Looking for advice on boat problem

[Sunset]

Glad to hear of the update. May not be all that hard to fix after all since you are about 1/3 of the way done already.

 

[HFWR]

Seems like a large area for 1/2" plywood...

 

[NW-Bound]

I do not know much about boats, but machine bolts threading into plywood is pretty bizarre. And 1/2 plywood is really thin without reinforcement at the hinges, no matter what fasteners one uses. I would not be comfortable with just the inserts as shown in previous posts, but they did not even use those. Holy moly! I would feel OK with a piano hinge though, along with many fasteners, as it distributes the load over the whole width.

 

[Texas Proud]

I do not know much about boats, but machine bolts threading into plywood is pretty bizarre. And 1/2 plywood is really thin without reinforcement at the hinges, no matter what fasteners one uses. I would not be comfortable with just the inserts as shown in previous posts, but they did not even use those. Holy moly! I would feel OK with a piano hinge though, along with many fasteners, as it distributes the load over the whole width.

Yea, it is not a great design... but a piano hinge is not an option without some modifications at the hinges are recessed along where the piano hinge would go... I think if I installed one it would raise the deck up just a bit... but thinking about it, I do not have to go the whole length and who cares if it is 1/4 inch raised.... might be an option if the other does not work...

Also, I do think it is a bit strange to have 1/2 inch plywood... but it is padded, so the whole thing is about an inch thick... but, we walk on it and lay on it when we are out on the lake... seems to be strong as we have had 3 adults and a 12yo kid on it at the same time....

 

[NW-Bound]

The plywood might be OK for the load, but not at the attachment point where the bolts are threaded into it. I would not cut a thread into even 1/2" solid oak and expect it to hold a machine bolt.

If there's a metal backing to the other side of plywood, then I would feel more comfortable than just the threaded inserts.

 

[CRLLS]

I don't have pics but just rebuilt a similar area on my boat about a month ago, full width of the boat but only about 16 or so inches front to back. The wood on my boat was being held together by the foam and vinyl! It was, and is now again, made of marine ply. Mine is held on by an aluminum piano hinge, about 2/3rds the width of the boat. Many stainless wood screws into the ply. Mine is a 27 yr old boat. If I get another 5-10 yrs from this, I will be happy.

Like I mentioned in post #15, I would get a couple of plates of aluminum (suggested steel earlier) , say 8 inches square by ~3/16"" thick and screw them to the "good" wood with about 12 stainless wood screws. Then screw the hinges to tapped holes in the aluminum plates and be done (for a while). There is no way to keep this from occurring again. It is inherent in the design. I think that wood and boat should never be used in the same sentence. But...... you have to work with what is given.

 

[Texas Proud]

I think the easiest solution would be to get SS or brass wood screws as large in diameter as will fit through the hinge and as long as you can given the thickness of the deck material and the hinge... hopefully those will bite into the decking material enough to do the trick. If the hole is rounded out and too loose you can stuff the hole with some folded toothpicks to provide more bite.

Alternatively you could get some fasteners that fit your bolts like the piece on the right in the attached picture and install those into the wood (looks like they install with an hex wrench) and hopefully that should work.

OK... finally got around to trying this out...


And... I do not think the wood is strong enough to hold them....

They are getting a bite, but I can hear the wood and it seems like it not solid... They are holding without any stress, but not sure how strong it is... I think I will try some glue and see if that helps...

Any suggestions on glue.... this is metal to steel... I have not tried it but have read here good reviews of Gorilla Glue....

 

[ERD50]

OK... finally got around to trying this out...


And... I do not think the wood is strong enough to hold them....

They are getting a bite, but I can hear the wood and it seems like it not solid... They are holding without any stress, but not sure how strong it is... I think I will try some glue and see if that helps...

Any suggestions on glue.... this is metal to steel... I have not tried it but have read here good reviews of Gorilla Glue....

I doubt that any glue is going to help much. If the inserts seem marginal though, maybe filling with epoxy (JB Weld) while you insert them. You will either need to fill the threads with wax or something to keep them clear of epoxy, or just add the bolts and let the whole thing be epoxied together, but you'll probably need to cut the bolts to get it apart if needed.

I would not use Gorilla Glue.

I really think you are better off with the earlier suggestions - add a larger plate so you can add many screws and spread the forces around, that will also support the wood. Attach the hinges to that plate, maybe add more hinges to spread forces even more. I'd try to get through to the other side if that's not too hard, but a plate screwed to the one side could do it. You could epoxy that as well, for added spread of the forces.

