Scout’s built a reputation for being … Boats, as you may already be aware, spend a great deal of time in a fairly wet environment. The forms were made out of whatever was handy. Up to this point in the book, MEKP has been listed as the only hardener for use with polyester and vinylester resins, and proprietary hardeners listed as the only option for epoxy resins. That gap is called "shearing". When the panel has been glassed back in place, follow the manufacturers instructions for mixing and pouring the new core. It does not suffer from fatigue as does polymer panels, nor loose strength with age. One sheet of 4'x8' door skin only costs a few dollars from a lumber yard and will last you a lifetime of template making. To protect you from the elements without catching on fire. While it is true that plastic is more water resistant than bare wood, treated wood encased in fiberglass will resist decay almost as well as plastic. The problem with plywood is that it's susceptible to rot. Heavy Duty to Secure your rooftop tent, marine ropes, boating anchor, or bull float. Side note: Again, this is a product with which I am familiar. In the beginning, cores were almost entirely organic material. If a transom was a person, it would be a leather-wearing masochist hanging out at some inner city, middle of the night, club with blacked out windows and a nondescript door that requires a password to enter. BREAKING STRENGTH: 23700 LBS, COLOR: Yellow. The edges of the fiberglass would no longer line up with each other. What's more, it's compatibility with resin and its imperviousness to rot make it the only true. Trying to avoid the removal of a fiberglass skin will result in poorly bonded sandwich construction. Sounds simple right? It's lightweight, cuts easily, it's is highly resistant to rot, and it's chemically compatible with the resins used with fiberglass. 80 grit sandpaper on and orbital sander will provide adequate tooth for the new material. Don't worry, I'm not going to spend an inordinate amount of time on this subject because A) it's not particularly good reading and more importantly, B) I don't have a firm grasp of the science behind hydrodynamics. This is basically how fiberglass stringers work. How about for transoms? In Fiberglassic repair, we're dealing with the technology and knowledge that existed fifty or sixty years ago. You may only weigh 175 lbs, but on the downward motion, the needle might register 300 lbs. The problem is, without removing either the inner or outer skin, the inside surfaces cannot be adequately prepared for the new core. This content is copyrighted, and cannot be reproduced in any form without written permission from the author. A standard exterior grade plywood from a hardware store will have multiple voids throughout all the inner plies of the wood. Coosa Board is a suitable replacement for any wood core on a boat, from transoms to stringers, to bulkheads to floors. Let's do a hypothetical experiment. c. Carefully use a chainsaw to cut slots through the holes. It's made with a waterproof structural adhesive to bond the plies together. Wood has a tremendous advantage over plastic materials: Wood will not form stress fractures. Some companies use plastic materials as the load-bearing material in replacement transoms, reasoning that the plastic will not rot. Gatorbak - Boat trailer and watercraft lift synthetic bunk covers. Side note: Door skin is preferable to cardboard because it holds its shape better. If you are going to use a pourable transom core, the next step is to glass the removed panel back in place. It prevents the two panels of fiberglass in a transom from bending by limiting their ability to shear away from each other. Back to the balsa core. The small hexagonal voids also become individual pockets in the structure. That doesn't sound like the same thing at all. Torres Sport Fishing boats in Florida (among many others) are made almost entirely out of urethane cored laminate. Driven by innovation and committed to our customers. All of the previous holes, in both the inner and outer skins, should be ground back and re-glassed following the method described in Part One. The inner skin is often masked by splash wells or other components of the cockpit interior and may involve separating the hull from the deck. Ideal material for replacement of worn-out teak or plastic laminates. Strongest and Stiffest Composite Panel with the Absolute Highest Strength-to-Weight Ratio; Consists of Polyurethane foam filled throughout with layers of continuous strand glass and woven fiberglass; Over 30% lighter than Plywood with equal superior structural integrity! So how does this translate to a transom with a core? Combining different core materials can optimize the strength of the transom and minimize the weight of the structure, but, like every other concept in this book, it too has pitfalls. By the late 50s this mistake was largely rectified by reversing those roles. 