Yacht Construction Q & A

Dear Steve, I have just read the glazing section for your FPB boat with much interest. Can you tell how the windows where attached to the aluminum structure? Many thanks, John H.

Hi John: We used a Sika system which included a primer first and then the "goop". There are very specific details on how this has to be done, environment, thickness of adhesive, etc. But it makes for a very strong bond.

There are a number of different companies who have systems for this. Regards - Steve

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(We just launched)...an Angelo Lavranos 43 (Barefoot) in British Columbia. It is unpainted. However, I was surprised to find a couple of deck leaks: One in an interior corner of a deck locker, one where the weld was apparently polished too far, and a burn-through where the genoa track flat bar is welded to the 3/16” deck plate. The builders are good welders so I was surprised by these. In your experience with unpainted aluminum boats have you seen this before on new boats? Regards, David

David: It is not unusual to have one or two things that are missed. Best way to fins them is with a fire hose. Once they are welded tight there should not be more problems. Enjoy your new boat! Steve

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Steve, First let me say I have appreciated the wealth of information in your books and website. Thanks!

In considering an aluminum hull for use primarily in the tropics and temperate zones, I was intrigued by your reference that on Beowulf you chose to use no insulation. You reference careful attention to the head and hull liners. Was there any attempt to provide insulation via the head and hull liners or did you just eliminate the insulation that would have otherwise been used and use standard liner materials? Also, you reference the reveals between the liner panels to promote ventilation between the liner and deck. Did you use a specific % of open space design spec, or just go more with looks? Given your experience in the tropics, would you go this route again, or use insulation? Anything else to consider if choosing to use no insulation?

Thanks for sharing your insights. David

The head/hull liners were from Ultaleather, a material which does not itself breathe. We left 3/4" gaps between the head liner panels and gape top and bottom of the hull liners. There seemed to be enough airflow that we never had mold or mildew issues and there was still some heat barrier from trapped air - at least we never felt inside heat in the tropics. That said, we also
had good awnings which were used at sea as well as at anchor. - Steve

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Good day, I am enjoy your site and also using as a reference source as I am presently having a 42' aluminum cutter built.

I was wondering if you have and could post a detail/close-up look at your stanchion/lifeline setup. There are several pictures on your site which show an overview and it looks like you used SS pipe going into aluminum pipe stanchion bases welded to the deck. One picture looks like you used SS pipe for some of the lifelines. I would appreciate any details you can provide.

Thank you for considering this request. Cheers, John

Hi John: Details of this are in our Offshore Cruising Ency under the aluminum details chapter. Basically we use welded alu. Pipe bases, with support of some sort (usually on a frame) and then stainless stanchions. A plastic isolation sleeve is used between the two metals. Most of our life line stanchions are 30 to 32" in height and are of 1.25" diameter medium wall pipe. Regards - Steve

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Hi Steve, I am looking to buy a plan of a sailboat with between 38 & 40 feet with small draft (1.20 to 1.40 m). I know Hartley boats but I would like to contact other designers that have plans to be made in Ferrocement. Do you know any? Best Regards, Eduardo

Hi Eduardo: I don't know of anyone doing Ferro boats these days. Our advice is to use a different material, of you are going to custom build. The hull is only 20% of the total cost and ferrocement is not a good material when you are aground. There's a section on materials, and ferrocement in our Offshore Cruising Encyclopedia. Regards - Steve

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Hello from New Zealand, We are a 40ft aluminium sailboat called Wyndeavor. We've sailed from the Pacific Northwest to New Zealand with our two kids and have recently put our boat on the market. The paint on our boat was chipping terribly so we decided to go with bare aluminium in order to help the boat sell (low maintenance). We recently had the boat sandblasted and are not too happy with the outcome. We have covered most of the deck with a nonskid product (Treadgrip) but the rest of the deck and hull to the waterline are bare. The bare aluminium is very rough and our feet and fingers leave marks. We understand that you have a lot of experience dealing with aluminium so we were wondering if you had any advice regarding these issues. Should we sand the decks? Will it get better as the boat oxidizes? Should we just leave it be? Can you help? Regards, Kelly

Hi Kelly: Yes we do have some experience, in fact exactly the learning curve you have gone through! Our first unpainted boat was sandblasted. Moving if from the build shed to the water it was marked by some tree branches and I realized we'd made a mistake. The concept is to be easily able to refinish a rough spot, which means grinding, not sand blasting. So, we ground off all the expensive sand blast finish!

For the deck, the nonskid material, as long as it gives you a good foot hold, is the best approach. Otherwise, what we ended up doing on Sundeer was using the edge of a cut-off wheel and grind the decks to put a tooth into them. But a good plastic tread would give better traction.

The sandblasting leaves a porous finish, and until this naturally oxidizes, probably four to six months, it is going to show more things like finger prints. I am not sure why, but the smooth mill finish, or a ground finish with heavy Scotch Brite pads seem not to have the same problem.

Seems like you have two options. Stay with what you have for now. Or get out the grinder and lots of Scotch Brite and go to work. Beowulf, at 78', took about 80 hours to polish the topsides, grind the decks, and polish the coamings.

Good Luck with whatever you decide you do - Steve

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Hello Steve & Linda, I just watched Offshore, and enjoyed it very much. I have been looking around on your website, and I think it is fantastic. Well done. I dream of having a lifestyle like yours one day.

