Note we do not have any financial arrangements or other interests in any the products mentioned here!
For just about every question, there are almost as many different opinions as there are sailors. And, most of these different opinions are in fact valid for the specific individual with their particular boat and their unique mission. That said, below are our opinions based on our experiences to date. We reserve the right to change them, or even admit they are wrong, at any later date :)
6. If you got a new boat, would it look like Hawk or be different?
15. Would you ever consider cruising aboard a motorboat or multihull instead of a monohull sailboat?
22. How do we avoid/minimize aluminum corrosion?
25. How much does it cost to build a boat yourself, as you built Hawk?
32. What is the best way to attach the interior of a metal boat to the hull?
48. For hard dodger windows should we use tempered or safety glass and what percent tinting?
50. What do you think of spade vs. skeg-hung rudders?
51. What is the best paint strategy with an aluminum boat?
Also see:
200-mile days - 2005, Cruising World
For the sort of cruising we have done recently, Hawk has been near perfect, and if planning to do that sort of cruising again, we would build something just like her with a few minor changes. If doing less adventurous cruising, I would be inclined to think about something a little smaller (about 42'), which would be handier, less work to daysail, and less expensive. However, Beth really likes the water tankage, battery capacity and guest cabin that Hawk's size allows.
Hawk's hard dodger is absolutely brilliant. I am surprised it's not a more common feature on cruising boats. Hawk's superb upwind sailing ability has been invaluable on an east about/high latitude circumnavigation, but would be less critical on a more common milk-run sort of cruise (although still nice).
We have really liked the aluminum construction, which is completely leak-proof, extremely strong and rigid, yet easy to maintain and modify. All the fiberglass boats we have ever been on start to have deck leaks after two ocean crossings, as the fiberglass flexes and the stainless bolts through the deck (on stanchions, cleats and hand grips and blocks) don't flex, so the caulking pulls off the stainless. On Hawk everything is welded on, or bolted to tapped and welded on flat bar, so there are almost no holes through the deck and the boat does not flex at all anyway. All the fiberglass boats we have sailed in hard conditions have creaked and groaned as they flex, while Hawk is perfectly quiet down below in those conditions. The unpainted aluminum topsides are marvelous, as they take all the stress out of docking on rough docks or pilings. I don't have to worry about scratching paint or gelcoat if we bang them on something. The only two real downsides of the aluminum construction is that we have to use special (non-Copper Oxide) bottom paint, that can be difficult to obtain in remote ports; and the paint on the dodger and cabin trunk will develop small blisters after 3-5 years no matter how well prepped and sprayed originally. This does not cause any structural problem, just some extra maintenance work. I would consider leaving those areas unpainted if we did it all over again, but the white paint does keep things cooler in the tropics and Beth thinks it looks much better than bare aluminum.
Jakatan is a must read for anyone thinking about building a custom boat. This is a completely typical experience. There is minimal engineering content in the typical custom design and the owner & builder are expected to sort out the details. Top of Page
We both think cruising on a motorboat would be boring. We enjoy the challenge and effort involved in sailing. But we would not say "never". Specifically, we might consider one if we lived in the Pacific Northwest where the winds are very light and fluky during the summer, you absolutely need to be at certain current gates at a specific time and the distances can be long.
There is a 50' trimaran deigned by Nigel Irens that would be high on my 'next boat' list. However, Beth hates multihull motion offshore (it's jerkier and less predicable than on a mono) and does not think we need a 'next boat' anyway. Top of Page
We have had zero corrosion problems and have a good friend with a 25 year old aluminum hull who has had zero problems (he ultra-sounds the hull every five years to check plate thickness). My conclusion is that a few pretty simple steps will completely eliminate this issue:
(1) Use the right aluminum alloys – 5083 & 5086, not 6061 which is quite common but not very corrosion resistant.
(2) Use completely isolated hull/floating ground, so the hull is completely isolated from the electrical system – which means when we are plugged into shore power the hull is not part of the circuit.
(3) Use advanced plastics (UHMW/marlon/lexan) for all below waterline fittings.
(4) Pay careful attention to maintaining a complete epoxy barrier coat on the bottom. The French believe this alone will eliminate corrosion issues.
(5) Six large flush mounted zincs. The Dutch believe zincs are needed in addition to the epoxy coat.
