?? on repairing FG jon boat.

[odleon]

Hello, this is my first post here.
I apologize in advance for the stupid questions.

This is my first boat as well.

I also did hours of reading before i asked this with no definitive answers.

Recently i was given an old 14ft fiberglass jon boat with a bad floor and transom.
Today I removed the inner skin of the transom and the whole floor. Seems like the manufacturer used 1/4" ply for the floor and 1.5" on the transom. After cleaning out all the rotten wood, i noticed the stringers were originally wood enclosed with FG. the wood has completely rotten out and the fg shell remains, only thing, is that they didn't really do a great job on them. the stringers going front to back of the boat are pretty sturdy, but the ones going side to side are weak. I pulled up part of one with my hand.

My questions are these:

Should i remove everything and start over? Or can i add more glass to reinforce the current stringers??

Can i use poly resin to repair this??

Once i get the stringers situated, what can i use to bond the new plywood deck to the stringers?? (if i can keep the current stringers, the would be hollow)

How can i bond the new transom to the outer FG skin??


Thanks in advance for your time.

Omar Leon

 

[ezmobee]

Re: ?? on repairing FG jon boat.

Ok I'm not a glass guy but I'll take a shot with what I do know.

Yes you want to tear everything out and start anew. Poly resin is fine as it's what your boat was built with in the first place. Bonding can be done with PL Premium construction adhesive or thickened poly resin (glass guys will know better the recipe on that). It sounds to me that even though you've got a little boat there, it's built the same as larger ones so start reading any of the glass boat projects here for tips and ideas. (friscoboater's is basically the bible at this point).

 

[odleon]

Re: ?? on repairing FG jon boat.

Here are some pics.

I was thinking, maybe clean up the random loose fibers and then add a layer of FG to strengthen up the stringers.

 

[odleon]

Re: ?? on repairing FG jon boat.

 

[Woodonglass]

Re: ?? on repairing FG jon boat.

Welcome to iBoats!
That is a unique looking boat. I would recommend drilling into the stingers with a drill and checking the shavings. If the wood is dry then great. If it is wet and mushy then you will need to cut and grind em ALL out and start fresh. Transom looks like it needs to be replaced too. It will be a challenge with those side walls. Probably have to cut them away and then glass em back in.

 

[odleon]

Re: ?? on repairing FG jon boat.

The wood in the stringers is completely gone. i was thinking basically using the stringers as a form and just add more glass to them. most of them are actually pretty solid.

the side walls are full of foam. i was dreading that because i expected it to be completely waterlogged, but to my surprise, after cutting out a section to get to the hull to repair a hole, its pretty dry.

I got all the old wood from the transom out. i ended up cutting the cap so i can slide the new wood in place. Can i use PL adhesive to bond the new wood to the FG here??

Thanks

 

[Woodonglass]

Re: ?? on repairing FG jon boat.

Are you saying it is gone because it has completely rotted away, or was it never there? You have to understand that if there was Wood inside of the fiberglass shells it plays an integral part in the overall structural integrity of your boats hull. It MUST be replaced.

 

[odleon]

Re: ?? on repairing FG jon boat.

They have completely rotted out.

The way the manufacturer made the stringers, the ones going front to back are still very sturdy. They fully encased the wood in FG.

The ones going side to side are a different story. The seem very sloppy.Not fully connected to the hull, with a lot of gaps( you can see this in the first pic) I wonder if they added those to hold the main ones in place while they glassed them in??

 

[Woodonglass]

Re: ?? on repairing FG jon boat.

so the LONG ones (Stringers) are Solid, Wood is still good. You have drill into them and verified the wood is solid and NOT wet. But the Side to Side ones (Bulkheads) are all gone, rotted out. If that is the case then you will still need to grind out all of the BAD Glass Re-Fabricate the wood Bulkheads ReGlass them and tab them into the hull in order for your hull to maintain it's structural integrity. It's not as hard as it sound. We will be here to help you through the process. Get a 4 1/2 inch grinder with a back up pad and some 36 grit sanding discs and it will make short work of grinding all that bad glass out. Make sure and wear goggles and a GOOD respirator and long sleeve shirt. It really itches.

 

[Yacht Dr.]

Re: ?? on repairing FG jon boat.

Hello odleon and welcome to Iboats..

You have a chopper gunned boat ..

I think you can just grind/prep across those little stringers and a few layers of 1.5 oz mat and 1708 will make that little thing stronger then from the back yard it was built in.

Let The Core melt to almost nothing..your fine.

Your on the right track .. ( unless you plan on slapping a 150 yamy instead of your what.. 40 ? .. 30 HP ?? ) .

I personally dont bond my deck to my stringers for small boats.. only to the sides ( if needed )

YD.

 

[odleon]

Re: ?? on repairing FG jon boat.

The wood is completely gone.

How many layers of mat do you recommend?? I have plenty of mat, but no local access to 1708.

Should i reinforce just the side to side ones?? they didnt seem to provide much strength to begin with.

Shes only getting a 9.9 Evinrude. Closest lake to me has a 10hp limit.

 

[Yacht Dr.]

Re: ?? on repairing FG jon boat.

Plenty of mat cool .. I say 3-4 layers of 1.5 oz mat should make a good solid stringer system outa that.

I would do the side to sides. New deck..level stringers and mini supports...All should be built up the same..

Pre-cut or Pre-tare your mat strips .. have them All ready to go before you mix your resin.

Dont worry too much about your cris-cross cappings on the first run .. do your main tabbings across lengths.

Start in the bow and work your way back .. Do it in the shade and should take about 1-2 hours to do your main member lams ( nice thing is you can take a break after every batch of resin ).

You will be fine .. you might kick off an unexpected pt of resin..learn how far you can run it before it kicks off ..

Keep up the good work and pics .

YD.

 

[odleon]

Re: ?? on repairing FG jon boat.

Cool. I actually do car audio, so i have experience with FG. Ive just never messed around with boats and structural stuff.

Im used to doing 5-8 layers of mat on subwoofer boxes, so this should be easier.