Fixing hull warp

Hi all --sorta new here first post but been lurking for a while.


I got offered a boat a few days ago. Well...a project boat. Its a 16' outboard that's had the transom, stringers,foam and deck replaced. The owner--who is a neighbor has had the boat sitting under his carport for the past 2 years. The trailer its on has missing keel rollers.


He told me that he plans to haul it to the junkyard. When I asked why he said that when he was fixing it --and had the cap off --the hull warped. Now the cap wont fit back on ---its about 3" port/starboard too small. Instead of a shoebox fit the cap --along the sides---rests on top of the hull.


I hate to see the boat carted to the junkyard--- is there a way to fix this?

Re: Fixing hull warp

Yes but it involves full demolition. Problem is he did not support the hull with a cradle or take measurements while he did the work. You would need to support the hull, pull the cap and redo everything

Re: Fixing hull warp

matt167 said:

Yes but it involves full demolition. Problem is he did not support the hull with a cradle or take measurements while he did the work. You would need to support the hull, pull the cap and redo everything

Click to expand...

No -- cap is still off. The sides are the issue. The bottom of the hull is straight--the hull sides bow out a bit. I was hoping to somehow force them into place and then rivet the cap back on. Or, cut a section of the cap off and reglass a piece to make it whole again.

Re: Fixing hull warp

The whole hull has to be crookid for the cap not to fit. Cap should take a little bit of finesse to fit back on, but if it takes a ton, then something's out of wack. You can try to make the cap fit, but the boat may never sit right in the water... You can take measurements from the deck to the top in 4-6 places and see if they are all equal side to side. If they are, you might be lucky, but I suspect the problem is below deck.

Re: Fixing hull warp

Unfortunately this occurs quite a bit. You can try to torque the hull back into shape using nylon straps but there's not guarantees. Pics of the boat with the cap sitting in place would help us to help you

Re: Fixing hull warp

Measuring from the deck to where the cap should be is the same all around. The distance from the centerline to port and starboard is different. The port side is different by 2".

Im thinking that the sides just bowed out and the bottom is ok. The extra 2" is just along a section about 4' long.



Thanks for the replies.

Re: Fixing hull warp

I doubt the hull "relaxed" that much.. it was probably a PITA for the builder to get that deck to fit.

You just have to find a way to Fit it back on ..

YD.

Re: Fixing hull warp

The sides of the hull sagged away from centerline when the cap was removed, and then bellied somehow. It may have settled w/ or w/out distorting the bottom of the hull. The cap will still fit over the tip of the bow & the back of the transom? It's just side to side that won't allow the cap to drop over? Like the shoebox you mentioned earlier?

WOG nailed it asking for pix. That would help, esp if you can SEE the distortion. It'd also help by showing that it's a semi-vee, deep vee or tri-hull.

If the centerline to port dimension is 2" different then the starboard, clearly something moved & when they failed to notice your neighbor glassed it that way. It may be very difficult to judge w/ the boat on a trailer, but if the hull sides moved that much, I'd be very surprised that there was NO movement of the bottom of the hull.

Pix of the hull bottom would be helpful too.

The bottom of the hull could develop hook or twist that could alter the boats performance, possibly to the point of being unsafe at planing speed.

The pix of the 'new' to you project won't be that different from MANY of the early pix in MOST of the resto threads. They all SCREAM: 'What was he thinking' to most people, the Admiral in your life chief among them (it's the wife/significant other/etc).

But we're an odd lot & love looking at debris filled wrecks & 'seeing' the possibilities :watermelon:

Welcome to the iboats dry dock

Re: Fixing hull warp

The sides of the hull sagged away from centerline when the cap was removed, and then bellied somehow. It may have settled w/ or w/out distorting the bottom of the hull. The cap will still fit over the tip of the bow & the back of the transom? It's just side to side that won't allow the cap to drop over? Like the shoebox you mentioned earlier?

Click to expand...

This is exactly correct. Ive measured the bottom --corner to corner, side to side and the only way it could be warped is when the bow angles upward. The planning surface is flat

Its a trihull side console---and I have no way of posting pics.


