Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

[nilaszewski]

Okay, I don't really even know the right terms for these but wondering what your opinion is? My Live well was leaking so I drilled out all the rivets and pulled the liner to get at the drain. Thats when I noticed that those stringers/bulkheads are all cracked. This will be the 4th summer owning this boat and I don't have all that much money to spend on it. In all honesty I kind of wish I would have never seen them. I guess I'm wondering if this is a huge safety issue?

The easiest thing I can think of it so remove them and have them welded back together out of the boat and then rivet them back in. This would eliminate the need to remove all the foam and gas tank. Do I even need to fix this? I always planned to re carpet the boat and re-buck the hull but could never decide if I wanted to sink the money into the boat or just sell and upgrade to newer. I would feel bad selling the boat now knowing these was an issue, so that is out an option.

So back to fixing it or not? Thoughts?

1995 Princecraft Pro 178.

https://drive.google.com/file/d/0Bzs9s1AxH9qrLTg3dXVweVlDQUU/edit?usp=sharing
https://drive.google.com/file/d/0Bzs9s1AxH9qrNHBYNUFRQnRQN28/edit?usp=sharing
https://drive.google.com/file/d/0Bzs9s1AxH9qrNVR0VnM5TlFsVVE/edit?usp=sharing
https://drive.google.com/file/d/0Bzs9s1AxH9qrR1VxcjFPeHNHMkE/edit?usp=sharing
https://drive.google.com/file/d/0Bzs9s1AxH9qrRUMyMWY4Q3hKRm8/edit?usp=sharing
https://drive.google.com/file/d/0Bzs9s1AxH9qrSVJnWHFTdHFNME0/edit?usp=sharing
https://drive.google.com/file/d/0Bzs9s1AxH9qrTkowejZ2ajRvdzg/edit?usp=sharing
https://drive.google.com/file/d/0Bzs9s1AxH9qrbENTeEgxZnlUSmc/edit?usp=sharing
https://drive.google.com/file/d/0Bzs9s1AxH9qreHhyNmpfU285TjA/edit?usp=sharing

 

[greenbush future]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

If you have structure damage in this location, where else on the boat "could" there be more? I'd be inspecting all of the stringers and bulkheads, then making a decision about what if anything needs to be done. Pay attention to critical areas like the transom strength too.

 

[jbcurt00]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

IMO, NOT good, not good at all. All those ribs & bulkheads are part of the structure of the boat. Sort of like your ribs. Can you function w/ cracked/broken ribs, yep. Play basketball, yep. Will it be a pleasant experience, nope. Is there risk of damaging other stuff, yep.

Some of the tin resto's over in the Starcraft forum have extensive cracking of rib ends at the rivets, not unlike yours. Often in combination w/ cracking along the chine (in the exterior hull above the cracked ribs, or the spray rail) or cracking of the hull at the cracked rib end thru rivets.

I'd recommend that you open a free photobucket acct, or figure out a way to post your google drive pix IN your posts. You can post 6 pix per post & can never post too many. Having the pix IN your post makes it easy to scan back & forth between what your typing & looking at the pix, rather then having to open an attachment or wait for another site's server to load the pix in a new browser window. As a google drive pix share, I can't even easily copy the pix & upload them for you. I'd have to save each of them to my computer, save them to my photobucket acct & then post them individually.

The problem is going to be confirming that there is no other associated damage to other interior structure w/out removing the foam. Which as you can imagine is going to be a difficult. I'd get the trailer up on jack stands & secured so you can get under it on a mechanics dolly & carefully inspect EVERY thru rivet below the water line. Some of the SC tin hulls that have extensive cracking of interior structure have very small hairline cracks in the hull. These are often extremely hard to find and are often only apparent after the hull gets gutted, flipped & completely stripped of all paint on it's exterior.

Once a crack starts to develop in the hull at a rivet thru hole, the cracks will continue migrate until they are drill stopped at the end. Is there any water in the bilge at the end of the day?

What in the heck happened to this Princecraft either before you got it or after to cause all the ribs/bulkheads to crack? At or near max payload weight & pounding thru surf at WOT? I'm not familiar w/ Princecraft boats, but is there any history of poor build quality in the mid-90's?

BlueFin's build may be the most relevant build w/ similar problems:
[h=1]My First StarCraft; 1975 18' SuperSport[/h]

He's been extremely thorough & detailed in both the problems & the repairs.

Good luck w/ your project & welcome to the iboats dry dock.

 

[jigngrub]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

Those cross members aren't really that serious, they're support members for your decking. They hold your deck up around the edges and the little knee wall for your storage compartment. They aren't structural members for your hull, just a little extra support for the edges of your deck and "nailers" for that compartment wall.

I wouldn't bother with welding them, instead I'd remove them and make new ones out of aluminum channel (what they're made of now) or angle and rivet them back in. You could fabricate some clips out of angle to help hold them and give better support.

 

[jbcurt00]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

Those cross members aren't really that serious, they're support members for your decking. They hold your deck up around the edges and the little knee wall for your storage compartment. They aren't structural members for your hull, just a little extra support for the edges of your deck and "nailers" for that compartment wall.

I wouldn't bother with welding them, instead I'd remove them and make new ones out of aluminum channel (what they're made of now) or angle and rivet them back in. You could fabricate some clips out of angle to help hold them and give better support.

Great ^^^, I'd much rather be wrong.

 

[jigngrub]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

Could you post pics with a different method, I tried to copy those so I could mark them up in my paint program to show you what I'm talking about but couldn't copy.

