Aluminium vs Steel Mono for Living Aboard

[gouralnik]

Hello Everyone,

I was reading on this forum for over a year, have accumulated a lot of information (thank you), read many sailing books (regarding technical as well as adventure aspects of sailing) and wanted to open a new thread, because I want to gather your input on my particular situation. I'm welcoming any suggestions - please be open minded about it. I am not a seasoned sailor, but I have been on a few sailing trips and living on board for 5+ years sounds attractive to me and my partner - we are very spartanic in our attitude. We consider buying a monohull boat instead of a flat, live on board, work, save up money and cruise in free time - in and around Australia primarily. Later on maybe an extended voyage to more remote destinations in sub-tropical / tropical climates.
In my free time I am reading about boats and trying to figure out the "optimal", though I know that there is no such thing as "optimal".
Here are my parameters and I would like your input, knowledge and advice.

1. Aluminium vs. Steel --> this topic drives me insane; could not find any good ship yards specialising in steel (as for aluminium ovni, bestevaer design...).
2. Length: 43 - 57ft
3. We might get kids in 3+ years (2).
4. We both love no-nonsense designs where it's all about function and not style (I drive a Land Rover Defender and fix whatever I can myself - if that could somehow resemble my attitude) - so what's important is that how easy it is to run, maintain and fix if something goes wrong especially in less civilized countries.
5. Is it a good idea to obtain design plans first and then go looking for a builder?
6. Price range I will leave open as I do not want to limit your imagination

I would appreciate any comments from you on this issue. Thank you.

[Maren]

I'm not sure what the question is.

Are you asking about the advantages of one material over another or are you looking for a recomendation for a designer? Also, I'm not sure why you've fixated on a certain size considering your level of experience. I'm not saying it is or isn't what you might need, I'm just trying to figure out what else is unsaid.

Either way, it might help to get a bit more on clear on what you sailing goals are. If you are looking for a coastal cruiser, that's a different boat that ocean going boat. You get openness and comfort but sacrifice suitability at sea -- not a bad trade off for those who really don't intend to go to sea.

Also, budget is pretty much always an issue and you'll do well to consider it initially. Maintenance tends runs about 10% of boat value per year over the long term. Add to that taxes, add to that cost of cruising.

[noelex 77]

IMHO aluminium is a much superior boat building material to steel. Ther are lots of aluminium boats that not OVNI's (A good design if you want a lifting keel yacht, but I did not ) The major drawback is aluminium is that it is more expensive. If you want to build a new alumium yacht of about 45 feet an equip it for offshore sailing you are looking at about AUD $1 -1.5M even with a basic fit out (and I share your view that a basic/functional boat is best)
In steel the costs are less, but the maintenence is higher and the resale price much lower.
Having faced the same problem, I decided a second hand aluminum boat that had been designed for the original owner to travel around the world was the best option. In retrospect I couldnt be happier with my desision.
If you prefer a steel boat with the current economic problems these can be picked up second hand very cheaply, but be prepared for lots of mainanance.

[neelie]

Take a look at the Radford design kits; he designs for both materials. RADFORD YACHT DESIGN - Home page

If you have the skills, employ a welder to build the hull for you and then fit it out yourself as and when money is available. The main consumer of time and money is the fit out.

As to which is better?.. Maybe aluminium but not by much. Steel is good too if it is built properly from the start. We once owned a badly built steel boat - I swear I could hear it rusting as I slept. Second hand steel boats are always suspect unless you can guarantee it was built properly, and this is not an easy thing to do.

[Sharkman]

Both are great materials for long term living aboard, but as has already been mentioned by Noelex steel is cheaper, although if you want a really good paint finish the difference is often not so great.

Steel might also be easier to repair in any out of way place in the event of any major structural damage, but you would have to weigh up how likely you think that might be to happen. For both materials it's important to be able to get to the internal structure to keep a careful eye out for periodic inspection, especially with steel where rust can rapidly become an issue.