(6) Avoid spending time in marinas, especially next to power boats (which for some reason tend to have bad electrical systems and suck lots of amps). We have a shore power circuit tester and a silver-chloride half cell which combined will tell us if there is any local electrical problem. Top of Page
If you do most of the work yourself (e.g. get a bare hull made professionally and do everything else yourself as we did) it ends up about the same cash out of pocket as buying a used boat and refitting it (to the same size and equipment standard) but with a lot more of your own labor in building the custom boat. However, with the custom boat, you end up with exactly the boat you want. If you have enough experience to really know what is important to your particular sort of cruising, you will end up with a much better boat for you. If you don't have enough experience to know exactly what you need, then getting a good used boat is probably better. In terms of time, it's quite possible to make the hull and decks in 4-6 months and the interior in 9 months, but to do that you need to keep focused on the job, not attempt impossible perfection, and hire experienced workers when necessary. Top of Page
Attaching the interior, especially the ceilings, to a metal boat is the most difficult part of installing an interior. The actual cabinets and bunks are relatively easy once you have the sole/bulkheads and ceilings in.
There are unfortunately no good books on this. The couple of books that are available are very sketchy.
The prime thing to avoid is screwing directly into the frames. This is bad for three reasons - first it's hard work to drill and screw into metal frames, second in an aluminum boat the screws (stainless) will cause the aluminum to corrode (and make the screws impossible to remove later) and in a steel boat you will break the paint film and cause a potential rust point, and third, in cold water/weather, the cold will be transmitted to the screw heads and they will form drops of water condensation which will stain the interior.
With a new hull or one that has not been foamed inside, the best bet for attaching the major bulkheads is to weld small tabs to the skin (say pieces of 3" x 3" x 1/4" at about 3' intervals around the perimeter of each bulkhead) and through-bolt the bulkhead to them. These tabs/bolts are then foamed over.
If the inside of the skin is not covered with foam, you will want to cover it at some point. Bare metal skin is very loud (wave slams sound like a drum) and also very wet (condensation). You can have someone spray foam it (it’s quick to spray foam but a messy job to clean the frames after a spray foam job) or glue foam sheets to it (lots of labor cutting the sheets to fit between the frames but no clean up afterwards). 'Normal' metal boats use 1" foam but high latitude boats typically have 3" of foam.
The main alternative attachment technique is to glue blocks of wood (epoxy covered/saturated to prevent them from absorbing moisture) to the skin and then screw the interior to these. If the interior skin has been foamed, you use a hole saw (say 3" diameter) to cut the foam, pry it out of the hole, and then glue in a similar disk of wood. Traditionally, people use 3M 5200 or a good polyurethane glue (like Gorilla glue) but Plexas has recently become the boat builders' glue of choice.
There are various modifications to this approach. Some people use various types of 'plastic' pads (usually phenolic or fiberglass) rather than wood, as wood can hold moisture against the metal which will create corrosion. However, wood should not cause a problem if it is truly epoxy saturated and coated. To get the most secure join, some people bolt all the pads to the frames rather than gluing to the skin.
A second approach is to install threaded inserts into the frames and screw the interior into these with machine screws, using stainless inserts for the high load attachments and plastic inserts for the lower load points. Done properly, this is an excellent approach but is very labor intensive and no boat yard will consider it. You put Teflon tape between the stainless threaded insert and the frames to cut the cold transmission and corrosion potential.
The approach I would use if I built another aluminum boat is to put the major bulkheads and sole in with the "welded/through-bolted tabs" as above, then lay-up a vacuum bagged foam core and fiberglass/kevlar skin all over the interior of the aluminum skin (just as is done in a cored glass boat), and epoxy the interior to that glass skin (again, just as is done in a fiberglass boat). I think this would be lighter/stronger/less labor than the more normal approaches I mention above, but I don't know anyone who has ever done it (I think because the metal boat builders and the fiberglass boat builders do not talk to each other at all). Top of Page
Although both safety (laminated) and tempered glass are considered ‘safer’ because they have been manufactured for strength and, if damaged, to not shatter into sharp shards, there is a difference both in the manufacture and performance of safety and tempered glass.
Tempered glass is a solid plate of glass and is found in the passenger and rear windows of cars. In the tempering process, the glass is heated in a furnace past its ‘annealing point,’ and then immediately cooled down with air jets. This forces the surface to quickly become cool and stiff, while the core of the glass, because it is still much hotter, takes longer to cool down and finally harden. This tempering process makes it about four times stronger than normal glass and if the surface receives any stress, it does not carry through to the core of the glass, so a crack is unable to form. If the glass does receive damage, it shatters into small cubes rather than sharp shards. Under wind pressure, tempered glass is approximately four times as strong as annealed glass. It resists breakage by small missiles traveling approximately twice the speed as missiles which break annealed glass. Tempered glass is also able to resist temperature differences (200 ° F - 300 ° F) which would cause annealed glass to crack.
