Grand Banks 42 Destiny Refit stage 2

Now winters set ive decided to get stuck into my own boat... part 2 of the Refit! We have enjoyed sleeping in the front double berth all year, but there is so much more room in the back, more like a minny lounge, so im going to build a double bed. There are some good Google images to copy, as most GBS were fitted with doubles, mine was unusual with two singles. As you can see ive gutted the cabin and started replacing the rotten bulkheads behind the water tanks. Its a job id know about when I bought her, but I was surprised at the extent of the deterioration. A bad design on the old Woodies, the rain water gets in around the aft deck hatches and works its way down behind the water tanks. Someones already replaced these once, so its an on going problem i will try to solve. The tanks are only about 10 years old so they are fine, the new plywood bulkheads i will epoxy seal to help prevent the rot happening again.

You can see where ive started cutting out the bulkheads. (grey water tanks behind). The ordinal single bed to the right will stay, the other has been removed along with the chest of draws creating a large space for a double bed. The floors, hog, stringers and former's are all in great shape!

This is an image off Google giving me the idea of the new layout....Ill use all the old Teak woodwork so i can make it look as original as possible. 

Stage 2 coming soon.... Xmas time Job!! 

AN INTRODUCTION TO LPG INSTALLATIONS

I'm presently refitting my gas system on my Grand Banks 42 after numerous failures from a recent BSS inspection. Ive had this article on my website for years so thought id post as an introduction to LPG installations. 

Any fuel that produces a flame consumes oxygen when burning and gives off carbon dioxide (CO2) and water vapour. Boats interiors have little volume, and cabin spaces are normally well sealed (they must be to be watertight). The oxygen available in a closed cabin can be consumed quite rapidly. Insufficient oxygen makes the fuel burn improperly and, instead of producing carbon dioxide, it begins to form a deadly carbon monoxide (CO). The combination of oxygen loss and carbon monoxide build up can be fatal-it has caused a number of deaths over the years. Always insure adequate ventilation when burning any fuels; this includes running diesel engines, which sometimes obtain their air via the living spaces in spite of the fact that they should be independently vented. Do not use an appliance for heating unless it is so designed. Never leave a heater on overnight unless it is vented outside the cabin area and adequate air supplies are assured.

LPG (Liquid Petroleum Gas) is kept under pressure as a liquid and when released becomes a heavy flammable gas that is much heavier than air. The aim therefore is to minimise the risk of this gas escaping into your boats interior, where it could quickly accumulate, creating an explosive ‘mix’ of gas and air.

This chapter concentrates on how best to store LPG, how to supply your gas appliances and how to protect the gas system and installation from heat and impact damage. It is always strongly recommend that any work on LPG systems is carried out by a competent gas fitter.

GAS

The two main types of gas in wide spread use are propane and butane. Butane and propane both liquefy at low pressures and temperatures. As gas is pumped into a cylinder at ambient temperatures, these pressures are reached quickly. Then as more gas is pumped in, it liquefies-with temperatures and pressure remaining relatively stable. When a full cylinder is rocked from side to side, the liquid can be heard sloshing around inside. In higher ambient temperatures, pressures in an LPG cylinder will increase somewhat, but never beyond 250PSI; in lower temperatures, it will decrease.

As long as an LPG cylinder is kept upright, there will always be gas at the top, liquid at the bottom, and stable pressure-until the cylinder is almost empty. At this point the pressure begins to fall as the last of the liquid evaporates.

The principle difference between butane and propane is the former liquefies at higher temperatures and lower pressures for the latter. In extremely cold weather, liquid butanes rate of evaporation from a cylinder can slow to the point at which appliances fail to work properly. In these conditions propane should be substituted.

In the UK appliances operating on Butane do so at a pressure of 28 millibars and Propane at 37 millibars. It is not generally possible to change from one fuel to the other without changing the regulator, hence the cylinders and regulators have different threads and fittings to avoid mishaps. As a point of interest butane has a higher calorific value and a slighter hotter flame temperature.

SAFETY PRECAUTIONS

LPG forms a dangerously explosive mixture when combined with oxygen in the air. LPG is considerably heavier than air-gas leaks sink to the bilges. LPG leaks are particularly dangerous on boats: Small leaks can remain undetected in deep bilges. A tiny spark (which can be generated by static electricity on any boat) can blow the boat apart.

INSTALLATION PRACTICES

Compartment requirements: Gas bottles, both in use and in storage, must be kept well secured in compartments that are sealed from all machinery and living spaces, and vented overboard. LPG compartments need to be vented from the base with a minimum internal diameter of 19mm (B.S.S exemption to 12mm on older vessels), which slopes continuously downwards so that no water can form a U-trap, which exit’s the hull above the waterline at all angles of heel. This is continuously picked up during surveys, many drain hoses are found to be looped up and contain water! All gas vents must exit well clear of engine exhausts, ventilators, and air intakes. Gas cylinders must be secured in an upright position (again very few cylinders during surveys are secured properly). If an LPG cylinder tips over, liquid instead of gas might come out-with potentially dangerous results.

MARINE GAS DETECTION

Suitable means for detecting the leakage of gas should preferably be provided in each compartment containing a gas-consuming appliance. Gas sensor heads should be protected against damage caused by water and other corrosive agents, and the risk of mechanical damage. The consequences of an LP gas leak on board a boat can be disastrous. Every year there are deaths and injuries on board boats, which could have been avoided with the installation of easy to use and cost effective gas detection equipment.