Aluminium has so much going for it - it's relatively easy to construct a fast cruising yacht that is immensely strong without the weight penalty of steel, and it lends itself to modification or one-off construction. We chose an aluminium boat for many of those reasons and having lived aboard for a while now have no major concerns. We are more careful where we leave the boat, and don't like to leave her unattended for long periods on marinas, but as we are generally on the move and living aboard that rarely happens. There are things that we are very glad we did at the build stage such as have the hull and deck insulated, which not only cuts down condensation and keeps the boat warm in higher latitudes, but also keeps her cooler inside when it's hot - and definitely cuts down noise down below, which can be a nuisance in some aluminium boats.

Metal boats are great, for all that they require a little more from their owners. There's another OVNI 435 behind us that has just come back from the Caribbean and the owner was telling me that they hit some sort of floating debris really hard when crossing the Atlantic that had left an 18" long scar down the hull plating, which would require some filling and fairing, but nothing worse - aluminium boats are tough.

But maintenance free? No - I've just spent the weekend touching up the external paint finish, and it's true that keeping it looking good takes time and effort, but this has been annual maintenance. It's not necessarily a big deal if you stay on top of it, and is another reason why metal boats suit liveaboards - if you're there to keep an eye on things you can stay ahead of the game and keep your boat in good shape.

And if you want to keep it simple, then don't plan on more boat than you need - in so many ways size = complexity + cost.

[barnakiel]

Originally Posted by gouralnik

Hello Everyone,

...

1. Aluminium vs. Steel --> this topic drives me insane; could not find any good ship yards specialising in steel (as for aluminium ovni, bestevaer design...

No kidding. Just check out who builds for Koopmans, Van de Stadt, etc.. I have never seen better built boats, in any material.

Alas. Some US build boats come in steel and they are jewels - perhaps the boatyards are still around ?

Send an e-mail to Kanter's ask whom they could recommend for steel. They will know.

b.

[bewitched]

Aluminium for me (if I could afford it)

I think you would be hard pressed to beat Van de Stadt for design.

[bitman]

@sharkman, thanks for this comprehensive report!

just spend a week on an ovni 385 and they are strong!!! one of the crew members dumped it against the pontoon with the fenders on the other side.... not even a scratch on the top sides.

but painting... i know aluminium boats totally unpainted as it's only for cosmetics. well you can but some (special) anti fouling on it to keep the bottom clean. or install a sonar system.

[galleyslave]

noelex 77's comment on resale is somewhat dependent on location. According to a broker I talked to recently, aluminium boats are pretty much unsaleable in SE Asia.

[stillbuilding]

Had both alloy and steel. I had more trouble with the S/S fitments on the alloy boat than with rust on the steel but builders have learned about electrolysis since then (80s boat). Sold the alloy boat cos I really did not want to remove the toe rail.
Hard to find good builder in either but they are around. A good builder could build in either. I was lucky enough to find a great German craftsman.

Paint on alloy is a right PITA - consider NOT painting. Interior had to be I guess but always flaking off and I was always having to watch for bits of copper wire etc dropped into the bilge. A copper swage on a jackline ate most of the way through the deck in matter of months.

Had electrolysis problems near the lead keel which entailed cutting out a decent patch of metal.

Overall, steel is economically better.

[sokkum]

Don't miss the proven designs from VAN DE STADT DESIGN - Yacht Designers, Naval Architects (Van de Stadt design that is) for study and building plans of sailing yachts in steel/aluminium/wood core.

[bitman]

Originally Posted by stillbuilding

Had both alloy and steel. I had more trouble with the S/S fitments on the alloy boat than with rust on the steel but builders have learned about electrolysis since then (80s boat). Sold the alloy boat cos I really did not want to remove the toe rail.
Hard to find good builder in either but they are around. A good builder could build in either. I was lucky enough to find a great German craftsman.

Paint on alloy is a right PITA - consider NOT painting. Interior had to be I guess but always flaking off and I was always having to watch for bits of copper wire etc dropped into the bilge. A copper swage on a jackline ate most of the way through the deck in matter of months.

Had electrolysis problems near the lead keel which entailed cutting out a decent patch of metal.

Overall, steel is economically better.

with those kind of problems all points out to be a bad designed and build boat. have seen some aluminium boats of some age with non of those problems.

those ovni's have special coat on the inside (bilge) of the boat so that a copper wire doesn't do any harm. also the ballast is being isolated from the hull... they build only aluminium boats since the 70s.