Safety glass is usually constructed of two thinner pieces of tempered plate glass bonded together with a plastic layer in between them. This lamination holds the glass pieces together when it breaks. Laminated glass is normally used when there is a possibility of human impact or where the glass could fall if shattered. Shop front glazing and auto windshields are typically laminated glasses. The plastic inner layer also gives the glass a much higher sound insulation rating, and blocks 99% of transmitted UV light.
Both are completely acceptable alternatives. Tempered glass is stronger for a given weight, but safety glass will hold together if it breaks. I have been convinced that 10mm (3/8") tempered glass is virtually unbreakable (Oyster has used it for their big saloon windows and never had one break) and is the slightly better choice.
Lexan and acrylic are lighter, and shatter resistant so why not use them? Two reasons: (1) They both scratch and need to be replaced about every 3-5 years, even with the best anti-scratch coatings. Our glass is still perfectly clear ,with no special care, after 10 years. (2) They both expand and contract a surprising amount with the type of temperature fluctuations most offshore boats will experience. That will break the seal of any available sealant and they will start to leak. We started off with Lexan interior side windows and they started leaking after 4 years. We replaced them with 10mm tempered glass as the seal on the glass hard dodger windows were (and have continued to be) perfect.
The level of tinting represents a trade-off between heat gain during the day in the tropics vs. the ability to see at night. For reference, US state laws set a maximum amount of tinting (percent of visible light that is let through) for front auto windows. This ranges from 70% in 7 states (AK, CA, DE, LA, NY, PA, RI) to under 30% in 8 states (MN, AR, OK, TX, CO, SC, FL, WY). We ended up with 50% tinting and think it represents a good compromise.
All window films start with the film, of course, which is always polyester, 2 to 7 mils thick. Quite often, several thin layers of film are bonded together. One side is coated with either a pressure-sensitive or water-activated adhesive. The exposed surfaces of most films are also treated with a hard, scratch-resistant coating. To filter out ultraviolet radiation, chemical UV blockers (cyclic imino esters) are incorporated. If the film's purpose is to provide only UV protection and shatter resistance, no other materials need to be added. Some brands offer 'safety film' as the tinting base layer (see Lumar for example) , which acts like the plastic layer in laminated safety glass and might be the perfect compliment to tempered glass.
Then three different kinds of tinting can be added to the film: Dyed film, which acts by absorbs light/heat, and two types of metal tint which reflect the light/heat - Deposited film (a reflective metal tint that can only be done in a relative dark tint) & Sputtered film (can be done in any tint with almost any metal). In addition there are Hybrid film (combining dyes with reflective metals). The worst dyed window film can show signs of color fading in the matter of months under intense sunlight. The average hybrid type film lasts for 5 years, and the best quality metallized sputtered or deposition window film can last for a decade. We have a high quality hybrid film and it is still perfect after 10 years (I don't like the mirrored look of the pure metal films). Top of Page
We have done circumnavigations with each. Either will do the job but our preference is for a spade rudder. Most people assume we built Hawk with a spade rudder to maximize sailing performance (which it does), but in fact our main reason was because they make a boat much easier to steer in reverse. Our biggest concern with Hawk’s size was our ability to maneuver her in tight marina spaces and we wanted to make her as maneuverable in reverse as possible. Our experience with skeg rudders is they have a lot of prop walk and are not very responsive in reverse, while Hawk with her large spade is extremely nimble & responsive.
After living with the spade for a while we have discovered another big benefit, which is that it is very easy to inspect & maintain. It can be easily pushed out of the boat, the rudder and bearings inspected, and reinstalled, all while the boat is in the water. A skeg rudder is usually quite difficult to remove and the lower bearing difficult to inspect.
Many ‘sailing experts’ say that spade rudders are inherently weak and unsuitable for offshore use. This is flat out ridiculous. If you take the weight of a skeg and put that same weight into extra material in the spade rudder shaft and bearings you will end up with an extremely strong, essentially 'unbreakable' rudder. We inadvertently proved this by bouncing our spade rudder off rocks in Iceland for an hour. It held up to the abuse, maintained watertight integrity and the bearings were still within 2/1000 of specification when we measured them 10,000 miles later. With (full height) skeg rudders the lower bearing is often quite vulnerable to this sort of grounding. The plain fact is that you can build strong & reliable rudders of either sort or you can build weak and unreliable ones. It’s simply a matter of proper engineering and construction.