5 Gallon Seacast™ Transom / Stringer kit : $222.95 - $242.95 : 5-K1 Buy Now 2 Gallon Seacast™ Transom / Stringer kit : $149.95 : 2-K Buy Now 1 Gallon Seacast™ Transom / Stringer kit : $99.95 : 1-K Buy Now 5 Gallon Seacast™ Self-Leveling Kit for Decks / Floors : $222.95 - … The alternative involves the use of a pourable material to cast a new transom core in place. OK. Now we're getting into a substance with some redeeming qualities. There may be alternatives under different brand names, but I am not aware of them. End grain balsa is a widely used core material for three reasons. Coosa Composites manufactures structural panels made of high-density, polyurethane foam reinforced with layers of fiberglass. Another factor at play with these materials is the layering necessary for excessively thick panels. A solid alternative to Urethane foam is Coosa Board. I cringe when I see or hear these words because I already know that the seller either has no idea of what's involved or is actively trying to dupe would-be buyers. Grind back the fiberglass on the exterior side of the panel using the 10:1 ratio described in Part One on both the panel, and the adjoining structure until you have the proper Vee shape, and start laying up new glass until the surface is flush. Great Decking and Transom Alternative - Do It Once - Do It Right! Use a 1” to 1.5” diameter wood bit/ auger with an extension bit, drill holes through the wood/filler core material from the top of the transom down near to the bottom of the transom. The material is a polyester based liquid to which you add a catalyst and reinforcing fiberglass strands. At Invision Boatworks we work with Seacast™ in our boat repair and restoration work. The result is an I-beam that is stiffer in every direction than a solid piece of steel that weighs the same. To ignore or downplay issues with any or all of these components is to willfully tempt fate. Pressure treating adds quite a bit of moisture to wood, so we use kiln dried plywood. It's unrealistically expensive. At Invision Boatworks we work with Seacast™ in our boat repair and restoration work. A better bond will occur if you do it another way. If you pick up the steel from one end and held it level to the ground, the other end would sag considerably. Imagine you have a flat piece of steel. It has to transmit the full power of the engine to the rest of the hull, as well as carry the pounding of the hull back to the engine. The answer to the second half of the question is much more likely to be misunderstood. It's also spun, braided, and used to make two ropes and safety lines for boats because it's stretchy and it floats. TRC75PV VETUS plastic transom exhaust connection with check valve, 75 mm The exhaust hose can be fitted directly to this transom connection. Some are good at neither, but are cheap and easy to find. One thing to note about this role reversal though, is that boat builders, as recently as a few years ago, did not understand this principle and relied on the core for at least some of the structural duty of the stringer. The downside it that it is already rigid enough that you may have a hard time getting it to conform to the shape of the hull. Either way, if the potential buyers take the seller at his word, major structural problems will end up being improperly repaired or dismissed outright. If they're not, then the result could be buckling and deformation of the transom leading to delamination and, ultimately, transom failure. or are they PE/VE specific? Solid wood had very low compressive strength. Furthermore, balsa turns to mush when it gets wet. The no-rot and light-weight advantages of high density foam combined with the structural properties of fiberglass make Coosa panels an excellent replacement for wood and other traditional core materials. The answer to the first part of the question is easy and widely understood. Its rigidity makes it unsuitable for curved transoms. Transoms were mostly cored with plywood. Your boat started off as just a hull, a silhouette of a boat. Hydrodynamics, or how a boat moves through the water is a combination of hull shape and displacement. Once the panel has been removed, the old core needs to be removed completely. This does provide and extra layer of protection if the panel should be punctured, but it is labor intensive and, in the end, over-engineered and no better than using an alternative core material. Side note: Years ago, when I was working on a casino boat in the Florida Keys, the company owners hired an outside consulting firm to come to the boat and teach all the supervisors tricks for training new employees. The only reason it's included in this list of possible core materials is to explain why it shouldn't be on this list. About Us; Blow Out Specials; How To; Blog; Policies; Contact; Shop by Category. A wood cored transom is almost assured of wearing out long before the rest of the boat. SX-A boating equipment pdf manual download. The transom of a power boat is the strongest part of the vessel. The volume of resin would generate so much exothermic heat that it would almost certainly catch fire. The structural element of the stringers became fiberglass while the core became more of a shape. For this reason alone, it's not