I'm 22, and have a 34' custom riveted aluminum round bilge, Terhou, built in England in '59. Within the next decade or so, intend to weld something bigger (and faster) for myself.

This goal has me thinking about design, best practices, etc. You mentioned in Offshore that Sundeer's keel is welded on. How is the ballast installed? Is it poured inside? I assume it is lead? - Ryan

Hi Ryan: Our normal practice has been to weld the keel on. Some times the lead is poured into the keel before welding it to the hull and sometimes the lead is poured after.

In the case of Beowulf, the keel was fabricated, lead poured, and then after she was delivered to her launching point on a truck the keel was welded in place. Steve.

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Good Morning Steve: I have a 98 Valiant 42. I'm selling her and moving to the trawler mode. Most trawlers are just ugly--too high off the water, too much windage. I've found the Dieselducks designed by George Buehler and built at Seahorse Marine in China. Please look over these and let me know what you think. Here is their website: http://www.seahorseyachts.com/ Go to the dieselduck 44 and take a look at them. Please let me know how you feel about steel boats and if the design is sound. I respect your opinion more than anyone out there. Thanks again, Roy

Hi Roy: I would take extreme care with buying a boat in China, as there is little legal redress in case of a problem. First, I would use a letter of credit for the full contract price, with the exercise of the L/C based on your acceptance (usually with a surveyor involved). Second, make sure the specifications are detailed, and cover everything you expect and how it is to be accomplished. The price sounds very attractive, so there's some room for cleaning up problems, but you want to be sure the basic boat is sound. There's a lot of detail on this subject in our Offshore Cruising Encyclopedia towards the back. If you go ahead, let us know how it turns out, and good luck. - Steve

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What do you consider the best material for pilothouse windows? Lexan, Tempered or safety (laminated tempered) glass?? Phillip

There are no silver bullets - any of these materials will work. You need to calculate the hydrostatic pressures as a start, and then the spans involved, which will lead to the thickness of the various materials required. Easy engineering for anyone familiar with the process. - Steve

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Dear Setsail, I'm in the process of speccing out the glazing for the pilothouse on the boat I am building. I have narrowed it down to either 1/2" tempered glass or 1/2" abrasion resistant polycarbonate and am now looking for a little real world experience to tip the scale. One nagging doubt: the long-term durability of this product in the voyaging environment. I've read in your Offshore Cruising Encyclopedia that you recommended and used polycarbonate on your sailing vessels, but noticed that you made the switch to glass in the FPB series. After walking the docks at the boat shows and talking to designers and builders of some of the high-end custom pilothouse and raised saloon boats, it seems they all are going with toughened glass, but none seem to have any direct experience with abrasion resistant polycarbonate. What's your experience? Best regards, Collin

Hi Collin: We have used Marguard, a coated polycarb by Lexan, for many years in our sailing designs, due to its lighter weight and impact resistance. However, the most you can expect is five years, and if any petroleum-based cleaners are ever used on it will be ruined. So, you do have to be careful with it. There are installation details in our Offshore Cruising Encyclopedia.

The FPB has larger spans, so we would have had to go to 25mm polycarb, not practical for a variety of reasons. Also, this design is not as weight- or center-of-gravity-sensitive as our sailing designs. Regards - Steve

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Hello! First let me just say how much I appreciate your books, your designs and your web site. You really are unique!

We are starting to seriously think about "getting off"and I therefore have a lot of boat design features to sort out.

I hope you can help me with these two:

Storm shutters. How did you deal with storm shutters on the Sundeer series? I think about the large windows in the hull and the "pilot house". Are storm shutters used or are the windows simply designed to be "storm proof"?

Insubmersibility. What do you think about insubmersible boats, or modifying a boat (injecting foam in interior spaces that are not used for example) so that it becomes insubmersible? I have seen your comment on the Yacht Saver, but this seems like a costly and technically complex solution (just another thing that needs surveys and that will malfunction when it is needed). Another thing is the problems with large balloons inside the boat in a crisis situation.

I hope you will take the time to answer these questions. With regards, Erik

Hi Erik: First, the pilot house on the Sundeer 64 is really a permanent dodger. There is a waterproof sliding hatch into the interior, so the pilot house windows are not part of the water tight integrity of the boat. There have been many circumnavigations done in these boats and I have not heard of any problems. But in a roll over you would expect that large house to go - or at least to lose some of the windows.

Built-in floatation is very tough to achieve in a true cruising boat because of loss of storage and tankage volume. We think it is better to have watertight bulkheads, strong keel structure, and extra laminate in the collision areas. Regards - Steve

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Hi Steve, Absolutely the best investment I have made before going full time cruising is your Offshore Cruising Encyclopedia. However I am hoping you can elaborate on one small statement that I keep coming back to, and it has a major bearing on the type of yachts we are looking at purchasing. As you're aware, there are many more fibreglass boats to choose from, even in the South Pacific where steel is reasonably popular choice. Which seems to confirm your statement that "on average 1 in 12 yachts that spend more than 2 years in the South Pacific basin ends up on a reef permanently". As I am looking at the South Pacific, the Great Barrier Reef, and the archipelago of Western Australia's Kimberley Coast - much of which is still not charted - as the areas we most wish to spend our time. I had resigned my looking to steel or aluminium yachts, however I have found a strongly built balsa cored 40' cruising yacht that I particularly like, but I keep thinking about those reefs and rocks. Any more information you can give me or direct me to in helping me make a decision on whether to buy this yacht or keep looking would be very much appreciated. Regards, Peter

Hi Peter: There is no easy answer to your question. It comes down to weighing the risks. Some folks feel that with GPS, the risks are less. But charts are not any more accurate in the good cruising than in the olden days. Where GPS helps is in enabling you to follow a track out that brought you safely into port.

