Looking for advice on boat problem

[Texas Proud]

OK, I know there are a good number of engineers out there that might be able to give me some help... but first, I will just put down the problem and see what recommendations are made...


I have an 18 ft runabout boat... here is a pic of somebody's boat... it was easier to steal a pic than get one of my own (BTW, this is my color!!)

So, if you look at the back sun deck, it is held by two hinges on each side... You can see the one on the left pretty good on the pic... there are also two lifts to help you lift it up.. all pretty nice...

My problem is that 4 of the 6 screws that hold the hinges to the wood deck that 'meat' of the deck have 'ripped' out!!!

So on the right side the hinge is not attached to anything... on the left there are still two screws...

NOW, the screws are not really wood screws from the knowledge that I have.... they look like this... ( I can get a pic of them if needed, below is one that kinda looks like it).. they literally ripped out of the deck... I have a hole where they used to be... so no wood for them to grab hold of....

So, call the manufacturer and they say 'you need to replace the deck'.... well, a new deck cost $2500 and that is just the part... I could easily replace it myself with some help to move it around...

Went to a boat repair place today and they said 'you need to go to so and so shop'... they do fiberglass and he thought they could fix it.... called them and he said 'you will have to replace the board in the deck, but I do not do it'... I got a name of a place that does boat upholstery... will call tomorrow, but I am thinking that they will charge in the $600 to $1000 range....


ANY SUGGESTIONS on what can be done to 'fix' the problem As I said, I will give my thought after reading some.... I do not want to

Break Out Another Thousand....

 

[Dalez]

I'm not an engineer but I would take the sundeck off and fill the holes with some sort of epoxy and after it cures drill some pilot holes then reinstall some screws. I can't imagine having to replace it.

 

[travelover]

If the wood is rotted, you can dry it out and use a diluted resin product like GitRot to firm it up. Then redrill it for a screw. That bolt looks like it originally threaded into a special type of T nut, which may have pulled out of the wood.

 

[Koolau]

i'm guessing a good body shop could fix the whole thing for you. For DIY, could you use the type of bolts that expand once inserted - something like you would use in a dry-wall application (see some pictures here)?

https://images.search.yahoo.com/sea...wMxBHZ0aWQDBHNlYwNzYw--?p="bolts+For+Drywall"

 

[Souschef]

The screw you show is a hex head machine bolt. As travelover has said, that has to be threaded into a nut of some sort,which may have pulled out
A T-nut, T nut, or tee nut (also known as a blind nut, which can however also refer to a rivet nut or an insert nut) is a type of nut used to fasten a wood, particle or composite materials workpiece, leaving a flush surface. It has a long, thin body and a flange at one end, resembling a T in profile.

 

[pb4uski]

If it is similar to my (former) bowrider, the back deck is basically a piece of marine plywood with padding and upholstery on top and bottom of it... right? And I assume that the reason that the bolts are not biting is that the plywood has rotted? From the bolt you included I assume that there are some threaded nipples attached to the plywood (see examples below) that the bolts go into and perhaps those are no longer getting a good bite into the plywood and are turning.

If so, one option would be to take it all apart, use the old plywood as a template to cut a new piece of marine plywood and reassemble with new parts.

Another option if the rotting is just where the hinges are might be to move the hinges a few inches towards the middle on each side and they will hopefully get better bite. Or leave them where they are and use suitably sized carriage bolts that go right through the whole deck... and paint the tops of the carriage bolts to match the color of the upholstery or use brass carriage bolts. Or instead of carriage bolts you might use furniture fasteners for a cleaner look (last picture).

 

[Bamaman]

Advice you received sounds like expensive overkill. Boat dealers and service departments often take advantage of unknowing customers @ $110 per labor hour. It's not really clear where the bolts go through, but I'll address it a little bit.

I too believe an epoxy putty could fill the holes to where the bolts wouldn't wobble. You may need longer bolts. You might also use epoxy to "glue" a plywood backing to the fiberglass where you can re-drill holes to hold down the hinges. It may take longer stainless steel bolts too.

You don't say where you're located. If you have a West Marine retail store around, they carry all the supplies to do most marine hull maintenance. The guys there may can tell you how to fix it too.

With a little ingenuity, this should be do-able.

 

[Texas Proud]

Thanks for the quick responses....

