A fathom is the unit of measurement traditionally used when referring to the depth of the sea,or in some cases ,the length of ropes and cables. The word comes from the old English word faedm ,meaning to embrace, and is a measurement across the outstretched arms of a man,approximately six feet in a man of average size; the length of a nautical fathom is therefore six feet,roughly two metres. The term is used less and less frequently with the growing tendency of most countries today to adopt the metric system measurement as the datum shown on the nautical charts they produce.

Sea water is rarely still,it is usually moving in waves,tides or currents.Waves are caused by wind blowing across the surface of the ocean.

 The height of a wave is determined by the wind speed,the time the wind has been blowing,and the distance the wave has travelled over the ocean.

Water does not move along with with the waves. Instead the water changes shape as a wave passes,moving in a roughly circular motion,rising towards a wave crest as it arrives and falling as it passes.

This motion can be seen by watching a boat.The boat bobs up and down as the wave moves past it,but does not move along with the wave.

The country in which a ship is registered is indicated by a flag known as an ensign.Traditionally,this flag is flown from the gaff,which extends from the top of the foremast,just aft of the bridge,when at sea or the staff on the stern of a ship whilst alongside a quay.British vessels may fly one of three different ensigns,which consist of a union flag on one of three coloured backgrounds.The red ensign is flown by British registered merchant ships. The blue ensign is flown by British naval auxilliary vessels,such as those operated by the Royal Fleet Auxilliary as well as by a merchant  vessel if the commanding officer has attained the rank of commander or above in the royal naval reserves.The white ensign is flown by all ships of the Royal Navy.When hoisting the  ensign,a sailor must be very careful and ensure it is flown the right way up.An ensign flown upside -down traditionally indicated distress on board a vessel,usually mutiny!

You may have observed a mark painted on a ships' side at approximately midships, near the sea level.That mark is called the Plimsoll Mark and it indicates the draught levels to which a ship may be loaded for varying conditions of season and location.The Plimsoll Mark can show up to six loading levels [tropical fresh water,fresh water,tropical sea water,summer sea water,winter sea water, and winter North Atlantic, for vessels shorter than 100metres.] This mark is accompanied by another,consisting of a circle bisected by a horizontal line with letters which indicates the registration society [i.e." LR is the code for the "Lloyds Register",whereas "RI " is the code for the "Registro Navale Italiano"]. the horizontal mark on the registration mark indicates the summer freeboard. The Plimsoll Mark originated back in the days of sailing ships where many ships were lost due to gross overloading. These disasters at sea resulted in heavy losses for Marine insurance companies, including Lloyds ,hence the development of the Plimsoll Mark to guide ships' masters and shipowners to load their ships safely

A bulbous ships bow is a feature of many modern ships hulls.It is characterized by a protruding bulb at the bow of the ship below the water line.Due to this ,a bulbous bow is usually only visible when the ship is in dry dock or out of ballast waiting to load cargo and therefore floating higher than usual when at sea.The presence of this bulb modifies the flow of water around the hull,thereby reducing drag[friction] and affording an increase in speed,range and fuel efficiency.In ships that have had bulbous bows fitted,gains in fuel efficiency of between 12 and 15% are standard.As these factors are particularly important for almost all applications of maritime vessels,bulbous bows have seen widespread adoption since their development  

 

I'm not sure how many fibreglass boats with osmosis that I have seen over my many years in the boat broking trade, but I can tell you that it would be several hundred.

The very word osmosis seems to strike terror, fear and loathing among boat buyers but it is, however, very unlikely in my experience, to be a serious enough problem that could put a vessel at risk. In other words, not a structural issue that could cause a boat to take on water into the hull and founder. Osmosis is usually only a minor problem that can be easily checked and handled when the boat is pulled out of the water for the annual antifouling job.

Most people would know roughly what osmosis is, but for those who don't, it 'shows' itself as blisters on the hull (normally under the waterline), these can be just a handful or perhaps hundreds.. The blisters are usually approximately the diameter of a fingernail and about one or two millimetres proud of the hull surface.

The next time you have your boat out of the water, clean off the marine growth with a high pressure cleaner, and while the hull is still wet, have a good look below the waterline. If you spot a slightly convex area, carefully prod it with a sharp spike (nail will do) and if a foul acidic smell is evident (it's a bit like the smell of a crushed ant), then your boat more than likely has an osmotic condition.