That still leaves the risks of getting into port in the first place, and the odd mistake which we all make.

My own personal preference is metal. Not only is it better with mistakes, but if the boat is done correctly you won't have to worry about leaks.

Having said that, one of our Deerfoot 2-62s took on one of the Tuamotus some years ago, spent a week or so visiting on the reef, and then was towed off by a commercial salvage vessel. Her GRP for the most part came through unscathed - but there was some damage that would not have been there on a metal boat. And she spent quite a bit of time in New Zealand being repaired.

The vast majority of cruising boats are GRP - and if the boat is well built, and you are prudent, you will probably be OK. But sometimes things go awry with the best laid plans - or a neighboring vessel starts a chain reaction in a crowded anchorage. In which case you would rather be on a metal boat.

I know I have not answered your question - there are no easy answers as I said in the beginning. - Steve

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Hi Steve Any suggestions for a leaky goit deck hatch (the one under the vang)...thinking of putting some wet suit neoprene in the gasket...Very annoying, Phil

Phil: If it is the old-style cast hatch - which are very good - it could be the seal between the hatch and the deck, or the seal on the hatch itself. For bedding the hatch, your idea of wetsuit material is excellent. This is what we've been doing for years on all deck hardware. Otherwise, you need to replace the hatch's gasket between the opening faces.

One thing which helps is to have breakwaters around hatches, in your case from teak, so they don't get hit by wave impact. This is standard practice for us also.

If you have a copy of Offshore Cruising Encyc. aboard there are some photos of breakwaters. - Steve

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Hi Steve, What do you use for deck fills on an aluminum deck? Are the Marelon fills a good choice, or aluminum (Wilcox-Crittenden) welded on? Could I just weld in pipe with threaded ends and put a cap on the outside (keeps the opening off the deck)?

Also, would you let bails for halyard/reef blocks through the deck and weld top and bottom, or do you think there's enough strength in a fillet weld to hold it on the deck? Best, Alex

Several answers: First, we usually do not weld deck fills as there is a chance they will distort - unless you can find some very beefy ones, which will stay round. The capped, threaded pipe idea is the best, in terms of eliminating leak potential, getting the cap off the deck where it is less vulnerable to water ingress, etc. Only issue is if it is in the way of running rigging, toes, etc.

As far as running rigging blocks, and how they are welding, this is a function of the amount of load, load path, and deck thickness. Generally, using 4mm plate, we weld on top only, but we gusset to make sure no bending can occur of the load path is other than in line with the tang. Steve

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Dear Steve, I have bought Your Cruising Encyclopedia & Mariners Weather Handbook from Captain Watt's in London. I can only say they are a great life work's to make a boat owner's life easier with the right kind of knowledge - thank you. Also I met the owners of Condor while they were in Sydney Australia a few years ago - Skip and his wife. What a lovely couple and boat they had built in NZ to your philosophy and design.

I own a 50' ex BOC open class yacht build in 1986 called Skoiern IV. She is built from aluminum. Because of the problems of toxicity today's available anti-fouling are not effective without the tin content. I'm considering using a UK product called Copper Shield, using first a coating of epoxy as a primer to protect the hull, then apply the Copper Shield, which is a copper-rich anti-fouling that does not require redoing for ten years plus. My fear is the risk of using copper on an aluminum boat - is it safe? The company said yes it is. Since I would like to solve this problem once and for all, I'm inclined to try it. but I don't want to find religion with a holy boat...I look forward to your comment, as I will need to redo the boat's bottom soon. Kind Regards, and keep up the good work. - John

Hi John: Copper bottom paint is OK as long as there is an intact barrier, made for the job. Many of the commercial boats in the States are using a system which includes a barrier coat which acts as an anode, so the anode coat is used before the aluminum, in the case of a bare spot.

The main issue is to make sure the barrier coats are properly applied, are the correct thickness, and that the total paint system is from a single source with a history of this type of work - you do not want to be an experiment for them!

And then, when the bottom paint is abraided, and bare aluminum shows, when you repair this, you have to be sure the build-up prior to copper-laced paint is done correctly.

If you go this route let us know how it works out. - Steve

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Linda/Steve, You are the woman and the man! I am building a 46' aluminum Radford R14 pilothouse. Your specs on the FPB 83 note 1/2" Armaflex insulation on the hull - why not thicker insulation? Does your choice of Armaflex usher in a product that will become the aluminum boat standard insulation? Appreciate your reply. - John

Hi John: The question of insulating an alu. hull is complex. Here are our considerations:

1-As Linda is allergic to mold and mildew avoidance of these is the #1 requirement.