suitable as a core material for transoms. The other difference is the number of voids in the plywood. In the previous example, 1” of core material was sandwiched between two ¼” fiberglass skins, resulting in stiffness 37 times greater than just ½” of fiberglass alone. If you can align the holes to where future hardware will be, then you can save yourself the trouble of filling those holes later. For this reason, whether using plywood as a core material or not, great care should be taken to ensure that moisture stays on the outside of the stringer. There are two differences. Boat repair materials, Transom repair materials, Deck and bulkhead repair materials, Fiberglass reinforcements for marine repair supplies by Carbon-Core. Here are my problems with pourable transom cores: First, like prepping any fiberglass area for repair, the surface must be contaminant free. Mixing and matching core materials is a viable option if you have a working understanding of how those cores will interact and where they're best used. Typically, I use ¼” of thickness for every 10' of stringer length. Repeat this procedure for the opposing surface and complete the sandwich construction. Any residual bits are going to compromise the new transom because of poor bonding, thermal expansion variables, and incomplete surface contact of the new core. Now imagine you have a cardboard tube. Additionally, most classic fiberglass boats were build with plywood transoms. Standard transom B. You can easily crush it between your fingers. Before we discuss how to rebuild a transom, it's probably a good idea to understand how they were built the first time. Additionally, the rapid expansion of wood from moisture absorption can cause the stringer to delaminate from the hull. Hardwood timber is the most widely used sleeper material. Let's say you have two lengths of ½” thick fiberglass that are both exactly 10' long. Side note: The previous sentence ended with the words “mat and roving,” because additional thickness of the stringer is the goal. It's prohibitively expensive. Zodiac uses a synthetic material which is continually evolving. When I repair a transom, I try to keep the weight of everything as close to the original design as possible. Fiberglassic Guide to: Transoms, Floors, and Stringers, Published: Monday, 06 September 2010 00:00. What is the difference between marine grade plywood and the plywood you buy at Home Depot? Another side note: When building up stringer thicknesses, I use a crude formula. In this book, this will be the only mention of BPO as a catalyst. New marine plywood, coated on CoreLite Board is 27% lighter than plywood. When fiberglass is not bonded to the core, the result is a transom that is only as strong as the thickness of a single skin. Rig Rite 3003.282 Manufacturing 920 Marine 3.5"x 12" Horizontal Transducer Plate Even with its high price, I always recommend it. CarbonBond POURABLE TRANSOM COMPOUND is ceramic filled polyester exhibiting exceptional physical properties. Plywood will also work just fine as a core material. If the new core material is not an exact match for the transom, the gaps can be filled with fiberglass mash or kitty hair. In an I-beam, two thin lengths of steel that are stiff in a left to right direction, but flimsy in an up and down sense are connected by a third piece of steel that is stiff in an up and down direction, but flimsy in a right to left sense. Compromising even a single one of the three puts the safety of the vessel and the lives aboard in jeopardy. The material has a paraffin base and just like the surf boards that are waxed so that the surfers can stand on them in the water, our platforms become more tacky when they are wet. We drill holes into it, assault it with solvents and grease, submerge it in water, and when we're done, we ignore it. Because penetrating epoxy is thinner, it requires a long time to reach full cure, at least 24 hours between coats. The overall increase was limited to the strength of ½” fiberglass plus the strength of the core material itself. When you understand that it's the shape of the stringer and not whats inside of it that provides the rigidity, it makes problems much easier to solve. What's more, it's compatibility with resin and its imperviousness to rot make it the only true permanent solution to many of the problems associated with boats, both old and new. Let me illustrate this point with an analogy. Until then, I stick with what works. – Materials – For a load-bearing structure like the transom (holding a Yamaha T70), am I good with your standard 1.5oz CSM + 1708 glass, or should I mix in something heavier as well? Because plywood is made from alternating grain directions of lumber, it is orders of magnitude more stable than solid wood. They all have different properties and drawbacks, so they can't all be painted with the same brush. The high cost of repairing a transom, (or any other structural element of a boat), is largely attributable to labor. We can either strengthen it or replace it altogether. Structurally it would need to be strengthened and stiffened before