The generally accepted main cause of osmosis is that it originates during the 'laying up' process of the fibreglass when the boat is being built. Fibreglass boats are ideally built in controlled low humidity factories these days, to reduce the opportunity for moisture in the atmosphere to become trapped in the glass fibre strands.

Twenty or thirty years ago the risk of moisture was perhaps not as well known and boats with osmosis are often but not always, older boats.

So if small amounts of moisture does get trapped in the building process, eventually the result is a little blister.

Usually these can be easily identified and dealt with by carefully grinding a very shallow area around each blister to enlarge the area. This can then be carefully cleaned and reglassed, sanded, primed and painted. A competent trained shipwright ca do this easily or can show you how to do it yourself.

In very servere cases (rare), the upper level of gelcoat may need to be carefully shaved back one or two millimetres with a special planing power tool. The hull surface is then brought back to a finished standard with a new outer coating of glass and gelcoat. This can be expensive, but fortunately it's very unusual that this will be necessary and I have seen only a handful of cases in my many years in the trade.

So if you are looking at buying a boat, get a good marine surveyor to check the hull: there are also plenty of articles on the subject which can explain it better than I can, so if it's something that worries you, have a look on the 'net'.

If you have your heart set on buying a nice boat, don't let a little bit of osmosis spoil it for you, it may be quite safe and a simple matter to monitor it from time to time.

Happy Boating !!!

Chris and Lach 

So much has been written and talked about lately when it comes to the topic of boat pens - or more to the point, the lack of them in the metro area - that I thought I would bring up another form of securing your vessel when not in use - THE RIVER SWING MOORING.

The Swan and Canning River systems hold a multitude of moorings to suit vessels from as small as 5 - 6 meters upto around 20 meters in length. These mooring sites are leased off the Dept. of Planning and Infrastructure for a reasonable fee, with all costs of the upkeep of the mooring tackle being met by the mooring lease holder.

River moorings are a very cost effective way of securing your vessel in comparison to a river pen, but let's look at some of the other pros and cons.

There are a range of river moorings available now, to suit various length vessels. Pens are very scarce, and usually involve years of sitting on waiting lists at various boat clubs, or buying a boat with an existing pen. ( Perth is not the only part of the world to have a shortage of pens. Boating meccas like Sydney and parts of Florida all rely heavily on the use of moorings to secure thousands and thousands of vessels.)

ACCESS - Pens win this one every time. Walk up and jump on. Moorings usually involve a dinghy, some oars, some rowing ( exercise! ), possibly even teaching the kids to row in the process (bonus ! )

FACILITIES - Pens win this one too. Shore power and fresh water a neccessity -right ? For some modern, high power use boats for sure, but for a big number of boats, a couple of good solar panels and a regulator will keep the batteries topped up and ready to go. A bonus is that  at Rotto the solar panels will reduce the need to " fire up the generator" to keep the batteries charged.  

With water shortages, isn't it time for boaters to reduce their fresh water useage too ? A couple of buckets of fresh water will rinse off the saltwater in no time.

COST - Moorings win here. Mooring lease holders will generally outlay less than $ 1000 per year to lease and service their river mooring. Pens - well - anywhere from $ 250 per meter per year upto $ 1,000 per meter per year and beyond !

SUNSET DRINKS - Picture this- it's a balmy autumn arvo, the breeze is dropping, and the kids are bored. Time to pack a drink or two and some nibbles, and head down to the boat. Have the kids to row you all out to the boat and relax...... Watch the sun go down, drop a line or a crab pot, spot some dolphins, polish the stainless, order some delivery pizza,   you could be in another country.

It's too easy to say "If I don't have a pen, I won't buy a boat", but if you buy that boat and put it on a river mooring, you can start boating NOW, and really enjoy our unique boating lifestyle.

You might actually find another bonus for boating in our beautiful part of the world - the river swing mooring.

Lach ( mooring leasee of 12 years-coudn't you guess) and Chris.

 

I have learnt a lot about boating from my father, who learnt from his father, who learnt from his father, who learnt from his.....

In my early youth, my Dad Peter, told me an absolute 'corker' about what can happen when dropping anchor.