2-Sprayed foam absorbs water from the air and over time loses its insulating capabilities, in addition to which it is a great mold factory. Also, the foam continues to release unpleasant gases throughout the early years (or more) of its life.

3-We chose Armaflex because it has the lowest moisture absorption rate we could find. It is also very good on noise attenuation.

4-The 1/2" (12.6mm) thickness was chosen as it eliminates condensation down to about 20F at a 65-degree F interior temperature at a humidity level we think we can achieve. This is below where we ever expect to operate the boat.

5-More insulation would probably be warranted for colder climates, but for our purposes, when we looked at the heat load differential between 1/2" and 1", it did not warrant the extra cost, weight, or installation hassle.

6-We are using 1" material in the engine room for noise control. 2" is used on the watertight bulkhead into the interior.

7-We expect there to be a slight cost premium compared to a sprayed foam system, after taking into account clean-up costs with the foam.

Hope this helps - Steve

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Steve, Hope all is well and everyone is healthy. Richard and Kati have been keeping me apprised to your progress on your latest. Best of luck with it! Do you have a launch date?

As I'm insulating my sailboat, I find that I need a flexible insulation in some areas. The semi-rigid just will not work well!

Richard said that you were using scuba wet suit material. Great idea! This would work well for me several locations against
the hulls sharpest curves...behind the nav station, a few lockers, under vanity, etc. So, were can I purchase this material ??

Thank You and Good Luck, say hello to Linda. - Michael

Hi Michael: We are using a material called Armaflex. They have local distribution around the country. The URL for the website is below:

http://www.armaflex.com/www/armacell/armacell.nsf/ansHTMLSeitenLookUp/US_Frame?OpenDocument

Regards - Steve

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We just purchased an aluminum boat. It is primed and painted with bottom paint and reg on the top sides. It has about 7 anodes on it.

We have two choices to keep the boat this summer, one has steel docks constructed of steel drums held together with steel structure covered with wood. This is all held with steel chains. The other location has concrete main docks and aluminum finger docks.

The problem is we like the community at the first as the second is a municipal marina and has little charm.

I have read about electrolysis and all that stuff, I am planning to hand Zinc anodes over the side in either case.

What are your thoughts/suggestions? Thank you. Don

Hi Don: Congratulations on the new boat!

The issue is the electrical potential between the boat and the dock. As long as you are isolated electrically, you are OK. The biggest issue will be your shore power cord. Make sure this is done correctly, and that you have an isolation transformer in the circuit on your boat--so that you are isolated from the shore earthing/grounding system--which will also include the steel dock. - Steve

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Steve, I have a chance to pick up a 53' Ferro cement sail boat. It needs to be finished out with masts, paint etc. Do you have any input in the Ferro cement design. It was built in Alaska, nice lines and quality hard ware, new Volvo engine, all oak inside. I can not see any rust leaking through the cement, it is in a boat yard and has been there for 10 years. It has not sailed. Please give some input if possible. Cheers, Spike

Hi Spike: Tough question. If properly built and if you do not make mistakes with the boat--both big "ifs" ferrocement can be OK. However, it does not have the impact resistance of FRP, or metal (or even wood) and if you put the boat ashore, or in some cases even have a moderate grounding you have a high risk of major damage.

A second issue is insurance. It is sometimes difficult to get insurance on ferrocement boats.

As a result of the above, ferro boats typically sell at very low prices--which makes them attractive. You just have to be realistic about the risk factors inherent in the material. Steve

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Hello, Thanks for both the Offshore and Seamanship: both were great reads. The website is always good for a bit of day dreaming as well as loads of info. Keep up the good stuff!

I'm currently looking into purchasing a smaller (27ft) Dutch classic to enhance sailing, tech and nav skills on coastal North Sea before following the big step dream.

I've located a Trintel 1a - in steel and a Trintella 1a in GRP, essentially the same design, both from around 1971. I'd go for steel for security; but the problem is that the steel version is about twice as heavy, still, I'm a bit hesitant about "old plastic"; I've read about osmosis, but have no idea what it looks like. Could you give me any ideas on what to look for?

Thanks very much, Eltjo

Hi Eltjo: Easy question first--any qualified surveyor can check the fiberglass laminate for osmosis and/or water intrusion. The odds are if the boat is that old, and does not have problems, you are safe in the future. And if it has problems, you will find them (or they were fixed in the past).

Regarding steel Vs fiberglass--in a boat of this size it is a tough comparison due to the weight issues, as you have pointed out. The extra weight compromises boat speed,and in some cases capsize resistance, unless the vertical center of gravity has been kept the same. My instinct would be to go for the fiberglass, assuming it is structurally sound.

Good luck--Steve

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I just ordered a J-BOAT J 109, and would appreciate your opinion about the possibility to improve the security in terms of buoyancy if...I learnt that inflatable buoyancy bags are not currently available; to my knowledge the only builder Yachtsaver is not still on the market. Another solution for this boat would be to transform the door between the forecabin and the saloon into a water pressure resistant door, such as in boats like the Maramu by Amel. This solution is not perfect, but, since the main risk is a frontal collision, it may be a significant point. In my opinion, at sea, a door must be open or closed, and the forecabin is not usable in practice. So, at sea, this door can be closed. How to get something efficient, light, and safe? I wonder if a device such as a timbered safety door, as those for theft protection would be the solution. I am very interested in your analysis and I would be grateful if you could help me. Yours sincerely, Alain P

Hi Alain:

At a minimum I would have a forward watertight bulkhead for collisions, and a second one, at the aft end of the boat to protect from rudder/prop support bracket problems.