Too many modern 'offshore cruising boat' rudders have been engineered to meet only 'expected sailing loads'. A cruising or offshore rudder must be designed (and constructed) to survive full speed impact loads and not just sailing loads. The rudder on an offshore boat WILL hit stuff - from rocks to large sunken logs to containers. The rudder must be able to survive these impacts without catastrophic damage and still bring the boat back to safe harbor. This can be done without great difficulty, expense or weight, but the customer must make it a priority. The rudder (shaft & bearings) are normally out of sight and are common places for builders to save money and/or weight.
The proper engineering of a rudder is a sophisticated/complex task, but there are two simple things that an owner/buyer can look for in both spade and skeg-hung rudders.
(1) The rudder shaft should be large diameter as, at the expense of a little extra wetted surface area, this provides vastly increased strength in both shaft and bearings (a 10% increase in diameter can increase strength by 33%). So, it is useful to compare the shaft diameter of the boat you are considering with that of other well proven 'benchmark boats'.
(2) I think it is best if the rudder is all made from one material - that is all aluminum or all composite (carbon shaft, e-glass blade) or all steel (note: if the shaft is carbon, it needs to be engineered particularly strongly to handle impact loads without shattering - metal shafts are somewhat less sensitive as they are less brittle and can bend rather than shatter). That way, the rudder blade can be effectively sealed, there are no 'mixed materials' corrosion issues, and the shaft and blade can be strongly bonded/welded together. The common approach of mixing a stainless shaft and glass blade creates many problems - it's difficult to keep the glass sealed around the shaft so water leaks into the blade causing corrosion on the welds of the frames that join the shaft to the blade and crevice corrosion in the shaft itself. Top of Page
There are three separate issues with respect to paint. The first is that paint does not adhere very well to aluminum. Even the slightest imperfection in initial surface cleaning or the slightest scratch through the paint or contact between the aluminum and stainless fasteners will cause small bubbling/blistering and then over time these bubbles/blisters will grow. No matter how well or carefully done, to maintain ‘Bristol condition’ the topsides of a painted aluminum hull will require repainting about every five years. On the other hand, unpainted aluminum topsides are essentially maintenance free and remove a lot of stress from docking on rough/nasty docks because you don’t have to worry about scratching the hull. Thus the practical starting point is to leave everything above the boot-stripe unpainted. We find bare aluminum decks quite hot (on bare feet) in the tropics and we find non-skid paint to be much easier to touch-up/maintain than gloss paint, so we think it worthwhile to paint the decks in a light/cool color. Beyond the decks, where and how much paint you add is purely a matter of trading off bare aluminum aesthetics with paint’s maintenance & cost. I would leave everything else unpainted while Beth prefers the aesthetics of some white trim paint.
To have the best chance of paint sticking the longest possible period you need to do a very careful and thorough preparation job. You need to start with a warm, dry, calm day in a clean environment. The aluminum needs to be cleaned down to bare, shiny metal. This is best done by sand blasting or stainless wire brush abrading, because sanding often simply pushes grease and dirt around or into the metal. Then the metal should be acid etched and cleaned. and then the primer put on. The primer is ideally applied within 30 minutes of sand blasting, so the paint gets on before aluminum oxide starts building on the surface.
The second issue is with bottom paint. You need to put on a good epoxy barrier coat, both to give the antifouling something to stick to (it will not stick well to bare aluminum) and to help insulate the aluminum from stray electrical current. TBT antifouling paint was both very effective and aluminum-friendly but this has been banned for environmental reasons. Most current ‘yacht antifoulings’ contain a lot of copper oxide and these should be avoided, because copper connected to aluminum by salt water can create a battery and cause hull corrosion. Some people trust their epoxy barrier coat to separate the copper and aluminum. While we have not seen a case firsthand where this has created a problem, we think it best to avoid copper oxide if alternatives are available.
Copper thiocyanate is not supposed to damage metal hulls, and we have sailed for three years using this sort of paint. But our experience to-date has been that it is not that effective at preventing growth. There are a number of new anti-fouling paints with no copper of any sort (E-Paint is one of the leaders). We have not tried any of these yet, but we have gotten mixed messages from friends who have used these paints. We have heard from several people that one can of paint will work well and then next (same manufacturer/brand) will be completely ineffective, so either the quality control is poor or the paint is very sensitive to small changes in environmental/sailing conditions.