The weight of the water in your livewell is what broke these members, and when you fix it I recommend you add more of them and make them stronger. It'll be a pretty easy fix and not that big of a deal. A bag of rivets and a few pieces of angle and you'll be better than new.

 

[nilaszewski]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

Sorry about the photos, I was having all the same issues with uploading and coping as mentioned above. Think I got that sorted, these should work better. I really appreciate the advice I have already received, and am looking forward to getting this fixed and back on the water.

 

[nilaszewski]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

 

[nilaszewski]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

Thinking about the weight of the water in the live well that makes sense. I liked the interior layout of the boat because we rarely put mor than the drivers seat in. Just boat cushions around the side and sit on the compartments. I don't crash waves because it's hard on my body, my passengers bodies, and the boat.

I do suspect however the previous owner probably liked this boat for the same reasons as myself. Could he have pounded the heck out of it with people sitting on the side compartment? I'm sure he did. I'm going to get a look at the 4th bulkhead in the front in that storage compartment tonight to see if it's also broke, guessing it is so I'll take care of them all at once. I appreciate the advice on how to reinforce this while still being cost effective. I had a few leaky rivets that I drilled out, gooped full of 5200 and then replace with closed end alu pop rivets, strongest tensile I could find. Problem was I had to buy from grainger a box of 250. So to that end, I have TONS of rivets to use!!!


The drivers side isn't really conducive to siting, purely storage with the controls and gunnel so I'm not at all worried about those supports.

 

[jbcurt00]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

This pix was really the primary concern I had about stuff moving. Even the longitudinal stringer's cracked. That suggested more then a little movement. But it too may only be a deck support member & not a stringer.

I'd much rather be wrong & as J&G suggest's it be mostly deck support & not a major problem.

 

[jigngrub]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

To repair your broken cross members use 1-1/2" aluminum angle 1/16" or 1/8" thick. Cut 2 clips that will fit inside of your channel cross members underneath:




When they cut the 2 legs off the channel to lay it over top of the stringers they weakened it and it may as well have been a piece of flay metal instead. They should have cut it to fit inside the stringers and used the angle clips to hold it up to begin with, much stronger.

Since you have the weight of the water in the livewell in that area I'd add at least 3 more cross members made out of the same angle you use for the clips for extra support:

You'll be better than new and won't have to worry about another failure.

You'll have to cut and dig out a little foam in each repair area, but that shouldn't be a problem.

 

[jigngrub]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

Even the longitudinal stringer's cracked. That suggested more then a little movement. But it too may only be a deck support member & not a stringer.

I think that's just a butt joint for 2 pieces of stringer to make a turn with the contour of the hull... or they just slopped 2 pieces in instead of a single piece.

 

[nilaszewski]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

Does this seem reasonable for Alu angle?

1/8" {A** x 1-1/2" {B** x 1-1/2" {C** Angle 6061-T6 Aluminum, Extruded - 6' = $10.29

 

[jigngrub]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

Does this seem reasonable for Alu angle?

1/8" {A** x 1-1/2" {B** x 1-1/2" {C** Angle 6061-T6 Aluminum, Extruded - 6' = $10.29

That's not bad for new angle and a pretty cheap fix too eh?!

 

[nilaszewski]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

Got the braces out tonight. Got the aluminum angle, seems super sturdy, more sturdy than the aluminum that was in the boat. Removed the front compartment floor to expose the 4th brace and it was also broke. So 4 braces plus add 3 more means 7 braces or 14 brackets. Got th all cut up, will take a
Bunch of tinkering tomorrow as the center stringer isn't square. The vertical edge comes out at an angle. Gonna have to bend them all individually to fit. Found an existing angle but the rivets were rattled loose so I drilled and put new in. Can see how the center is on an angle.

 

[nilaszewski]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

 

[jigngrub]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

Looks like you're right on top of it and looking good NZ!

Sitting on those storage tops wasn't the best thing to do, especially over the livewell... but who knew they were fabricated/supported so flimsily?

Your fix will be a good strong one and when you're finished you should be able to sit Rosie O'Donnel and her evil twin on top of that livewell and it won't budge.:laugh:

 

[greenbush future]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

I'm really surprised that this failed as it did, must have been some very heavy folks sitting on top of a full live well, combined with rough water and pounding action. How does the exterior of the boat look where this occurred? Any evidence or bulges ? The fix looks better than factory, which I would be sharing pictures too, just for kicks I guess. I wonder if they have seen this before, not that they would ever admit it. It seems like it might not be the best design, or perhaps the abuse was extreme. Beef her up as you are and if your hull isn't distorted you will be good to go, better than new IMO.

 

[nilaszewski]

Re: Aluminum Bulkhead Stringes not sure really broke please help! thanks!!!

Yea it's a 1995 and I'm the 3rd owner. Bought from and old guy that couldn't even get into the boat anymore. Said he bought it from his friend, guessing that "friend" beat it up a little. In 1995 princecraft offered a lifetime warranty on the hull, I mentioned it to the dealer in passing last year and he said it's not lifetime anymore as a different company owns princecraft now. He said anything built before the current ownership is pretty much SOL... Wasn't expecting a free repair anyway. I was curious because I had a few leaky rivets so that's why I had asked. Didn't feel like pulling the while floor to re buck them. Ended up drilling out and replacing with the same closed end pop rivets that I'm using on this project, sealed with 5200. Worked like a charm. Who needs a warranty. These additional supports and angle braces to fix the current problem is just another example of how the information found on this forum is priceless.