Watertight doors are not difficult. Just somewhat heavy, and costly. But well worth it in terms of security in my opinion (all of the boats we've designed and built have been fitted with fore and aft watertights). Regards--Steve

(SetSail note: Yachtsaver is back in business. Click here for data on how to reach them.)

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Hi, I am planning a circumnavigation and am in the process of buying the appropriate boat as large as possible for two to handle. At the moment it looks like an X-562 will fit our needs fine. It can be delivered with a 2.8m draft and a 2.5m draft. I am going North Europe-Canaries, West Indies, Galapagos, Fiji, NZ, Australia, India, Red Sea. Can you give me an indication of the draft which in your opinion allows us to go the most nice places on the route?

Hi Mogens: Draft is the toughest of all questions. This really depends on your tolerance for risk, faith in charts, and desire for performance which in itself is a safety factor. We sailed around the world with a draft of 2.3m (7'2"). But when the time came to do our next boat, we dropped her draft to 1.85m (6') because we wanted to be able to cross river bars in the event of a hurricane to seek protection in the mangrove swamps, and we'd had some very close calls with the first boat where a little less draft would have made a lot of difference.

Today we have 2.4m (7'9") draft--but this is on a 23m (78') boat. In your own case, the extra 0.3m (12") of draft would really help performance. But there are some areas in Australia, and the Indian Ocean/Red Sea where the extra draft might be the difference between safely crossing a shoal and running aground. If I had to make the decision myself, I think I'd go for the shallow draft fin--and give up the performance to windward. Steve

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Hi Steve, You built some 74' Motorsailors that are illustrated in the Cruising Encyclopedia, but not mentioned anywhere else that I can see. Can you tell us more about your Motorsailors. What are your current thoughts on Motorsailors? What IS a Motorsailor? BEOWULF is sometimes referred to as a Motorsailor and may be the best example of the breed. John T

Hi John: Yes, we've done a series of what we refer to as motorsailors--basically all of our boats since the 74' Deerfoot ll (including all of the Sundeers). In our definition a motorsailor simply has a bit more horsepower and a more efficient prop than would otherwise be the case. There is also a slight difference in the distribution of volume in the hull. Since the Deerfoot/Sundeer types power very efficiently, this is not to hard on sailing performance--just a slight penalty in light air sailing speed when the engine is on anyway on a cruising boat.

Re BEOWULF, when we called her a motorsailor it was a bit tongue in cheek. However, she does power at 10 to 12 knots, depending on wind, sea state, fuel management, and how antsy we are to get to our destination. Our recent trip from Panama is a good example--13 days from Balboa to San Diego (plus a couple of days waiting out weather). We got in about a day and a half of sailing--the rest was a very pleasant power boat ride. Steve

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Dear Steve and Linda, heaving read all of your books I would like to thank you for your advice given there. As only one example, we've changed our mainsail to an extra-roached, fully-battened one which gave us 1 knot extra speed at all courses, which is a lot for 34 feet. Having a double backstay we don't see any problems even with 30 cms overlap.

My question now is: What do you think of centerboards? We are interested in a 43' Dutch aluminium Koopmans design which has no keel whatsoever. She sports only internal ballast and the centerboard seems rather small (weighing around 400 kg). The boat was constructed for falling dry in the North Sea. She has a long waterline and a draft of 1,20 meters board up and 2,50 m board down. The rudder is fully integrated into the hull and in line with the ship's bottom, more just like a motorboat. Is the rudder surface of approx. 1,2 squaremeters large enough and the profile (not balanced) effective to steer the ship in a heavy going?

Thanks for some advice, and have some fun with your grandbaby. Andreas

Hi Andreas: Those are hard questions to answer without seeing the lines of the boat. In general, centerboard boats, especially those without stub keels, depend on a wide beam for initial stability. Wide beam will make the boat harder to steer in general, and it will develop weather helm more quickly with heel than a narrower boat. The unbalanced rudder will also be harder to steer. On the other hand, the shallow draft could be a big advantage, depending on where you are going to be sailing. For heavy weather I prefer a narrower boat with a fin keel. Steve

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Hello, I'm looking at purchasing a yacht capable of offshore voyages in and around the Southern Ocean, I have found one which suits all my requirements except this steel yacht has a wooden deck and cockpit. Would this partial wooden construction compromise the structural strength of the yacht given worst-case scenarios in big seas? Marcus

Hi Marcus: Ideally, you would have all metal construction. This will have less of a tendency towards leaks, and ultimately be stronger. On the other hand, there have been lots of steel boats built with steel deck frames and timber decks. These can be quite strong, if properly done--but it must be well executed, and any openings in the deck and/or hatches carefully designed and fastened. It all comes down to price, and how the boat you are looking at is executed. All other things being equal, I would prefer all-metal construction. On the other hand, properly executed, I would not hesitate to go offshore with a timber/steel composite structure. Regards--Steve