ever seeing the water. CoreLite is the leading balsa and foam core materials manufacturer that is revolutionizing the world and the way people work with composites. Nylon and Polyester are 2 examples. The door skin can be scored with a razor and snapped like Formica then shaped with sandpaper or a utility knife. Eventually the fuse is going to light. Urethane foam is also expensive and not always easy to come by. Solid wood is not a suitable core material under any circumstances! Perfect for off-road and recovery jobs. Whether it's ply wood, honeycombed, or any other material, the goal is to be as exact as possible. It is perfectly compatible with resin and it is highly rot resistant. First let's look at the mechanical aspects of these cores. In fact, wood gets harder as it gets older. Replacing a transom with a much lighter core may improve the overall riding characteristics of the boat, but it may not also. Conventionally, the transom comprises a plywood sheet, one-half to one-and-one-half inches thick, sandwiched between outer and inner layers of the basic … – Core material – should I just go with plywood, or is it worth spending the extra $$ on a composite/synthetic core material? Confusing the two can be disastrous at sea. Your boat is not lost if the transom has lost its integrity. Transom Wood/filler Removal Illustration A. The reason we all remembered these items is because they were the first and the last items mentioned. It's the same plastic used to make extruded parts and cheap children's toys. This is where things get a little trickier. Vacuum out the sanding dust using a shop-vac with a brush attachment, and wipe down the surfaces with a clean rag and either acetone or denatured alcohol. 5 Gallon Seacast™ Transom / Stringer kit : $222.95 - $242.95 : 5-K1 Buy Now 2 Gallon Seacast™ Transom / Stringer kit : $149.95 : 2-K Buy Now 1 Gallon Seacast™ Transom / Stringer kit : $99.95 : 1-K Buy Now 5 Gallon Seacast™ Self-Leveling Kit for Decks / Floors : $222.95 - … Now that we've covered the options available to you for rebuilding the transom, it's time to actually do the job. A wooden core was laminated to the inside of the fiberglass transom skin and a new build up of fiberglass was then laminated onto the wooden core. Balsa is generally used as a core material in hulls and decks, but not usually as a transom core because, while it's compressive strength is decent for bedding hardware without deforming the laminate, asking it to withstand the pressures exerted by an outboard motor is over the line. Do Not Use Solid Wood As A Core Material! When the core is continuous throughout the transom, it isn't a major factor because it will expand and contract evenly. Dig out the old core leaving the fiberglass skins in place, then mix up the pourable core and fill the void. Replace your bunk carpet with Gatorbak today! Most people could remember between 6 and 10 of the items. The transom, floor, and stringers in a boat are, collectively, the most important elements of its construction. Well, a hexagonal support structure between two fiberglass skins makes for a rigid sandwich that is protected from shearing in three directions. With a range of 15 stunning colours and three different caulking lines, boat fitters can personalise decks with more than 45 unique options to suit any style. Then wet out the mating side of the core material and lay it in place. John Greviskis of Ship Shape TV discusses Coosa Composite Board as an ideal substrate material for your next boat improvement project. Light synthetic coats can catch fire easily if you’re hit by a flash-bang grenade or a protester’s firework. Cored fiberglass, or sandwich construction, as stated above, is stiffer than solid fiberglass of equal weight. The problem is that most boat manufacturers do not use treated plywood. The most important characteristic of a fiberglass stringer is its profile, its shape in other words. There are others as well, but this section should not be read as an endorsement of one over the other. The increase in strength was hardly even noticeable. It's their shape that provides the support, the core is simply there as a form. Posts: 93 Likes: 0 Received 0 Likes on 0 Posts will the "nida" products work with epoxy? Interestingly, every single one of us remembered two specific items. My experience is with the two that were mentioned so I'm going to speak from that perspective. In a perfect world, the core is perfectly bonded to the skins and the repair is a permanent solution. The steel is 1/4” thick, only an inch wide, and it's 15' long. strengthened in corners. When you lay them on top of each other, the outer edges line up perfectly. When people are given too much information at once, they can't digest it all so they remember what stands out to them. The alternative involves the use of a pourable material to cast a new transom core in place. Blades will dull down to the nub in a hurry when working with this product. Coosa Composites manufactures structural panels made of high-density, polyurethane foam reinforced with layers of fiberglass. Honeycomb cores