There did not seem to be any type of nut... I guess I will have to take the cover off and check... but, I did take out the two bolts holding the hydraulic lift and they were wiggling around and I did not see any nut... that is what is so strange...

I cannot use longer bolts as they would probably go thru...

Also, I will check, but from what I saw the wood was not rotted... heck, the boat is not used much and is in my garage... I just passed 180 hours on it and it is 11 years old...

The epoxy is a possibility.... another thing I was thinking was to use some kind of glue (maybe epoxy) to just glue the hinge on the deck... why worry about screws. I just do not know if this will hold..

 

[38Chevy454]

Take some close-up pics of the hinge mounting and the board they mount into. Then we can suggest a better fix.

The bolt you showed is machine thread and will not hold in wood, it has to thread into metal of some type.

......Or instead of carriage bolts you might use furniture fasteners for a cleaner look (last picture).

When I was a kid and worked in a shop, we called those sex bolts, hahaha.

 

[pb4uski]

If the fasteners are bolts and not screws, which the picture in your OP suggests, then thee has to be some threaded part that the bolts screw into... as you know a bolt doesn't screw into wood... but you may have to take the cover off to get a good look at them.

If they threaded part is just loose and the wood isn't rotted then you might be able to epoxy the threaded parts to the wood.

I don't think epoxying the hinge to the deck will work... the stresses are such that you need a fastener.

One of my suggestions, a suitably sized carriage bolt and nut would go all the way through the wood... the round end would be visible from outside...a bit redneck of a solution perhaps... but easy to do and IMO much better than spending $600 to $2,500 on an 11 year old boat.

 

[Dalez]

I also had a Stingray like the one pictured which I recently sold, so I cant look at it but I thought it had a piano hinge the whole length of the sundeck. So that is a possibility for you to get some more bite on the wood.

 

[FIREmenow]

After reading all the replies, the first step I would do is peel back the upholstery and see what is going on.

I have been working on boats for 30 years - fiberglass, wood, epoxy resin, power, sailboats, and trawlers - you name it. I do have a mantra when working on boats, "Do it right, or do it twice!", so my opinions might be skewed.

Epoxy alone will not do much, especially if the surrounding structure is compromised. You need some fiberglass or other mechanical structure to build up the overall "system". Especially if wet or dirty wood is involved - any epoxy will just fall out over time.

If, as you say, it has been in dry storage most of its life, it probably is not wet or rotted wood that is the problem.

As others have said, the original bolt needs to, and likely was, threaded into something mechanical. Sometimes boat manufacturer's embed the nut-end of the system right into fiberglass, similar to a t-nut in wood.

If it is a wood (only) deck, my "small area" fix would be to remove any damaged area of wood, grind down or "dish-out" the area of the wood where the hinge is, and then laminate many layers of fiberglass to the dished out area of the wood (large bonding area) until it is built up to the original surface level. You could then use regular screws into the fiberglass (may only last another 10 years), or through-bolt with stainless t-nuts or threaded inserts epoxied into the fiberglass.

Again, I would pull back the upholstery and see what is going on for sure. Who knows? Maybe there is a t-nut or similar under there that just backed off of the bolt and is running around loose! Take some pictures and post them here when you do.

 

[kitesurfer2]

cut out the bad and fill in with west system epoxy...use a few layers of cloth....a backing plate...stainless steel threaded insert ...

it's not hard, but may be time consuming.

 

[rayinpenn]

You've gotten some great advice here but no one of them has gotten to the root cause: You own a boat.


Sent from my iPad using Early Retirement Forumh

 

[CRLLS]

First determine if the wood is rotten. If that is so, replace the entire sheet. You can use the old piece of wood as a template and re-use the foam and vinyl. Use stainless staples to re-fit the vinyl. If you need to attach stiffeners, make new ones from treated wood. As said earlier, do it once and forget it. Just did this same thing on my "new-to-me" boat.

If the wood is otherwise in good condition. Make up 2 steel plates larger than the area of the hinge with many holes. Drill and tap holes for the hinge ( or use weld nuts ) and 8 or more holes for wood screws to screw the plate to new areas in the wood. You can paint it very well or have the plate powder coated to prevent rust. Better, you can make it out of Stainless Steel. Once done, the hinge is secured to the plate and the plate has many more screws into the marine ply, making it very secure from thread pull-out.