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Hello Steve, I have been offered a really nice bare hull, but the mould for the deck is a center cockpit. I would like to build the boat as an aft cockpit. I could either build a deck in plywood and glass it on top afterward, but I wondered if I could build a deck in aluminum. This seems to me to be quite a good mix. Fiberglass below and aluminum above. This would suit me because I could leave it bare for non slip on the side decks and also I could build the hard dodger in aluminum. Do you think that the differential expansion between fiberglass on aluminum could cause a problem? I also wonder whether it might cause problems later with resale because it is so unconventional. Any comments would be welcome. Thanks, Howard

My suggestion would be to do a "plug" in light plywood and then do a one off layup in fiberglass. I say this because of re-sale, and my guess is that it would be net easier. Good luck--Steve

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Dear Steve & Linda, It was only yesterday that I was pointing BEOWULF out to some of my sailing students ( I'm a part-time instructor) as she came into Marina del Rey and backed into a berth at Cal YC; it prompted me to make a visit to the Ship's Store and part with some $'s to purchase a copy of Practical Seamanship, in which I have had my nose firmly buried ever since. Thanks for creating such a practical, logical and well-written tome; it will help make me a better, more rounded sailor and instructor, and aid in passing on my knowledge and experience to the new converts of the fine art of sailing. Perhaps you might clear up a question I have. It seems that I read somewhere that BEOWULF has only 1 (one) thru-hull. Is this so? And if so, where can I find some info on how you managed to achieve this seemingly impossible feat? I must admit I have spent some time thinking about it and am somewhat baffled. I look forward to reading and owning some more of your titles in the future. Thanks, Paul G.

Hi Paul--It is true. One incoming salt water manifold, and two standpipes--through which all pumps discharge. This approach has been standard with us for many years. It does force you to pump out sinks, but that is a small trade-off for the security of one through hull. Steve

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My basic question to you is in regard to my sanity along with that of my wife...We are dreaming of sailing, selling the house, sticking a chunk of money in an untouchable fund (for our eventual return in 10-15 years) and launching. But, we don't just want to buy some fiberglass yogurt container for our trip. That would not fit our style. We want to build our yacht ourselves. I do have an engineering degree (although I have not used it) and an MBA (definitely a negative). My wife is a graphic artist with experience in interior design. Well, here is my plan. Is this do-able??????

1) Create detailed specifications and drawings of what I want. I am 50% there now after many drawings. (FYI: 55'-65' modern aluminum hull, deck to include a classic pilot house and a sloping sheer line, modern schooner rig with marconni aft and gaff fore sail. Fore and aft cabins, bulkheads fore and aft with a water-tight, center, engine room. It should have a fin keel and a skeg hung rudder. Goal: Long-range, comfortable, easy-to-sail, high-safety factor, classic looking schooner built with modern components.)

2) Hand my plans/specs to a qualified naval architect/engineer to create the actual designs. IMPORTANT: Architect should have proven ability to produce complete "CUT" files for all Ribs, Stringers and Hull Plates. Complete hull.

3) Have these "CUT" files delivered to an Aluminum fabricator in the Austin/Houston area for CNC cutting.

4) Deliver these "puzzle" pieces to my enclosed shop for build.

5) Use certified welders (myself included), friends, family and an experienced boat-building consultant (can be remote) to assemble the hull.

6) Select components and build-out the remainder of the yacht using friends and family. Did I mention budget...Can I get the DESIGNS with CUT files under $20K??? My hopes for the entire project cost would be in the $150K range. (tools and facilities not included) I see that you have used experienced boat yards for all of your builds. Even with your experience you choose to leave the assembly to others. So, am I attempting something that I shouldn't? I don't think so, but then again, I have never build a boat before...other things, but not a blue-water home for my family. Any advise, suggestions or a sanity check would be greatly appreciated. Sincere Thanks, Andy

Hi Andy: There is no way to do the project for close to what you are hoping. The materials "buy" alone, will run from $200,000 to $400,000 depending on what you chose and how you do it. If you were a professional, no learning curve involved, the hours to do a custom boat of this size would run anywhere from 16,000 to 24,000--depending on fit and finish. A quicky job, with a basic hull and let's-camp-out interior might save you half of this in time. But then you could never sell the boat.

Note--the metal work in the boat represents about 22% to 25% of the total project. And of the metal part of the build, the basic framing and plating, and welding thereof is about half of the metal part--the other half is in the details like tanks, mast steps, rudder, chainplates, deck hardware, and a thousand other details.

Boat building is a disease. If you really have it, then the best thing to do (aside from shooting yourself) is to buy a used boat, fix it up, go cruising for a year or two, and then come back and build your dream boat. Otherwise, 70% of the decisions you make now--and there will be thousands--will be wrong. There is no way around this--you have to get experience. Designers won't be able to help because 95% of them have never lived with their boats (and racing/passages only partially count in the decision-making process).