are the next generation of core materials and, even though they are both costly and not always readily available, I think these are the first evolution of fiberglass construction that is, hands down, a distinct improvement over standard organic cores. As you can see, adding a core between two fiberglass skins is a great benefit to stiffness. Stringers, deck beams and other supportive elements are formed in one continuous mold and glassed into a bare hull as a “pan” with no core material whatsoever. Adding layers of mat and cloth wouldn't build up thickness as quick. PlasTEAK Products Synthetic Teak and Recycled Plastic ... custom made, one at a time. Under the constantly fluctuating forces experienced under load, a transom will flex and bend. View Swim Platforms. With the new core cut and sealed (if necessary), the next step is to apply a binder to the inside surface of the remaining transom skin. An ideal material for a wide range building projects to replace worn-out teak or plastic laminates. But the price has come down since its introduction to the market, so that gives me hope. A boat transom and method of constructing same utilizing the outer skin of the hull and transom while still in the hull mold. Its role in boat construction is to stiffen the hull. Grind it back on both sides of the cut line until you have a 10:1 taper creating a Vee groove, then, as described in Part One, lay up new layers of fiberglass until the groove is flush and the panel securely glassed to the rest of the boat. As the boat flexes underway and the motor vibrates against the transom, any voids in the core will quickly spread to wide areas of delamination. Like most things that promise too much, it can't always deliver. If I knew a naval architect who was willing to tell me what the optimum weight is for a specific transom, I'd be happy to work within those parameters. Some companies use plastic materials as the load-bearing material in replacement transoms, reasoning that the plastic will not rot. They are then glassed to the hull and “Presto!” you have a stringer! Using a core material that is highly susceptible to water damage on a boat is a little like storing fireworks in the cabinet above the stove. Urethane foam is probably the best substrate you can use. When done in this manner, a pourable transom is the best, strongest, and easiest for the at-home boat restorer. Location: Rockport, TX. Marine plywood will use an exterior grade glue that is UV resistant. back and edges, bonded to Because plywood alternates the grain direction between plies, it is inherently more stable than solid wood or end grain balsa. The 380 is an innovation masterpiece. If you must first use a penetrating epoxy to seal the plywood, you must use epoxy to bond it in place. If you can't get clamps in place, drilling holes and using through-bolts with extra large fender washers or battens on both sides will work. Coosa Board is basically micro thin layers of fiberglass laminate built up to be a specific thickness. Awlgrip HDT Topcoats; Abrasives. There are variables to this formula, such as the number of stringers and their profile (some profiles are stronger than others). A working understanding of the concept is vital ensuring a safe repair. A transom being installed Regular exterior grade plywood uses the same glue. View Bow Pulpits Bow ... commercial grade, maintenance-free recycled material and we offer Memorial Benches that can be personalized. In the early days of fiberglass construction (mid 50s and earlier), the stringer core material was given the structural duty, with a layer or two of fiberglass overlay simply to hold it in place. The no-rot and light-weight advantages of high density foam combined with the structural properties of fiberglass make Coosa panels an excellent replacement for wood and other traditional core materials. The concept is an easy sell to a Do-It-Yourselfer. This is essentially what a core does. A transom is often the thickest panel on a boat because it requires the greatest strength and rigidity. Additionally, it is hell on tools. The down side to plywood is that while it's less susceptible to rot than the previously mentioned options, it isn't “rot-proof”. A bulkhead is disposed in forwardly spaced relation to the outer skin of the transom and the space therebetween is filled with high tensile strength synthetic resin which may be of the polyester type blended with a suitable hardener. For most people, this is the beginning, the end, and something interesting in the middle. Drilling holes in the transom to mount an outboard motor is like dangling the fuse next to the pilot light. Solid wood is more rot-prone than any other material. Sterndrive & Transom Shield. Other materials included end grain balsa and solid wood. Solid wood is great for building wooden boats. When you hang a 250 lb outboard from your transom, any flexing will amplify the amount of force caused by motor. So was Airex. When you hang a 250 lb outboard from your transom, any flexing will, Naval architects take these complex equations into account when they design boats.