Ribtec 725 refurbishment

[beamishken]

Originally Posted by Pipster100

A local marine engineering company who build tanks built me a new one designed to be bolted in place with studs welded on top and brackets made so it could be bolted to the main stringers. Although the tank has angled sides it’s flat bottomed and Ribcraft glass a flat deck above the hull for the tank to sit on so very robust. The baffles in the tank (185 litre) add strength too.

I recently had to replace the complete wiring harness , control cables & hoses , basically everything in the underfloor trunk in a ribcraft 585 due to fuel ingress ruining everything. Reading forums since that isnt an isolated case either several other folk with similar experiences.

[kevinsc]

Originally Posted by Pipster100

Should have mentioned the tank is sitting on 6mm rubber matt too.

Sounds like pipster the tank is well strapped in and shouldn't moved in the rough.
Cheers Kevin

[Pipster100]

Hi Kevinsc,
Correct, the tank is well secured. You can see in the photos the old tank prior to removal and stained foam. Was a lovely job removing and cleaning ready for the new tank.
The brackets were both bolted and bonded with Sikaflex to the deck, at the rear of the tank I glassed a beam in for both securing the tank but also to support the deck when replaced.

[kubcat]

My 9m Ribtec also had soft wood around the bow that required repair maybe 10 years ago..

The design looks quite different to this boat so not sure I can assist with how it is designed internally.

I might have some photos of the repair so I will see if I can dig them up.

[kevinsc]

Hi pipster
I remember that job of removing the foam from under the fuel tank it was messy and because of no drain holes in the back bulkhead it was wet. I'm using the old fuel tank so will have to foam the tank back in and I don't have as much space under the deck as you for the fuel tank.
Kubcat
It would nice to see pics of your deck as mine was soft in places.
Cheers Kevin

[kevinsc]

Hi All
Not had much time recently to get stuff done on the boat. But today I got the rest on the bulkheads and ribs bonded in place and started to cut the deck at the bow making it look like a boat again.

[tinker]

Nice work, what plywood do you use?

[kevinsc]

Hi tinker
Thank you for the comment it has taken a bit of tweaking to get it fitting well. I have used marine plywood for the stringers, bulkheads and ribs.
Cheers Kevin

[beamishken]

Have you added extra bulkheads or just followed the origional ones? Looks like the proverbial brick shithouse gonna be a serious amount of glass and resin to glass over all that lot
Are you running underfloor ducts for the services? What are you going to use for them?

[kevinsc]

Hi Beamishken
I've added a couple extra bulkheads where the inboard engine was and the end of the fuel tank and hope it will take alot of punishment out in the open sea. It will take a bit more glass and also was going to glass the underneath of the deck as well but I hope it will take a long time to rot. Once glassed I will run green reinforced flex pipe 40mm down the middle to the back, but not sure about getting to the A frame.
Cheers Kevin

[beamishken]

Once its all glassed should last a very long time my dilemma is how to fix the floor to stringers & bulkheads without creating a leak path for water. Just using bonding paste doesnt seem right & putting screws in equally not right. Seen both ways but not 100% on either method. I do a layer of glass on underneath the deck too but many manufacturers don't bother
Looking good though

[kevinsc]

Hi Beamishken
I did think of water tracking down the screws, so I'm going to run strips of wood down the sides of the stringers,bulkheads and ribs so not to damage them. When placing the deck on I'm to run silkiflex on stringers etc and in the screw holes and fill screw heads with filler, 4 or 5 layers of glass hoping that will seal it from water tracking.
Cheers Kevin

[paulbrown22]

Originally Posted by kevinsc

Hi Beamishken
I've added a couple extra bulkheads where the inboard engine was and the end of the fuel tank and hope it will take alot of punishment out in the open sea. It will take a bit more glass and also was going to glass the underneath of the deck as well but I hope it will take a long time to rot. Once glassed I will run green reinforced flex pipe 40mm down the middle to the back, but not sure about getting to the A frame.
Cheers Kevin

I'd definitely glass the underside of the deck while you're going to all this trouble. That's the thing that killed my 9m Ribtec after ~14 years - to save £30 of supplies during build they didn't bother to glass/seal the underside, and given the constant slight moisture under there given the bilges it was going very soft in places and similarly the whole thing had to come up and be replaced.

[kevinsc]

Hi Paulbrown22
Your right, when I removed the old deck it was soft in places and mouldy underneath so as you said for the slight extra cost to glass underneath to prolong the life of it is a no brainer. Do you any pics of the deck getting redone.
Cheers Kevin

[beamishken]

Originally Posted by kevinsc

Hi Paulbrown22
Your right, when I removed the old deck it was soft in places and mouldy underneath so as you said for the slight extra cost to glass underneath to prolong the life of it is a no brainer. Do you any pics of the deck getting redone.
Cheers Kevin

I recently holesawed decks in a 585 ribcraft & a 8.4 redbay, both well respected builders & neither had glass on the underside of the decks

[kevinsc]

You would think that well known rib builders would glass underneath the deck to keep there boats around for longer for their reputation. Everything is made to a price and sold at a high price.
Cheers Kevin

[fastasfox]

Originally Posted by kevinsc

You would think that well known rib builders would glass underneath the deck to keep there boats around for longer for their reputation. Everything is made to a price and sold at a high price.
Cheers Kevin

That was my first thought too, but then if water gets into the ply.....and it will, through screw holes etc I guess it would just sit there and rot.
I think let it breath is the order of the day.

[Pipster100]

Hi,

Just remember that depending on the type of resin you’re using and making an assumption here that as you’re doing a RIB refurb you’ll be using polyester resin that it’s not waterproof, even gelcoat isn’t fully waterproof which is a contributing factor to fibreglass boats getting osmosis.

Have a look at epoxy sealers, when I recently replaced my tank and had to remove a section of deck to get the tank out, any exposed timber bearers were treated with epoxy sealer prior to the deck going back down. Luckily my deck was solid so I could use the section I removed.

Not saying this is definitely the route you should go but worth considering.

[paulbrown22]

Originally Posted by kevinsc

Hi Paulbrown22
Your right, when I removed the old deck it was soft in places and mouldy underneath so as you said for the slight extra cost to glass underneath to prolong the life of it is a no brainer. Do you any pics of the deck getting redone.
Cheers Kevin

Sadly very few pics as the guy doing the work dropped his camera and knackered the memory card. A few fuzzy photos he managed to retrieve attached, all of the work he first did under deck on the stringers. I don't actually have any of the deck itself going down!

[tinker]

Look at the state of that stringer on the right, bet the deck was bouncing about a bit with that underneath it all, something satisfying watch all that rot being chopped away. Nice update BTW, very interesting.