In the 1920's my Dad used to load up his 16ft gaff rigged boat with tins of canned food, really lovely stuff like braised steak and onions, camp pie ( commonly known as tinned dog ), baked beans, etc., a couple of loaves of bread, flour for damper, spuds and a few bottles of beer, a block of ice, some fishing lines, gidgees ( spears ) for crays, a kerosene tin to cook the crays, a sweater and a couple of pairs of shorts.

He would take one of his 'scaley' mates with him and set off down the Swan River from Claremont to Carnac, Rottnest or Garden Island and spend a week fishing, swimming and camping on the nearest beach at the end of the days' activities.

In the late 50's I found out what my dad meant by camping. Setting up a tent was too much like hard work, so it was usually a case of just sticking some oars in the sand with a sail draped around to make a semi enclosure and make a 'blackfellas' fire with a few bits of brush or driftwood to warm up the 'tinned dog' and boil the 'billy'. It was always interesting to shine a torch around the beach at Carnac to spot the nice Tiger snakes among the dried kelp nearby. I should never have told Mum about this, as later on she 'cooled' somewhat on the idea of us kids going to Carnac with dad.

Anyway, I'm getting away from this weeks' topic, anchoring.

My old man told me about a trip he once did to Garden Island with an ex school chum named Bill ( we won't worry about the surname here).

They sailed over to a little bay at the North end of Garden Island known as the 'Pig Trough' ( I don't know why they call it the Pig Trough ) on a gentle 'Easterly' breeze.

Arriving at the anchorage in about 15 feet of water, my 'old man' rounds up the boat into the breeze and brings the boat to a stop. Dad sends Bill up for'ard to drop the jib while he deals with the mainsail.

At the same time my father yells out " hey Bill, drop the pick now, mate" and hears an appropriate splash of an anchor on its way to do its' work on the seabed.

Shortly after this point Dad is still busy 'down aft' furling the mainsail and says to Bill " come back here mate and give me a hand with this sail."

No Reply !!! and when my father turns around to see why Bill hasn't answered, Bill has disappeared altogether!

This is a real mystery until Dad looks over the side of the boat and in the pristine clear water there is Bill plain as day on the bottom keeping the anchor company !!

So the 'old man' dives in and rescues Bill who had a very close shave indeed !

Bill had chucked the 'pick' over the side without noticing that he was standing in a coil of rope and you guessed it, this was the anchor rope.

So the moral of the story is: don't just chuck your anchor over the side, make sure the rope or chain is clear or you might wind up in 'Davey Jones's Locker' with the anchor rope around your leg  !!

Happy Boating

Chris Mews

 

Best wishes from Chris and Lach.

We've all seen it. That lovely looking boat cruising down the river being stalked by clouds of billowing black smoke. " What a shame" we mutter under our breath. " Looks like he's up for some big bucks" others will say. And the wise old man on the hill will be thinking, " Bloody good feed of mussels going to waste !"

There is every chance that if you're experiencing loss of speed and-or revs, and you're blowing a bit more black smoke than usual, and the engines vitals are looking ok, you've got a fouled prop/s.

It's not uncommon, especially when the water is warmer, for your fresh antifoul to be clean and your prop/s to be attracting serious growth inside 4 weeks. In this age of " we've got an answer for everything" ( just ask Kevin '07 ), there are a few expensive treatments available to counter marine fouling to propellors, and even claim enhanced overall performance and improved fuel consumption. I've heard that these treatments work very well most of the time, but if your boat sits idol for more than a couple of weeks, marine growth, especially barnacles, can establish themselves and propogate with gay abandon. It is certainly not uncommon, that during a routine pre purchase out of water hull inspection we will find 'treated' props with barnacles firmly attached.

I suppose the point I am getting at here is: Clean prop/s have a major positive effect on the optimum performance of your vessel.

So, if your craft has dropped a knot or two, don the mask and snorkel, jump in and have a look, you just might be surprised with what you find.

If your prop/s are raw, that is bare bronze, a paint scraper, scourer pad and medium wet and dry sandpaper will be sufficient to bring 'em back to their best. If they are antifouled or 'treated', a gloved hand could be used to gently remove the growth. Please remember that it is an offence to tamper with your antifouling whilst your vessel is in our beautiful waterways - so major defouling should be done on the hard stand.

Similarly, a dented, bent or jagged prop blade can severely reduce your props' efficiency. Electrolosis is another factor that can effect your props' performance, should it take hold. These problems will require you to enlist specialist help.