-ERD50

 

[travelover]

Back in post #3, I recommended GitRot, a diluted resin. If the plywood is rotten or de-laminated, this stuff soaks in and hardens to give it back most of the original strength.

 

[pb4uski]

Off topic, but this afternoon I used a product to rid my pontoon boat seats of mildew that was positively amazing. The product is called Marine 31 Mildew Remover. Spray it on, let it sit about 3 minutes and it essentially dissolves the mildew and you wipe it off, rinse with water and dry.

While it has a slight bleach smell, I think it is more bleachy than it seems as some overspray got on my colored t-shirt and it now has white spots. After I was done I rinsed everything well with water.

Before and after pictures below.

I plan to order more so I'll have some on hand. $18 for a 20 oz bottle that did my 20' pontoon with a little left over. The also have a mildew guard product that I may try , but that is more expensive ($30 for 20 oz). But very reasonable compared to the cost of reupholstering.

 

[ERD50]

Off topic, but this afternoon I used a product to rid my pontoon boat seats of mildew that was positively amazing. ...
While it has a slight bleach smell, I think it is more bleachy than it seems as some overspray got on my colored t-shirt and it now has white spots. After I was done I rinsed everything well with water. ...

Did you try a plain diluted bleach spray? Bleach removes mildew amazingly fast, and amazingly cheap.

-ERD50

 

[Sunset]

Your pontoon boat cleaned up very nicely.
I also was wondering if you tried a weak solution of bleach before this product ?

 

[pb4uski]

I did ... a few months ago... and it didn't seem to work well. This product literally melted the mildew away.

 

[Texas Proud]

I think the easiest solution would be to get SS or brass wood screws as large in diameter as will fit through the hinge and as long as you can given the thickness of the deck material and the hinge... hopefully those will bite into the decking material enough to do the trick. If the hole is rounded out and too loose you can stuff the hole with some folded toothpicks to provide more bite.

Alternatively you could get some fasteners that fit your bolts like the piece on the right in the attached picture and install those into the wood (looks like they install with an hex wrench) and hopefully that should work.

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.

Thought you guys who gave suggestions would like an update....


OK... finally got around to doing what I needed. Got GitRot, but they say you should use it when outside temp is below 70... well, that is NOT anytime in the summer or fall around here...

Also bought some syringes so I could put the GitRot in the holes easier... I did have a problem in that the holes in the wood were all the way through... tried to plug them, but the GitRot would still get around... drilled 3 holes 3/4 of the way through the wood around each hole.... for a total of 9 for each hinge...

Just to let people know... GitRot works GREAT... I would fill the hole and even put more on top... come back the next day and it is all gone!!! Do it again and again it is all gone... I think I had to put GitRot in 4 or 5 times until the wood stopped soaking it up... Now the wood is really hard...


Bought the inserts that pb4uski suggested... so this morning drilled the holes in the GitRot and screwed them in.... Now, I was starting to drill where the lifters were screwed in and guess what THEY HAD INSERTS THERE!!!! They were deep in the hole, but I saw metal coming out and looked down inside and there were inserts.... where were the ones down where the hinges were located

But, the inserts went in and 5 of 6 were pretty strong.... one seemed to be holding well, but not great... Had the family help lift it up and screwed everything together....


So far, it is working great.... seems to be holding pretty strongly... as long as I get 5 to 7 years out of it I will be happy...


THANKS TO ALL FOR THE SUGGESTIONS.... this was one that I did not know at all... and seemed like the easiest to do...




BTW, there is a 'bump' you can feel under the pad on one of the locations... the GitRot was leaking as I said and pooled below and formed a cover on the wood... no big deal.... if you did not know I had put all this GitRot there you would just think it was something to do with the padding...

 

[travelover]

Awesome. Glad it worked out for you.

 

[Sunset]

Thanks for the update, always nice to know the ending.

 

[ArkTinkerer]

May be a little late for you but when I use inserts like that I usually coat them with adhesive (usually epoxy) before inserting. Makes them much more solid and less likely to back out. Oh, and wipe or wash them with acetone or alcohol first to get rid of any oil or mold release that would prevent the glue from adhering.

 

[Texas Proud]

May be a little late for you but when I use inserts like that I usually coat them with adhesive (usually epoxy) before inserting. Makes them much more solid and less likely to back out. Oh, and wipe or wash them with acetone or alcohol first to get rid of any oil or mold release that would prevent the glue from adhering.

Thanks for the advice... I had thought about that just a bit, but did not do it....

However, since it seemed to work so well, if something happens to what I have now I will redo and do the epoxy add on... hopefully what I have done will be enough until I get rid of the boat...