Hull Thickness & New Stabilisers 1984 61MY

[scottinsydney]

Ive seen many posts on hull thickness and got a real surprise when the old Naiad 252 stabiliser system was removed this week. Being replaced with a Vetus system. Thought I would post a few photos from the slipping this week. In the end the old blocks and rusted old Naiad parts came out as one and we replaced the blocks. So we are now all ready to install fins at next slipping in about 3 months time. I actually thought the hull thickness would be one inch or 24mm, but it turned out to be 1/2". There was quite a lot of flex in the block area. The shipwright now wants to fibreglass in for and aft the block to add rigidity and to spread load. However old system worked for over 35 years without glassing in. We have completed the hydraulics and hoses inside the boat and making use of old engine mounted hydraulics pump. Project so far has taken 12 months.

[scottinsydney]

More photos...,The boat was sold to dealer Hatteras of Ft Lauderdale in1984 who finished off the interior and added the old Naiad stabiliser system. Not sure what yard or when 9' cockpit extension was done. This set of photos show the new stainless bush and how it was presented to the new blocks. Boat is now back in water with two hatches over the holes awaiting new fins.

[Glory]

Ive seen many posts on hull thickness and got a real surprise when the old Naiad 252 stabiliser system was removed this week. Being replaced with a Vetus system. Thought I would post a few photos from the slipping this week. In the end the old blocks and rusted old Naiad parts came out as one and we replaced the blocks. So we are now all ready to install fins at next slipping in about 3 months time. I actually thought the hull thickness would be one inch or 24mm, but it turned out to be 1/2". There was quite a lot of flex in the block area. The shipwright now wants to fibreglass in for and aft the block to add rigidity and to spread load. However old system worked for over 35 years without glassing in. We have completed the hydraulics and hoses inside the boat and making use of old engine mounted hydraulics pump. Project so far has taken 12 months.

What lead you to select Vetus?

[scottinsydney]

I purchased the boat with a non functioning/rusted stabiliser system. I did some initial enquiries about possibly rejuvenating the old system, but it was clear everything in the engine rooms would need to be replaced. When I did my sums, including the cost of moving the boat 700 miles to the nearest dealer it got too difficult. Having fly-in and fly-out mechanics would not work either.

I have also owned a boat parts business for 20 years, so the thought of spending so much money and not being involved was part of the equation. There were three different agents where we have tie ins and who sold different stabiliser systems. But again the agents were 600 miles away. There was also the consideration that we have the existing holes in the hull, and none of the existing systems would equal the measurements of the old system's through hull parts.

Vetus said that they would make the new stainless bushes to fit the existing hull holes. If the old blocks were ok it would all fit. Vetus also sells each part of the stabiliser system as a component, so I could order what I needed to suit my 18 month timeline. This was a huge factor in their favour.

So in the past 12 months, we have removed all the old hydraulics, stabilisers, hoses, installed the new hydraulics, new electrics and cables, new blocks. The fins will arrive in about a month's time and we will slip the boat again to quickly install these. The only work I did not do myself was the removal of the old blocks and bushes and repair to the hull. The boat needed to be slipped for this, we did not know what to expect and fortunately there were no nasty surprises. A real surprise was the 1/2" thickness of the hull and it did flex. New wooden blocks had to be made. The work took two shiprwrights three full days to complete. The bill to do this work plus slipping fees was about what I thought it would be. But it achieved all its goals.

Ft Lauderdale Show... I visited the 2016 show and saw the Gyro Gale Air compressor stabiliser system. I did not know about it. In hindsight, we could have used the existing compressor and air tank in the port engine room, run simple air hoses, done away with the wooden blocks, and it would have worked at rest with a full air tank guarding against an occasional boat wake. If I had only known...... All the other brands I looked at had fine systems to offer too. But Vetus would allow me to oversee the project myself, choose my own slipway close to home and shipwrights. Obviously they have carefully watched each step of the way.

I've enjoyed the project and am now into the final phase.
Junction Box and Tank.jpg

Photo of new tank, valve block & junction box during installation..we were able to use old stabiliser systems cabling from wheelhouse to engine room for some of the wiring requirements.

[Pascal]

Is that balsa core in the bottom? Looks like it but i didn't think hatteras cored any hull bottom

[scottinsydney]

The hull was solid fibreglass. The core i think Pascal is referring to was a loose piece of timber that was sitting just inside the hull opening.

[Pascal]

I was talking about the second picture, showing the entire hole. For some reason it looked like balsa core

[scottinsydney]

It was all fibreglass.

[scottinsydney]

The project continues....

The shipwright who installed the boxes suggested they be epoxied to some new cross bearers so as to improve the side strength of the hull. He suggested this because the hull flexed about 1.5" when they were trying to remove the old boxes. I agreed and decided to take on the project myself.

This involved buying some rounded 90 degree timber mouldings to butt up against the blocks. I reversed the wood to make 180 degrees between the internal stringer and the side of the hull. Used West System slow set epoxy, but still managed to get the ratio slightly wrong and watched half of my first batch steam then bubble and set rock hard. Must have been hot because it meltted the plastic spoon! Subsequent batches worked well and the first timber moulding is in place with a total of 1/2" of cloth and a 3/4 pint or so of epoxy and hardener.

blockstrengthen.jpg

QUESTION HYDRAULIC PUMP:

The old Vickers hydraulic pump has not been worked for 6 years and was run dry by PO. The pump's pressure is wrong anyway for the Vetus system (needs say 2000 psi and 2-3 gallons per minute). I have found a Vickers supplier in Oz, but I need to know how to determine the rotation of the PTO on the starboard 12V71. Does anyone know the answer?

Vickers Pump.jpg

[mykim]

People often blather on about how thick the hulls are. As you progress down toward the keel it does get pretty thick. And they taper out toward the water line. It's tough stuff though. Great pictures.