[Cheechako]

I just have trouble wanting anything steel around salt water. Having said that, steel is nearly 3 times as stiff as Aluminum. (modulus of elasticity) Aluminum welding can have it's issues also, some welds stress crack over time etc. Paint can be very difficult to keep on aluminum. (friends of mine had their 48 ft alum boat painted 3 times) So do it like the French... dont paint it! If you are unlucky and get a bad combination of componants on your dream boat, it could corrode through in one year due to electrolosis! There was a commercial boat up here in Seattle that did just that! All the above of course are worse case scenarios and there are a lot of very nice alum boats around. If you must have a particular boat... go for it!

[S/V Alchemy]

Originally Posted by stillbuilding

Had electrolysis problems near the lead keel which entailed cutting out a decent patch of metal.

Overall, steel is economically better.

I like both, but as you pointed out, aluminum/aluminium is "trickier" in some respects due to its position on the galvanic scale.

We chose steel (a late '80s custom pilothouse cutter) because of opportunity, because the then-20 year old boat had never seen salt water, because of the build quality, and because I believe I understand steel's pluses and minuses and am prepared to deal with issues both galvanic and corrosive.

Yes, I do paint touch-ups and no, they aren't onerous...in fact, I equate my weekly "circling of the deck" to the same sort of inspection done by small aircraft pilots who typically do a walk-around before each flight to look for dents, bulges or irregularities that shouldn't be there. Once I caught a cotter pin partially worked free of its clevis pin on a stay that I would not have otherwise seen were I not in the habit of looking for rust spots. This can't be a bad habit.

The boat is, by plastic standards, heavy, but not vastly so as it's not, in fact, overbuilt in steel. So I will never take line honours, but I can keep more canvas up longer than many intrinsically faster boats, and cruisers aren't always about point to point speed, anyway. I certainly have a great deal of reserve buoyancy and stowage space, and I carry greater tankage, giving us a stiffer ride. This is desirable for long-term, long-distance cruising in a way a coastal daysailer would find objectionable.

In a perfect world, I would have a sleek aluminum cruiser to sail to the coral reef surrounding the paradisical tropical lagoon, but I would have the steel boat once I got there. You know, if my navigation was off!

[GordMay]

Michael Kasten has numerous interesting & informative articles on metal boat design & construction:
➥ Articles by Michael Kasten - Kasten Marine Design, Inc.

On Metal Boats

Metal Boats for Blue Water - Why choose metal for a boat's structure?

Any discussion of metal boats inevitably encounters the question of whether a boat should be aluminum or steel. Not often realized is that there are other metals that may be effectively used. "Metal Boats for Blue Water" is intended to provide an overview of the possibilities, and to discuss why one might choose metal for a boat's structure.

Metal Boat Building Methods - When planning to build a metal boat, what's the best approach...?

Should you erect the frames first and then apply the plating, or vice versa, should you first pre-cut the plating, weld it all up, and then install the frames afterward....? Or are there yet other approaches...? These are the questions we've addressed here, primarily to define terms, and then to outline the alternatives and their relative benefits.

Steel Yachts - Some people claim that steel is too heavy for use as a yacht building material. Is there any truth in that claim...?

Given the weight of steel as a structural material, isn't it too heavy for small yachts...? What is a practical size limit...? In the mind of the public, there seems to be quite a bit of misleading information. What's the deal...? Check out a few thoughts on the possible advantages of steel.

Aluminum for Boats - Is there good reason to consider aluminum over other hull materials?

This article first appeared in the September 1997 issue of Cruising World magazine. It includes several good images showing different hull forms suited to metal construction, the relative advantages of each, and what factors one should have in mind when considering the use of aluminum as a hull construction material.

Aluminum vs. Steel - A comparison of their relative strengths, and the advantages of each...

The choice of hull materials is the most fundamental of choices when considering a new vessel design, or even when considering the purchase of an existing boat. If you intend to make use of metal as a hull material this article will be of some value in that choice. It will shed some light on the various ways to compare steel versus aluminum for a boat's structure.

Corrosion Prevention - A simple summary of the critical elements of what one can do to prevent corrosion in metal boats (or any boats that have metal below the water!).....

The strategies outlined here are aimed at the boat building process, at which time one has the very best opportunity to create a hassle free, low lifetime maintenance situation for any metal vessel. Vigilance and good workmanship are vital...!