Sorry I could not be more encouraging--but I want you to have it straight. Boat building is a very tough business. Final thought--after you've got experience, find a location in the world where there is good productivity, and low wages vs the $, and build there. Good Luck--Steve

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Greetings to you from Vanuatu...We are leaving Paradise in December to return to NZ to find a boat to go cruising for the next three to five years. All going well, we will do a circumnavigation. We are interested in steel boats and I was wondering if you could recommend the best book I could read on steel construction techniques--with a view particularity to proven or recognized standards. Also, do you know of a good steel surveyor in Auckland who could give us an opinion on one boat in particular that we are interested in at present. The reason I ask is because we have had several opinions so far and they are all conflicting!!! Many thanks for your help. Keep up the good work! Gary

Hi Gary: I don't know of any books on steel construction per se. However, you might check with the big boating book store at the bottom of Westhaven (name escapes me right now). I don't think there is any "ultimate" way to do things with steel. There are many approaches to framing and construction. The key factor is to make sure no water can get trapped in the structure below decks (good drainage) and that there are no rust pockets in the structure. You can always ultra sound a hull to see if it is OK, and cutting out and replacing plate is no big deal. If you look at a bunch of steel boats--crawl through the bilge's and engine rooms, look at paint finishes carefully, and be mindful of the detailing on deck after a while you will know what is right and wrong with a given boat. However, our personal preference is aluminum. Lighter, easier on maintenance--especially if you leave it bare. Good hunting--Steve

A reader writes:

Hi, I was surfing your site looking for some input on steel boats, and I found a question about books on steel boats (Cruising Central/Cruiser's Q&A/Construction issues/Steel Boats). There was none mentioned. So I thought to send you this one I came across for future reference. I have not read it yet but the author is a known metal boat designer. Title: Metal Boats (description from http://www.bruce-roberts.com/ "By Bruce Roberts-Goodson Written for those who are interested in building in Steel, Aluminum and Copper- Nickel. The benefits and disadvantages of the different metals are explained in detail. Discusses the right tools and equipment and welding techniques and how they apply to various metals. The differences between the various hull shapes is explained in detail plus selecting the correct engine(s) and equipment. Other subjects include electrolytic protection, building skegs. keels and pilot houses, in fact everything you need to know about metal boats is covered between the pages of this book. ") Best regards, Lycio, Rio de Janeiro, Brazil

Another reader writes:

One of your readers asked about steel boat information. I am rebuilding Minots Light, a steel 58' Alden Ketch. During this project I have found a source for information about aluminum and steel boat construction, repair, system management, and maintenance. to be helpful. The Metal Boat Society maintains a website at www.metalboatsociety.com. There you can find tons of information to sift through. Neophytes to experienced professional builders contribute info/opinion/ideas at this site, sometimes sparking spirited debate. P.S. After much soul searching, researching, and penny pinching, I am now the proud owner of a Hundested CPP. -Robert Lanford

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Giving us most headache in the construction plans for our yacht at the moment is the heads and holding tanks. I have read all your books now and a few others and we will follow your advice, make it as simple as possible. Now there are a lot of heads on the market and the next one is always better than all the others. Please point out one head that you know works and that you have experience from and is simple in construction. I want to pump from head to a holding tank and then be able to choose either pumping out to the sea or to empty the tank at service stations where available. Thanks for your time and all the best to all of you at Set Sail.

Hi Chris: I have limited experience with head, having found several that work and having stayed with them over the years. For simple, light,and inexpensive it is hard to beat Raritan's PH2 (or at least that is the model we last used).

For long term cruising I would suggest carrying a complete spare pump, and half a dozen "choker" valves. We have also had very good luck with Mansfield Vacuflush toilets. These work well with holding tanks as they have a very small a amount of flushing water. Carry a "plunger" in case a guest uses too much toilet paper and plugs the system).

Note: Vacuflush should be used with fresh water (you can use salt, but it causes a build up of minerals in the pumps and vacuumed chambers). Steve

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Recently a builder of fiberglass boats said that aluminum as a hull material is way inferior to fiberglass because:

1. Aluminum suffers from fatigue--the older the boat the greater chance for structure failure.
2. Aluminum boats are prone to failure by stress corrosion and weld corrosion.

Based on your research and experience, these statements seem to misrepresent scientific fact. In your book, Offshore Cruising, your thoughts are very clear about the superiority of aluminum for cruising boats. We would be interested in your prospective on items 1& 2 and what the best welding process is for aluminum hulls. Thanks, John and Ruth

Hi John and Ruth: We swing both ways, as you probably know--we do aluminum and fiberglass--and have experience going back 22+ years with both. Both materials can be long-lived, if done properly, and both can have problems if not done correctly.

Regarding the specific questions raised:

1. Fatigue is an issue with all structures--FRP and Alu. This starts with the material choice, how hard spots are handled, and the usual general engineering approaches. We have always used the same philosophical approach with Alu. and FRP, and have seen no difference in the longevity of the two materials.

Regarding the risk of fatigue in older boats, as long as the aluminum is properly engineered, I do not think this is a major issue. Certainly no more of an issue than with fiberglass--where you also have to be concerned with osmotic blistering, interlaminary shear failure, etc.

2. Stress and weld corrosion can take place with any metal--and can be particularly severe with stainless steel. With aluminum, the main issue is proper welding wire and proper welding environment. Where there have been weld problems, in our experience these have shown up during manufacturing, and the contaminated welds have been cut out and re-welded. In our experience this has not been a problem associated with age.