But I suspect you will find the wood is rotten.

 

[ERD50]

I agree with others that you really need to get it apart somewhat, to better understand the problem. The solution really depends on what you've got to work with.

If it turns out like this, I think the metal plate backing suggested by CRLLS is a very good solution, distributes those stresses over a much larger area:

... If the wood is otherwise in good condition. Make up 2 steel plates larger than the area of the hinge with many holes. Drill and tap holes for the hinge ( or use weld nuts ) and 8 or more holes for wood screws to screw the plate to new areas in the wood. You can paint it very well or have the plate powder coated to prevent rust. Better, you can make it out of Stainless Steel. Once done, the hinge is secured to the plate and the plate has many more screws into the marine ply, making it very secure from thread pull-out. ...

But if the plate gets clamped by the hinge bolts, I'm not sure you need any other screws in the plate. The hings bolts should keep everything from moving? Again, depends on what you find though.

-ERD50

 

[eytonxav]

Maybe also consider adding another hinge in the middle, in addition to what Firemenow and kitesurfer2 said.

 

[Sunset]

....
One of my suggestions, a suitably sized carriage bolt and nut would go all the way through the wood... the round end would be visible from outside...a bit redneck of a solution perhaps... but easy to do and IMO much better than spending $600 to $2,500 on an 11 year old boat.

As long as he used stainless steel bolts and nut and washers it would be matching perfectly to all the shiny chome/steel already showing in the photo.

Not too red-neck at all...

 

[FIREmenow]

As long as he used stainless steel bolts and nut and washers it would be matching perfectly to all the shiny chome/steel already showing in the photo.

Not too red-neck at all...

If you are talking about coming all the way up through the upholstery, I would worry (a lot) about water intrusion.....

 

[pb4uski]

True, but if you apply silicone liberally to the hole and underside of the carriage bolt before bolting that should mitigate water intrusion.

Admittedly a less than ideal solution. A more elegant solution would be to take it apart and (assuming some sort of rotting that is preventing the threaded piece from biting) replace the plywood, bolt the hinge to the plywood deck and then reinstall the upholstery with SS staples. That would provide a secure attachment of the hinges and avoid the water intrusion potential of the through the upholstery solution.

 

[FIREmenow]

True, but if you apply silicone liberally to the hole and underside of the carriage bolt before bolting that should mitigate water intrusion.

......for about 3 months.

 

[CRLLS]

My idea was to screw the plate to the underside of the deck. Not to clamp the wood between the plate and the hinge. This would not require removing the foam or vinyl. The hinge do provide essentially a point load that could be the only problem. This distributes the load across a larger area and thru multiple screws into the wood. If the plan is to clamp the wood between the hinge and the plate, then the plate only needs to be slightly larger than the hinge itself. But there is already a problem in this area. This is why I suggested the flush plate.

I hope this makes sense.

I agree with others that you really need to get it apart somewhat, to better understand the problem. The solution really depends on what you've got to work with.

If it turns out like this, I think the metal plate backing suggested by CRLLS is a very good solution, distributes those stresses over a much larger area:



But if the plate gets clamped by the hinge bolts, I'm not sure you need any other screws in the plate. The hings bolts should keep everything from moving? Again, depends on what you find though.

-ERD50

 

[pb4uski]

......for about 3 months.

I dunno about that... it is a common solution for roof penetrations (like antenna mounts) and IME seldom a problem.... and roofs get a lot more water than a boat that is garaged.

 

[FIREmenow]

I dunno about that... it is a common solution for roof penetrations (like antenna mounts) and IME seldom a problem.

Roofs don't pound through waves at 20mph, flexing the entire way, or have dirty, mildew-ey, soft vinyl as a substrate.

Believe me, I have re-worked enough silicone "fixed" repairs on OPB (other peoples boats) to know. Never-mind the fact that once you put silicone on a surface, NOTHING else will ever adhere there well.

Silicone has its place/uses, for sure. However, irrespective of the fact that everyone uses it, silicone is a HUGE no-no on (well-found) boats. Telltales could certainly be all of the wood rot problems on all of the low-end manufacturer's boats after a inordinately short time.

No silicone EVER on my boats.

 

[pb4uski]

Ok, we agree to disagree.