The third issue is inside tankage. Most aluminum hulls have aluminum tanks. Diesel can and should be stowed in bare aluminum tanks, but fresh water tanks should be given an ‘FDA approved for drinking water application’ epoxy coating. Top of Page
The short answer is that the ORC category 1 rules are a very useful reference when prioritizing safety issues/equipment (the 2008-2009 update has just been released). They have been written by experienced sailors based on the combined experience of the world’s offshore racing fleet. For the most part, we have taken this hard-won advice very seriously and attempted to equip Hawk so that she is in compliance with these racing regulations. However, there are a number of areas (21 in fact) where our experience and judgment have led us to reject the recommendations. The longer answer which details our approach in each of the 21 areas where we differ from the Category 1 rules. (Top of Page)
I have two quite different reactions when I hear this question.
The first keys in on the word 'need'. It's is amazing what some people have done with the most unsuitable boats. Webb Chiles sailed most of the way round the world in an un-decked open boat. Sr. Henry Pigott sailed round the world in a junk-rigged, decked-over 18' life boat. A Russian sailed round the world via Cape horn in an 10' sailboat he built on the balcony of his apartment in Moscow. Shackleton sailed a 23' open boat from Antarctica 800nm to South Georgia. A couple Italians sailed across the Drake Passage to Antarctica in an 18' beach cat. Several people have crossed oceans in life rafts and rowboats. So, the simple proven fact is you don't 'need' much more than a bathtub to do even extreme sailing. The skipper's skill, endurance and luck are much much more important to the success of any voyage than the vessel.
That said, we don't all have the skill, tenacity or luck of these skippers. The rest of us sometimes need a bit of help from our vessels. And that's true on any long distance cruise or passage. Our 'extreme' cruising in the high latitudes explains Hawk's heater and hull insulation but really have very little to do with why we built her so strongly. The one time we most needed her to be strong (when we went aground and bounced her rudder off some rocks for an hour) did happen to be near the Arctic circle in Northern Iceland, but we could easily have made exactly the same mistake in, say, Mexico. It was just a stupid error on our part, and could have happened anywhere anytime.
There appear to be about a half dozen boats a year in the North Atlantic below 40N which lose their rudders offshore, and these boats are typically well regarded cruising brands. I have no idea how many lose them in groundings, but it could be many times that.
Many people outfitting for this sort of trip buy a used boat and assume the structure is fine and dump a ton of money into watermakers and bread makers and such. Any trip offshore into ocean waves and strange harbors can be tough - the trips out to the Caribbean or down to Mexico are not cake-walks. When preparing for these sorts of trips I think it prudent to start from the most fundamental basics (that the boat is really strong and watertight and sails well) and make absolutely sure these fundamentals are perfect before investing in the extras. Most people don't want to believe it but even well known and proven 'strong' brands like Valiant and Shannon and Crealock, and many custom boats from well known designers and boat yards, have structural weaknesses that should be addressed as a first priority before spending a nickel of extra gear and gadgets.
What's so hard to understand for people not out doing it (or even those who have done it but then have spent several years back ashore - we do forget quite quickly), is how tough the environment can be. Taking a 'normal' boat offshore, even a 'strong blue water cruising' design, is like taking a stock jeep or pick-up on the Baja 500 or Paris to Dahkar races. The constant wave cycling and occasional skipper error will find each and every weakness. You will read that 'world cruising is fixing your boat in a series of exotic ports' but most people do not believe that will happen to them. But it will - the best you can hope to achieve is to make sure the fundamental components of the boat are sound so the underway repairs are an annoyance rather than a major safety problem. Even that is difficult do to the lack of engineering, low quality in most marine products/services, and lack of experience/knowledge in many marine 'experts'. We tried our very best to ensure Hawk's fundamentals were strongly & perfectly built, but even then we almost lost her rig and had to completely rebuild it to correct a manufacturing error by the (well regarded) spar builder.
When a friend of ours asked Eric Hiscock what he should focus on when preping a boat for a long cruise, Eric answer was "make sure it will keep the keel, rudder and mast in and the water out." When Ellen McArthur was near the end of the design process with Nigel Irens for her 70' trimaran, Nigel ask her if there was anything extra he could add to the design that would make her more comfortable, thinking (he has said) she might want a heated boot rack or something like that. Her answer was 'what would make me most comfortable is if I can be sure the boat will not break'. The greatest possible luxury for an experienced sailor is a reliable boat.
Net net, (1) you can safely cruise pretty much any boat if you have the right stuff and respect the boat's limits, but (2) for most of us, money should first be spent on getting the structural basics right, and these can't be taken for granted with even 'good brands' or 'name custom designs'. (Top of Page)
"The opposite of bravery is not cowardice but conformity."