LP Gas is not regarded as poisonous but is explosive and can lead to devastating explosions if it builds up to sufficient levels. It is measured using what's called the Lower Explosive Limit (LEL). This means that when the concentration of gas reaches 100% LEL it becomes explosively dangerous (i.e. if you lit a match it would go bang). Most gas alarms are calibrated to alarm at 10% LEL, well before the gas becomes explosively dangerous.

A strong smell of gas can be noticed when the concentration is only 0.5% to 1% LEL because gas suppliers add a harmless but strong smelling chemical to the gas. Despite the strong smell this level is not dangerous and therefore the alarm will not sound. This reduces the possibility of false alarms.

Westerly Centaur

I had a trip out to Loddon on the South Broads yesterday to survey this Westerly Centaur. She was designed in 1968 by Jack Laurent Giles as a more modern and roomier replacement for the existing Westerly 25. She was probably the first mass-production yacht to have had the design tank-tested before a prototype was built, and this, plus Laurent Giles's earlier experience with bilge keel designs, was probably the reason for the Centaur's good performance under sail. Looking at a roomy boat with good headroom and a powerful diesel makes many people regard Centaurs as motor-sailers. They are not - they actually sail very well, although as bilge-keelers they are always going to be slower to windward than similar sized fin-keelers.

The sailing performance is helped by carefully designed bilge keels which are handed port and starboard with a two degree toe-in, so that once the boat heels under sail the more vertical leeward keel is developing lift to windward. Most Centaurs had 25 bhp Volvo diesels like this example, though a few were built with different engines, usually the smaller 13 hp Volvo, though some had 25 or even 30 hp Watermota diesels.

As with all other Westerly Marine yachts the Centaur was massively built. This was partly a result of previous building experience within the company and also a reflection of the state of GRP technology at that time. All Centaurs were built to Lloyds specifications which meant that the building processes were rigorously monitored and all materials had to be approved by Lloyds in order that a certificate could be issued. Although no longer in production they still represent excellent value for money. I should state that as they were 'over built' and the hull was thick they are vulnerable to osmosis, and most of this age have been peeled and treated with an epoxy barrier coat, so don't be surprised to find some blistering on the underbody.  

Sessa 42 for sale in Norfolk UK

I must apologise for no BLOGGING this week! Ive been trying to catch up after probably one of my busiest seasons. Things will slow now up until Christmas, maybe its time for a holiday!

Anyway, I was back at Norfolk Yacht Agency yesterday to Survey another stock boat owned by them. This was the older model Sessa 42 (2006). Italian, and built with a solid-fiberglass bottom and foam coring in the topsides. The hull and deck are bonded, screwed and then sealed with fiberglass tabbing around the interior perimeter, keeping the boat completely dry. She is Europe’s Category B for recreational boats, which means she can apparently withstand 40-knot winds and 13-foot seas! She certainly performed well on the river trail and we reached a top speed of around 32 Knots with her punchy 310HP Volvos on duo sterndrives.

She was highly maneuverable on the river trial and incredibly fun to drive

Electrolysis! 

New props please!

310HP Volvos

Surveyors comments: Surprisingly well built and well put together with quality parts. Stylish inside and out, roomy and comfortable.

Thinking of Buying a Boat and Need Help? I specialise in Boats of all types, and I will assist you to make an informed decision. Contact me for a detailed and comprehensive report at:  steventruss1@aol.com

Concrete 40ft Motor Sailer

Back in the day these Ferro Hulls were popular with the DIY builders. This was an interesting assignment today. The aging owner had passed the boat down to his 23 year old grandson and he wanted to know if it was worth while carrying on with the project. The instruction was to check the vessels structural integrity after sitting in a shed for the past 40 years.

Carefully cured mortar over a steel mesh and rod matrix, results in a structure that is tough, strong, will not burn, resistant to chemicals, not affected by ice and gets stronger with age.

Ferro cement boats were first built around the 1850's, loads still survive and are floating today. During WWII pretty large vessels were built of the material. I remember four huge floating concrete barges we use to fish off when I was a kid growing up in North Wales.

Though many good yachts have been built of this material, like the ones by Windboats Ltd. to Lloyd's approval, the reputation has been dead in this country for some time. Europe is catching up with this opinion, for a number of reasons, difficult and expensive surveys being one!

Anyone interested in the method should try to find Jay Benford's book on the subject "Practical Ferro-Cement Boatbuilding" it covers the methods and correct ways to build lighter, stronger ferro yachts. Benford Design Group or Tiller Publications may still have a copy around.

The birds and ...

the Bees! 

The plans came from Auckland in NZ

Surveyors comments: If one can get over the idea that concrete really can float, I think ferro built well is a useful boatbuilding material. The element that provides the strength (the meshing) is hidden and can not be inspected, except by drilling holes through the hull. Usually over weight, slow and sluggish, and difficult to sell second hand...Get an INSURANCE quote before you buy!

Thinking of Buying a Boat and Need Help? I specialise in Boats of all types, and I will assist you to make an informed decision. Contact me for a detailed and comprehensive report at:  steventruss1@aol.com