3. I'll mention a third issue which your FRP builder did not--galvanic corrosion. This can be a major problem with aluminum and steel hulls. But only if they are not correctly wired. However, it is certainly less of a problem than osmotic blistering in FRP. Once again, in our own experience we have not seen problems with galvanic corrosion. Steve Dashew

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Dear Sir, We plan to build an aluminum catamaran (sail) 47', with round, relatively narrow (4') hulls. We have several good alu-motorboat builders in the region--however no catamaran built here except the Osram IV which is a chaine hull. One builder would like to build the boat, if I would roll him the plates, one hullside 4x12x 8 1/4 or 3/16--He is welding nice motorboat hulls, nice seams etc... but how do I form the plates? I found one large rolling machine, but it's outside and the rolls are very, very rusty ... and what about the next step to get the compounded curve? I read about the English wheel, but that's good only for steel, because the tracks are on the outside. The necessary (local) expansions of the prerolled aluminum sheet are pretty small, because of the narrow width of the hulls, I even can calculate it, but how to expand the metal???? Thanks for any advice, Christian

Hi Christian: You've asked a very difficult question. Any metal boatbuilder familiar with fabricating round hulls will know how to form your plates. With aluminum this is typically done with a hydraulic press, and simple wooden dies, rather than rollers (although rollers are sometimes used for some parts). This is very much an art and not a science--and if the builder with whom you are talking does not know how to do this, I would find one who does. Otherwise, you will have all sorts of arguments about what fits and what doesn't and whose fault it is! Regards--Steve Dashew

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Dears Sirs, I have read your book Offshore Cruising Encyclopedia with great pleasure and have decided to go on with building a new alu boat, about 45 feet. From a local designer I have got a design plan, including the areas of the hull, deck, cockpit and cabintop (the complete outer skin). The builder I have contacted is calculating the building costs for the aluminium parts by kg. The weight of skin of the hull, deck, cockpit and cabintop should be 1800 kg, excluding the inside frameworks and tanks. Do you have a good guess about how much the complete aluminium-part of the boat will weigh? The builder claims it you be factor 1.5 = 2700 kg. Regards, Jan B. Hansen, Sailmaker

Hi Jan: I have always done a complete weight analysis, calculating the weights of every piece of hull structure as well as all the other fittings. If you don't do the weight calcs in a thorough, detailed manner, both the weight and the vertical/longitudinal centers of gravity will be wrong. There are simply too many types of weight to guess accurately. Your designer will have worked up a framing plan, and it is not that difficult to calculate the quantity of longitudinals, frames, floors, and miscellaneous brackets. Good Luck--Steve Dashew

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Steve, Seeking your wisdom and guidance. I am looking at a 42' boat built in Holland made out of steel or aluminum. I live on Long Island and keep the boat in a marina. What is your suggestion for longevity and ease of maintenance, steel or aluminum? I am not so concerned about the price differences, but want the boat to stay healthy and metal hulls are basically an unknown to me. Thanks kindly, James

Hi James:

My personal preference is aluminum, especially in the size range you are discussing. Alum. is lighter, easier on maintenance (especially if you leave it bare), will have a lower center of gravity, and of course, perform better under sail and power. Where steel has an advantage is in impact resistance--however, assuming you are designing to the same scantlings, there will be little difference in most situations. The one issue which scares people is the threat of electrolysis. This is a bigger issue with alum. than steel. However, we've been doing alum. boats for 20 years now and have yet to see a major problem--as long as the boats are correctly wired--and care is taken with shore power (i.e. an isolation transformer is used). You will find a much more detailed discussion of the pros and cons in our Offshore Cruising Encyclopedia. Regards -Steve Dashew

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I am looking for designs for a steel yacht capable of worldwide cruising and being handled by a couple. Your ideas on yacht design seem to be the same as mine, particularly those regarding the priorities of equipment, safety, layout, engine rooms and cutting down on the fancy junk.

I am a naval architect and master mariner and am stuck in China for the next four years building a series of cargo ships and tankers. I would like to occupy my spare time by building a yacht for what I hope will be my imminent retirement after 35 years of building ships. Thus the requirement for a steel design.

In China there is high quality and cheap steel available but limited skills in welding, I also have all the cutting and bending equipment available to me. I am thinking of a design of 75 to 80 feet overall, this is I think the limit that can be handled by a small crew, my wife is not a great sailor in terms of usefulness on deck, otherwise brilliant but just ballast on deck. I liked what I can see of your Locura, I am conservative, I like Beowulf but the rig is new to me. I was thinking of a staysail schooner? I would much appreciate your advice, ideas, design suggestions or even a suggestion for a complete design to fit my requirements. Many thanks and best regards, Paul

Hi Paul: Sounds like you have the bug to build yourself a boat! Steel might be a good material for China, if the skills don't exist for aluminum. Our type of boats might not quite be what you're after, however, as the increased weight of steel would be an issue, especially with the vertical center of gravity. However, there are lots of good designers out there, and if you make a clear set of design specs--and feel free to borrow from our Offshore Cruising Encyclopedia for ideas--a competent NA should get you pretty close to where you want to go. Good Luck, Steve Dashew

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Hi Steve, Firstly thanks for the books, most of which are bending my shelves. I am looking for my first bluewater cruiser (second hand) and am paralyzed by the conflicting hull material shortcoming. You extol aluminum but here in Australia they are expensive and few and far between ( I would love one however). Steel ru