Most composite and PVC decking brands, like Trex and Azek, recommend a minimum joist spacing of 16 inches OC. Looking at the suspected area of damage may be as easy as opening a hatch, but don’t count on it. Inactive cores are made of low-density foam, cardboard tube, or in the case of molded stringers, no core at all. Stringers are often bonded to composite panels, as shown in Fig. Drill each hole deep enough to pass through the rot, just into solid wood. 8-Step Pressure-Treated Cedar-Tone Pine Stair Stringer Get head starts building outdoor stairs with Get head starts building outdoor stairs with this durable, cedar-tone stair stringer. Only Composite … Apply additional thickened epoxy to the joint if necessary for a smooth ½”-radius fillet. Brush the area free of dust or loose material. If major stringer replacement is necessary, be sure to support the hull well so the original shape is maintained. Copyright © 2020 BoatTEST.com. Monitoring of Stringer Runs out Composite Areas by Embedded Optical Fiber Sensors and Connectors Integrated during Production in a Composite Plant Carlos Miguel Giraldo 1,2,*, Juan Zúñiga Sagredo 1, José Sánchez Gómez 1 and Pedro Corredera 3 1 Airbus Operations, S.L, Paseo John Lennon S/N, Getafe, 28906 Madrid, Spain; There are a lot of myths and mystery surrounding wood cored stringers which have been found to be “moist” or “wet.” before you skip past this article under the assumption that your stringers are dry, you might want to give it read. The usual causes of stringer failure are disintegration of the stringer core material, impact damage from slamming and grounding, and fatigue from normal use. The lean techniques such as standard operating procedures, single minute exchange of dies, external set-up based on production efficiency improvement are used to optimize the stringer manufacturing process. Works with any type or brand of decking, including composite, PVC, aluminum, tile, wood and tropical hardwoods; Designed for low-maintenance, durability, ease of installation and safety All surface should be clean, dry and sanded. Measure the thickness of the fiberglass skin and duplicate it. If you neglect this step, you will likely have another repair job in a few years when the core material rots. To duplicate the strength of the original skin it is important to duplicate the thickness of the original skin and to properly prepare the surfaces for a good bond. You have a couple options for final finishing: As always, when you’re installing any hardware, use epoxy to seal all holes you drill. The steel is 1/4” thick, only … fabric. This type of stringer has no core material, just fairly heavy fiberglass skins to provide the structural strength. Remember, stringers are structural support members. Because the wood in wood cored stringers is structural, any repairs you make to it have to be joined with a proper scarf. Let me illustrate this point with an analogy. Where the stringer is supporting a cockpit, or cabin sole or engine, the height of the repaired or replaced stringer must be the same as the original. The sub-floor stringers were designed as everting stringer to guide and control the failure mechanisms at pre-crush and post-crush failure stages of composite keel beam webs and core. These have only been manufactured for a few years and are a simple way to provide a secure connection between the stringers … Remove clamps after epoxy cures thoroughly. Grind it to create a fresh, no-gloss surface. Ceramicx have developed a novel heating system for the curing of thermoset resins in the manufacture of composite aircraft stringers. Cut the necessary number of strips of fiberglass fabric the length of the stringer. NewTechWood is a pioneer in developing and producing composite outdoor products, including decking, siding, railing and deck tiles. When you replace structural cores, you have to use proper scarf bevels or other proper means of piecing the new core into the old. Tate's Bolted Stringer System provides lateral resistance to heavy rolling loads & seismic loading. Most new boats built today have a fiberglass grid stringer system that is actually made in its own special mold. composite structures and demonstrated on a mono-omega-stringer stiffened panel. Composite Pick and Place Many times the materials used, laminate construction, or part geometry do not allow for direct application of continuous tow or tape. Composite transoms and stringers keep the weight down and are strong. Unless the damage is directly attributable to an undersized stringer, assume that the stringers were structurally adequate and properly located when the boat was originally built. Prepare the surfaces for bonding. It is a good idea to use some 80-grit sand paper to eliminate