Marinair Ltd. : multiproducts

February 5, 2008

by Dick Trust, The Patriot Ledger (newspaper), MA, USA


The Patriot Ledger | Quincy, MA

Hitting a Foam Run:  Plymouth man says he has a better way  to keep damaged boats afloat

By Dick Trust                 For The Patriot Ledger Posted Feb 05, 2008 @ 09:2 AM 

PLYMOUTHHarry Shamir believes he has devised the most effective material to keep a capsized or damaged boat from sinking.The mechanical engineer from Plymouth last month incorporated his fledgling company, Marinair Ltd., which designs and distributes a new material called Floatfoam that keeps boats afloat when threatened with going under.“From dinghy or inflatable to multimillion-dollar yacht, you want it afloat somehow even if the hull is breached,” Shamir said. “This is a problem with older boats and boats longer than 20 feet that do not have air cavities filled with foam to prevent swamping if a hull breaks. One solution might be to buy a new boat, which is somewhat expensive.”Fortifying a vessel with Floatfoam, available as solid closed cell foam blocks, costs a fraction of a new boat’s price.Shamir says that one Floatfoam piece that is 24 inches by 25 inches by 2 inches, for example, has a suggested retail price of $89. He sells the material through his Web site,, and he eventually hopes to distribute through boat dealers, as well.The foam is attached to a boat by bonding with epoxy or by just a snug fit.He said it can also be used for light aircraft and hot-air balloon gondolas to increase chances of survival when crash-landing, and for automobiles to reduce personal injury and property damage in a collision.If a boat capsizes, Shamir said, “The only thing you can do is swim. But if the cracked or broken boat stays afloat, you’ve got something to hang onto. That’s the best life preserver.”Shamir said he saw flaws in the polyurethane and polystyrene materials that boat manufacturers have typically used to enable flotation.“One thing I know is that once you crash into a cavity of a boat that has polyurethane in it, the polyurethane breaks apart,” said Shamir, who also owns and teaches at the South Shore SaEF Fencing Clubs. “It’s very brittle and water may penetrate in quantities sufficient to risk the boat.”Polystyrene, meanwhile, has the potential to dissolve in gasoline, he said.“Floatfoam will absorb oil and gasoline,” said Shamir, who is 69. “That means you can actually clean out the bilge from oil and gasoline with Floatfoam scrap.”Shamir said he has made no sales yet, but Marinair Ltd. was only incorporated on Jan. 7 after years of development. Recently he has called on several boat builders who, he said, expressed some interest in installing Floatfoam at their plants to improve the flotation of the boats they are making.“I’m sole owner,” said Shamir, “(and) used my own personal money, even though I felt a recession nearing. I decided that, hey, it’s now or never. I’m not going to be as young as I am right now.”More information about Floatfoam can be found at the company’s Web site,

Photo taken by Jeff Loughlin, The Patriot Ledger staff photographer


January 15, 2008   


© by Harry A. Shamir 

In addition to the following marine application, FloatFoam can be used also for home construction purposes:  insulation both thermal and for sound, a material into which anchor bolts can be inserted easily and support lightweight items, lightweight walls, and more.   Assembly to wood and masonry by adhesives.

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Whatever size boat you own, from dinghy or inflatable to multimillion dollar yacht, you undoubtedly wish to ensure that whatever happens it will remain afloat somehow even if the hull is breached.   This is a problem with older boats and boats longer than 20 ft, that do not have air cavities filled with foam to prevent swamping if hull is breached.  One solution might be to buy a new boat, but that tends to be expensive.  Here are suggested ways to upgrade the existing craft. 

Joys of sailing and boating are always best when respect for water and craft are second nature.  This pablum statement needs elaboration:  always expect the worst, be prepared, and you'll probably survive most crises.  This article is about the boat being prepared by being made unsinkable, by using materials doubling as in-water survival gear. 

For quite some time the US Coast Guard has been promoting its Boatbuilders' Handbook, to be found at .  In addition to citations of the Law, it is also a practical guide to boaters and builders.  Here we are concerned with the Floatation chapter. 

The Floatation chapter goes into detail about the materials to be used for floatation purposes, where they are to be located, how to calculate the quantity, and what to expect as a result.  This article expands on some of these items. 

