherever it started from (picture 33/38)
2. It's outside the weld (again, picture 33/38)

So to me it's in the metal, not in the weld. Which is more concerning to me as if it was the weld then easy fix. Just re-weld it. But that doesn't appear to be the problem.

Now onto the root cause. The hardtop will flex as the boat moves thru the waves. It's called deflection and I'm sure Grady has modeled the deflection using Finite Element Analysis (FEM). Then they can calculate exactly how thick the tubes need to be, tube arrangement, how thick of a weld, etc is needed to allow the machine to work under normal loads.

Back from the two aircraft structures classes I took in undergrad aerospace engineering, an aircraft wing deflects upward in flight due to the force of lift acting upward on the wing. Aircraft wings are designed to have enough strength to enable the lift force from tearing the wing apart. A hardtop is going to deflect side to side as horizontal forces act on the boat (e.g. beam sea) and upward and downward as vertical forces act on the boat (e.g. head sea).

The hardtop is allowed to deflect some, but the main concern to me is how DEEP are those cracks going into the metal? If the cracks too deep then a catastropic failure can occur.

David

 

[wspitler]

I believe those are nonstructural surface cracks caused by the welding (heat distribution impacting the anodizing). I'd call the company that built/welded the supports. Mine has very similar marks in a few places, not quite as evident as yours. My 330 was built by WMW Marine in Winterville NC. I'm sure any non-destructive inspection process such as dye penetrant would show them to be surface imperfections.

 

[luckydude]

The thing that has me worried is the vertical cracks are on both sides of the plate and they match.

The reason I care is I'm selling the hardtop to a friend, I want it to be in good condition.

I'll be talking to the dealer as well.

 

[wspitler]

The thing that has me worried is the vertical cracks are on both sides of the plate and they match.

The reason I care is I'm selling the hardtop to a friend, I want it to be in good condition.

I'll be talking to the dealer as well.

Please let us all know what you find out. I’m sure this is more common than we could imagine.

 

[Fishtales]

interesting. Looks like a bad weld from the one pic I could see.

 

[luckydude]

interesting. Looks like a bad weld from the one pic I could see.

The guy building my pilot house thinks that it might be trails from the welder dragging the tip. I'm gonna carefully compare front and back to see if the "crack" line follows the same path.

 

[Don Davis]

I had a few cracks in 2 of the uprights on my 1999 Seafarer when I bought it a few years ago, my son in law welded them for me. I realize mine is much older but I was shocked to see them, I’ll grab some some pictures of the location and the welds

 

[Don Davis]

Here’s pictures of the welds to fix the cracks, fairly extensive…

 

[SeanC]

The guy building my pilot house thinks that it might be trails from the welder dragging the tip. I'm gonna carefully compare front and back to see if the "crack" line follows the same path.

I thought the same. I have a feeling mine have the same. I’ll look next time I’m at the boat.

 

[jjack5150]

Cyclic loading cracking the hardened anodized surface? See if they can polish out. If not the loading has penetrated the aluminum.

 

[luckydude]

Cyclic loading cracking the hardened anodized surface? See if they can polish out. If not the loading has penetrated the aluminum.

That's my plan, great minds and all that...

 

[Legend]

Would not hurt to get GW involved since the hull is under warranty ( not sure if hull GW definition includes the hardtop)

 

[luckydude]

Would not hurt to get GW involved since the hull is under warranty ( not sure if hull GW definition includes the hardtop)

We're gonna see if we can buff them out, if so, they aren't cracks, just weird welding technique. If not, absolutely gonna get Grady involved.

 

[family affair]

We're gonna see if we can buff them out, if so, they aren't cracks, just weird welding technique. If not, absolutely gonna get Grady involved.

Try it 1st in a less obvious spot. If you buff it, you will remove the clear anodizing. If you determine it is in the clear anodizing only, leave it alone.