The way I see it is I have a few options:

1) Let the owner haul it to the dump

2) Force the sides together and then rivet the cap back on ---which would cause significant stress and might pull the rivits right back out.

3) Cut the cap:

a) Down the centerline and then rivet to the hull and glass in the bit at the stern that was cut.

b) Cut a section of the side off --fit the cap --and then glass and rivet the section back to the cap.

4) Some combo of cutting off the rear of the cap and leaving it an open floorplan in the rear keeping the side console.

Re: Fixing hull warp

The 'best' solution, IMHO, would be to remove the most likely incorrectly installed deck (if it's asymmetrical, it can't be 'correct', right?) and install the cap. The flotation foam will probably need to come out too. It likely is cured in the asymmetrical shape.

Then do your best to support the hull sides & hull bottom.

Make sure everything is again symetrical, everything below deck is ready to be decked over (didn't get the hull & deck 'correct', maybe didn't get everything below deck right either, transom cored too) and install the deck.

All the other courses of action you posted don't address the fundamental asymmetrical differences. That's not correct, or good. And stresses the hull in ways the designer didn't intend. It's hard to 'see' how a 2" difference didn't manifest itself in the hull in other ways. Perhaps it's only bellied from the bottom of the outer keel upward & out.

However, the belly pulled the bow back................

W/out pix, IMHO, you will be hard pressed to get good to go recommendations of not addressing the asymmetrical condition.

Re: Fixing hull warp

Boats dont shrink like that .. they dont move that much.

I think you might have a cap thats not made for the hull.

3" on each side for varient is kinda large IMHO ..

YD.

Re: Fixing hull warp

I think JBcurt is onto the real issue. Let me see if I can explain it in a another way.

The sides are supported by the cap when the PO removed the cap the side then can bow out. Since the boat was sitting on a trailer with rollers there was not proper support nor was there support to the sides so every time the PO climbed in the boat he created a bigger bow which would release when his weight was removed. Now when he installed the sole (or deck or floor whatever you want to call it) he installed it at the measurements with the sides bowed out. The hull can be symmetrical but unless you pull up the sole you wont be able to fix the issue since it is pushing the sides out. Even a 1/2" extra on that section of the side by the time you get to the rail can manifest itself in a 3" gap. Forcing it back would put stress on the fiberglass at the sole to side joint and could cause it to crack and/or break at that point allowing a point for water intrusion below the waterline of the hull. You can most likely save most of the work already done by the PO if you want or since he didn't do this right I would pull it all up. A hull on rollers that has had the stringers, sole and transom all replaced has a strong possibility of a hook being put in the hull which can cause uncontrollable porpoising of the hull or unknown reactions while under power. The only way to tell on this is to put a straight edge over the entire bottom side of the hull with it off the trailer if you can.

Is this boat trashed no its not as I know its repairable. If you want to get the sides back in the best down and dirty way is to mark on the hull where the cap doesn't match up front and back, transfer those marks to the sole and extend them out about 12", cut the tabbing of the sole to the hull surgically the entire length (including the extra 12" to each end) to separate the hull from the sole along those lines. Then in the center of each section measure 1/2" into the sole then figure out either a straight line or gentle curve from the cut edge to the center 1/2" indent and back out the other cut edge. Cut this section out along this line then see if the sides will flex back up to the sole to close the gap if they do then try put the cap back on. If it now fits then glass everything up and be on your way. Still check for hooks in the hull though to be safe. These can be fixed with a lot of work from the outside if you want but its messy and tiring work on your back.

Re: Fixing hull warp

You've got nothing in it but some time, attach the ratchet straps and start cranking, then put the cap on. Run some screws through both halves then rivet them together or just use the screws. There might be some stress there but I think as it is spread over several fasteners it will eventually cooperate. I would imagine that 9 times out of 10, there are some issues when replacing the cap after a full rebuild. I know that I had them probably more than an inch off.

After re-installing the cap, it will more than be longer than the hull I imagine, you can always seal that gap. If it floats and gets on plane/moves as it should, who cares it the cap fits.

Other hand, you crank and you break the boat hull or it doesn't perform as it should, you have a great place to start in the repair. Pull the cap, cut out the deck, re-support the hull and re-deck; try again. Still relatively little investment for something to get out on the water with.