There you go - look after your prop/s and you'll get there sooner, and at less cost.

Cheers and safe boating

Lach Simpson and Chris Mews

In our trade as boat brokers, we spend most of our time on or near the waterfront, observing all manner of boats being lifted or pulled from the water and having all kind of jobs done to them.

Woden boats can be a special joy to the people who own them and others who just admire them from afar. Special care, however, should be given to them to prolong their life. I have a long term friend who has a wooden boat built in 1896 and he uses it regularly, and I'm sure that with proper care, a wooden boat can last longer than some of our fibreglass boats. I think that this particular boat will, with care, still be around long after I'm gone from the scene.

Lifting a wooden boat by a boat lifter is usually fine, but if it's a planked ( carvel, clinker, or double diagonal planks ) it's usually better to ask the boat yard to use 4 straps instead of the usual 2. This is because wooden boats of this kind will tend to flex somewhat and the extra straps provide more support and don't put unneccessary strain on the hull. ( A bit like an old girl or bloke with a jock strap!)

If the boat has hard chines, it's best to have some flat wooden blocks/pads made up that fit just above the chines. This is because the pressure of the straps on the hull at the chines can compress the hull at that acute point and concertrate most of the vessels' weight onto that point rather than spreading the load evenly.

These blocks or pads are usually about 2' long and about 6" high and can be permanently fastened to the hull by a shipwright, or can be made up and just hung over the gunwhales by ropes at the time of lifting. ( They fit snugly between the hull and the straps.)

The traditional slipway, or railway and cradle, is my preferred method, because the full weight of the boat is normally supported on the keel and not on the planks, so the side arms of the cradle merely hold the boat in the vertical position. The keel does the work ! In this way, the boat is not likely to temporarily distort which can stress the hull.

It's always a good idea to make sure the shipyard puts blocks and wedges under the full length of the keel, so that the boat is fully supported.

Don't forget, If you want to have your "2 bobs' worth" with your observations about boating tips, anecdotes, etc... send us an email.

 

Happy Boating

Chris Mews and Lach Simpson

 

In current economic times, some boaties that were looking to upgrade to something new, have had to reconsider this exercise and instead, are looking to repower their existing vessel.

 

Now this is all well and good, and in most cases quite achievable, but let's look at the big picture. The reasons for re-powering are usually 1. more speed, 2. better reliability, or a combination of both.

 

Let's do a rough break down of the costs of re-powering a single diesel shaft drive boat with a different ( usually higher horsepower ) motor. The main items to consider are:

 

Boat out of water and hard stood for at least 2 weeks

 

Bulkheads,flooring etc. removed.

 

Old motor removed and disposed of.

 

Engine beds removed and adjusted, or replaced.

 

Shaft, shaft bearings, I brackets etc. upgraded or replaced.

 

Propellor replaced or re-pitched.

 

Fuel system re-aligned and re-calibrated.

 

Exhaust system replaced.

 

Electrical system upgraded - new loom and switch panel fitted.

 

New motor fitted.

 

Shaft aligned with gear box coupling.

 

Bulkheads, flooring etc. replaced.

 

Launch vessel.

 

Run up new motor and make necessary adjustments.

 

Have a beer ! ( or 2 )

 

As you can see, at nearly every step of this process, you are going to need professional help - expensive professional help.

 

So, for example, if your current 38' flybridge cabin cruiser had a serviceable but tired 320 hp diesel motor fitted, it's market value might be around $ 130,000. If you were to re-power this boat with a new 450 hp diesel motor, thecost for this re-power could range from $ 75,000 to $ 100,000( approx.) This boat now owes you in the vicinity of $ 205,000 to $ 230,000. But the market value of this vessel has only increased by a small percentage of the money invested in the new motor.

 

If you really love your boat, and intend to keep it for many years, then the exercise could well be justified, with the costs written off against the extra performance and pleasure derived.

 

We regularly say to clients that if you are considering re-powering your boat, have a good look at the market first. There-may be that boat you've been looking for with the features the family have always wanted, and the cost mightn't be a whole lot more than the value of your current boat, plus your intended outlay for the re-power, and you haven't lost out on resale value.

 

Now, if only there was a nice Randell 41 with twin Cummins..........

We welcome readers own experiences with anything boating, so drop us a line !