Usage of the two-liquids polyurethane self-expanding foam is quite commonplace and gives excellent floatation results.  It is a single use material, and not easy to work with:  any foam stains on clothes dooms the apparel since the material is an excellent adhesive and the fabric cannot be cleansed.  Moreover one finds after curing that the average density of the material usually given as 2 lb/cuft (32 kg/cumeter) is not uniform within the closed cavity in which it is poured or injected and expands.  The reason is that material coming in later in the pouring/injection cycle meets with resistance from the previous and now partially expanded foam.  Hence the later material will be denser whereas the earlier material will be less dense.  When pouring into a well defined cavity, the farside of the cavity must have a bleed hole for the air to escape.  However, some foam will also escape, requiring a cleanup operation usually involving scraping.  Expect some foam to escape also from the ingress hole.  It is very important to pour the correct amounts of the monomer and accelerant/foaming agent, at the recommended ambient temperatures.  Errors are very difficult to correct.  Also expect some air cavities within the foamed mass, that one cannot see unless slicing open a test volume.  The resultant foam is not always impervious to water absorbtion, and tends to be rather brittle to impact forces such as from collisions.  When used to enable floatation of older motor craft, very often there will be water and fuel and oils and other liquids being pushed out from the bleed hole of the cavity, by the expanding foam.  However, some will inevitably be left.  It is important to pre-extract as much of these liquids as possible before foaming the cavity.

Usage of pre-expanded polystyrene blocks is also commonplace.  This material is white, has consistent densities purchasable in 1.5 lb/cuft (24 kg/cum), and 2 lb/cuft (32 kg.cum), but is quite brittle and will disintegrate with very little force (the denser versions are better).  A good test for material quality is to use a spade drill 3/8" – 1/2" (9 to 13 mm dia) operated at relatively low speeds using a handheld electric drill, and seeing if the beads fall out easily or not.  It was originally designed for protection within packages, but denser versions are found performing other functions.  Nevertheless it is classified as rather weak.  The simpler versions of this material are quite inexpensive and can be inserted as blocks into nooks and crannies of the boat.  Since it is somewhat weak,  neither bolting it down nor adhesion bonding seem to work over time if the material is not mechanically shielded.   

Note that in contact with gasoline, the polystyrene dissolves within seconds.  This is actually a test for the material:  take a glass cup or jar, fill it with 1/2 of gasoline, drop the unknown material in, if inside of seconds it dissolves completely, the material is polystyrene. 

A significant improvement over polystyrene is a new material by Marinair Ltd, called Floatfoam™-A (  This is a copolymer that does contain a percentage of polystyrene, but most of it is another polymer altogether.  As a raw material is is by far superior to polystyrene, as it is much stronger, much tougher, and will not disintegrate when being worked.  This material can be bolted in place and will withstand the normal on-board wear and beatings without falling apart.  If damaged it can be easily repaired with most adhesives including marine epoxies.  Blocks of it can be easily cut to any shape with a cold knife, a hot knife, a hot cookie cutter, and other ways.  Use of hacksaws is not recommended since the resultant surfaces are not smooth.  It is quite easy to work with, and a round or oval section cut out from a block can usually be reinserted into the hole, yet remain extractable by a mild hand force.  If the re-extraction is too easy, by immersing the plug in very hot water the surface of the plug will expand somewhat and the plug will now remain in place.   This material is easily painted, especially by paints designed for polystyrene bouys.  In using it, it is recommended that the US Coast Guard instructions for polystyrene materials be followed (see Boatbuilders' Handbook).   For floatation uses internal to the boat, the 1.5 lb/cuft (24 kg/cum) is recommended since it is less dense than the nominal density of polyurethane, hence less precious craft volume will be used for floation needs.  For external bumpers use the denser versions are better, but invariably will need to be encased to protect from surface abrasions and the like.  This material is more expensive than polystyrene.  Quality tests are the same as for polystyrene. 

Floatfoam blocks are multiple purpose materials.  They can protect a boat from sinking by providing floatation if hull loses integrity, can protect hull and bulkheads against shocks and bumps from inside the boat, will mute noise and vibration, will insulate against heat loss, serve as seats when cushioned, or made into floating furniture including mattresses, all the while serving as inexpensive and efficient emergency life-preservers if so designed.  They can be tied together to form rafts.  A system of 9 blocks 2 ft x 2 ft x 4" (0.3 m x .3 m x 10 cm) can support up to 755 lbs (340 kg) if evenly distributed.  It is recommended that they be painted safety orange for easy visibility. 

Note:  Floatfoam-A will absorb gasoline without itself losing its geometrical size.  This means it can be used to soak up spilled gasolene.  By pressing upon the foam, most of the liquid can be recovered.  The material cannot be reused for floatation purposes after having absorbed gasoline, even if all the liquid was squeezed out of it. 

Enjoy your boating experience calmly, with security and safety.