After seeing the guts of a boat, I doubt that anything was done perfectly, we would hope/imagine that would be the case but it definitely isn't. There was just some guy building the thing with probably a lot less interest in doing an outstanding job than you. Get at it!

Re: Fixing hull warp

I have worked on smaller boats that are in production ( without stringers/bulkies ) and have Never found a problem such as described.

In production ( right off the lam rack ) they go to the stringer installs. The hulls are carried from point to point for inspection and rigging with simple carts. There is little deflection in the hull itself.

They still rig the wiring and pipes without that much deflection..

I still think this is a cap that has gone haywire somehow that is not being discussed ..If its a true fitted cap..

YD.

Re: Fixing hull warp

The cap may be also 'racked' in someway, but how'd the hull become asymmetrical if it wasn't due to being unsupported during cap removal, demo &/or put back?

The put back was careless/inaccurate? Maybe, but that wasn't the primary cause on other projects, or at least it didn't seem that way. Once better supported, and w/ the cap in place, most have resolved w/ well done & sound decks and caps that fit.

Unless the 2" variance is also in error.....

Admittedly my 1960 FireFlite has a flimsy hull, but it immediately gives way during cap removal if it's un-supported (it was on the trailer, but that's not enough support) prior to cap removal. Quite a significant amount, probably more then 2" wider per side from the boats centerline. The hull sides sag 'open', which deflects the bottom of the hull, and 'pulls' the bow aft, towards the stern. The transom was not yet fully cut free, so I don't know if would have been impacted.

It was 1 of 2 extremely unpleasant early consequences of actions done in haste.

Regardless, the OP wasn't the one that did any of the work to date on this project, so it's all speculative. It could be any or all of the 3: hull, cap, deck.

Anyway to improve the cap fitment w/out cutting the cap into quarters & stretching it thru both axis? Or finding the misplaced/discarded original cap?

Should the OP leave the clearly incorrectly done deck? Whether the asymmetrical hull works, if that isn't done right, is whatever that was done below done right?

Re: Fixing hull warp

Jb has a point . Is every thing under the deck done right ? I am no expert but how much could the hull really flex ? If you move the hull sides back and forth say 2" how much could it move down at the deck height ... 1/4" maybe 1/2" . If from the center line is 2" off that's really only an inch on both sides . I guess ?
Maybe cut a 3" slot out of the middle of the deck . Re-support the hull till cap fits then patch the deck .
Or go jas on it and haul it to the dump ..

Re: Fixing hull warp

Again .. I suggest that you cant have a cap that shrinks on all sides.

3" variable is .. well .. kinda out of the Norm of things.

YD.

Re: Fixing hull warp

I agree, the cap hasn't shrunk. Since it was under the neighbor's carport for 2years, I kinda doubt that it's not the cap that was previously on this hull.

Willy: Nobody you know has a cellphone w/ a camera that will take a few pix & email them to you? You've got internet service to log on at iboats, even if it's free at the library or on a non-camera smartphone, you can get a free email acct (but don't you need an email address to join iboat's forum?) & a free photobucket acct. W/ those you should be able to post a pix, provided someone has a cell camera.

Best of luck, however you choose to proceed.

Re: Fixing hull warp

Ok guys --been replaceing the hardwear on the trailer so it will sit as the factory intended. Got 3 new keel rollers and all new stainless to go on the galvanized trailer so the boat will sit correctly.

I was able to also turn the hull over so the keel is down and measure much better.

Turns out that the 4x4's it was resting on were distorting the sides--pushing them out of place. The short of it is that the sides are out past the cap --by 1.5" ON BOTH SIDES. Symetrically.


Im hoping that once I set the hull back on the refurbished trailer it will get back into more of a better shape.

If it doesn't I have a plan to move those sides the 1.5' they need to get the cap back on. I will drill holes in the sides and using a piece if 2x4 put in eyehooks that are connected to a turnbuckle to the other side. Then I just start cranking until they are in spec--or they crack. If they crack I will remove the inner glass and foam and make it easier.

Re: Fixing hull warp

Sounds like a plan. Happy cranking!