the hull, the strength test

when I was very young there was a man who boarded with us- My dad and I were building a BARTENDER, from ply with massive chines, stem and stern members
Anyways this bloke said you "should be able to belt a hull with a 20lb sledge and it should be able to stay intact"
Years later I read of a boat sunk by orca, she was oaken planked 1 1/4 inch with close spaced oaken frames and floors, she sank in seconds, the book ,Survive The Savage Sea
later again I became a long time builder of metal yachts , oNce I stood on a plank and belted as hard as I could with that hammer a reluctant seam on a tight U forefoot, I was thrown off the plank, only gradually did I move the 5/16 , 8mm plate
I read abt the fleet of steel 65 footers going round ( the wrong way) and how every one of then tinn canned the forefoot area, either too lightly plated, soft plate of too wide frame spacing or all 3
To me having been at sea in tugs, and also sailed such stormy seas as the Tasman, it seems that the sledge hammer test is a good and sensible one
I saw a bloke launch a cat here, he told me he was going to Fiji, 3/8 ply, a mere flick of a sleeping mammal tail would sink that boat, but I just said to him, nice job
YET how many boats could take the hammer test?
When I,m surfing down a wave at night I like to think I,m safe
Greens perhaps the most successful of carbon fibre builders ever, where made to build a section of hull that would be used in such testing for the new boat Shamon, an iron weight was swung at the piece, I am not sure of the weight but it was pointy!!
Greens have had great success with carbon, their round world racers such as Innovation,kaverner surviving totally intact
what do you reckon, can your new boat comply?
And here I think I mean for offshore capable craft

 

Right up our alley

Whoosh,

The hammer test is our advertising tease. I say tease because no conventional manufacturer has stepped up to the plate yet.

I will let any pleasure craft manufacturer take a swing at my Fer-A-Lite hull with a sledge hammer, provided I get the same opportunity with one of theirs.

We manufacture Fer-A-Lite polyester brand mortar mix. It is used in a construction method similar to Ferro-cement, without the concrete. We like to think of it as Steel Reinforced Plastic, or a Steel Hull with a protective covering.

The material has a modulus of elasticity similar to aluminum. When reinforced with steel rod and Wire Plank or similar mesh material it will survive a beating with a 20 lb sledge. In fact if you are not careful the hammer will bounce back with full force.

Unlike portland cement, Fer-A-Lite does not allow any moisture migration to attack the metal armature. It is also 60% lighter than portland.

The material has a 99% secondary bond strength, which means you can repair it easily with assurance that it is as strong as the original.

There are hulls well past 30 years that are still out sailing, Reid Stowe is currently on day 642 of a planned 1000 days at sea non stop in a hull he and his family built over 30 years ago out of Fer-A-Lite, they decided to use the material on the entire boat after putting on a test patch and then beating on it repeatedly with sledge hammers and fire axes with no apparent effect.

In addition, a few days after setting out on the voyage they were hit by a Maersk lines freighter. It bent the steel bowsprit back over the boat, ripped the steel fittings just proud of the Fer-A-Lite hull, but no damage to the hull material itself.

Our 25 year old Fer-A-Lite ketch was put on a concrete seawall during hurricane Francis back in 2004. 8 hours of heavy seas, heavy winds caused a small hole to form in the bow. However she broke the sea wall in two places before the 6" opening appeared in the bow.

Time consuming construction, but it pays for itself down the road with minimal maintenance, no blisters and stronger than anything else out there.

www.fer-a-lite.com

Fer-A-Lite hulls are not afraid of things that go bump in the night.

 

darr....

Just off hand fer-a-lite appears a very expensive (from your price list) way to build a boat. Please give a materials price (hull & deck) for the Mobjack.

 

The mobjack listed in Platt's book on our website was built by him and his family. I do not have the materials list for it.

However in the PDF there is chart that will give approximate quantities of material needed per given size and usage of vessel.

The pricing on the website is still being reviewed and based on the order quantity has been proven to be much less than the advertised costs.

It is a more expensive method of construction, no doubt about it, but, on the other hand what price safety? durability? ease of long term maintenance? peace of mind? or as the great visual from a line in the original post to this thread

"When I,m surfing down a wave at night I like to think I,m safe"

It would be a pity I think to not have the absolute confidence in my boats ability to survive a given situation, all for the sake of a few dollars differential in the construction of the hull.

This material and construction lends itself better to a mid to heavy cruising design more so than a light racer, although I am trying to track down rumours of a multi hull that was built on the east coast with the material prior to our involvement.

Not to say this material is indestructable, nor that a Fer-A-Lite hull cannot be lost to the sea, as anything made by man, can be destroyed by man or lost through negligence of the captain or crew.