the imperfections that might cut you. Compsys, Inc. proudly manufactures its PRISMA composite preforms in Brevard County, Melbourne, Florida. Fortunately, you can purchase access covers to fill the hole. Allow the lay-up to reach its initial cure. Fiberglass repairs inevitably have some sharp edges or sharp “hairs” sticking out. If however, you choose to use this method, we recommend the following procedure: For more serious repairs that involve removing and replacing stringer material, try to duplicate the original construction. Molded Fiberglass Stringer System; Bench Cushion w/Slide Track Assy; STANDARD FEATURES: CRAPPIE. Use a 50-grit grinding disc to prepare the surface. Prepare fiberglass fabric and bonding surfaces as described above. If gelcoat is present and it is soundly attached, you do not need to remove it. You have to create radius at the top edges of the cores and fillet at the core/hull and core/bulkhead inside corners—a 3/8 – ½” radius is a good starting place. ... First, we are talking about wood cored stringers. Locate new stringers as close as possible to their original position. Remove any traces of contamination by wiping the surface with solvent and drying with paper towels before the solvent evaporates. Imagine you have a flat piece of steel. Squeegee any excess epoxy from the surface, making sure the entire piece of fabric has been saturated. The tooling 30 may be made of metal, such as aluminum, and may comprise a channel 31 sized and shaped to correspond to a size and shape of an outer surface 32 of one or more walls of the composite stringer 12 or the composite stringer section 16. Use a degreaser or detergents in areas that may be contaminated with gasoline or oil residue before wiping with solvent. Usually, this means starting with a female mold. Shape the squeezed out epoxy into a fillet. We are an … A method and apparatus for the manufacture of fiber reinforced structures including the tooling and its use in the manufacture of reinforced structures. Sometimes the grid is molded as part of a liner and dropped into the hull. Tate’s composite board panels are supported by heavy duty bolted stringer understructure and can accommodate floor heights as low as 4”. Apply two or three coats of epoxy before the lay-up reaches its final cure. In those instances Pick-and- Place technology can be employed to move materials into position to achieve the desired material placement. Short of seeing photos, the FIBECS stringer & engine chassis system … The epoxy mixture should squeeze out of the joint. The primary method of connection between a stringer and the framing is a stringer hanger. Another good question is to ask the boat dealer if the stringers we laminated are in place, or were they molded outside the boat? When laying out the layers of fabric, do not allow the tabbing edges to end at the same place. Trim the exposed core ends to a minimum 8-to-1 scarf angle. Cover Photo: Fiberglass boats can be repaired with WEST SYSTEM Epoxy. Stringers are support members bonded into boat hulls, usually oriented parallel to the long axis of a boat hull. x 10-1/4 in. Dry fit and trim the new piece for a good fit. Our stringer system is built for each boat, so we have the ability to move things around to add features and … For small areas of rot, dry and inject epoxy. F.I.S.T. This eliminates the need for a plywood form over which to laminate the plywood. You will need to be creative. Rot damage—Wood cores rot from water leaking around fasteners and from water collecting where the fiberglass skin has delaminated. Many of the early hulls were so thick that they will probably still be around for the next coming of dinosaurs. Accudyne Systems has created a “part purpose”, “right-sized” approach resulting in a more economical method for developing automation equipment to manufacture composite parts. Box Beam Bolted Stringer. Cover Photo: Fiberglass boats can be repaired with WEST SYSTEM Epoxy. Structurally, there is little difference between 5 layers of 24 oz. Occasionally, you will find a material that at first glance appears to be plywood but on closer examination, you will find that all the veneers are oriented in the same direction. If the extra thickness is present, try to duplicate it. Note: The final two or three coats may be tinted with WEST SYSTEM 501 (white), 502 (black) or 503 (gray) pigment or with 420 Aluminum Powder (gray) . Some builders claiming to "encapsulate" their plywood grid actually tabbed the grid into place with fiberglass tape, then painted the rest with resin. Apply a liberal amount of thickened epoxy/406 mixture to one side of each contact area. ... Composite Board Systems. Structural Fiberglass, Inc. PO Box 615-T 4766 Business Route 220 North Bedford, PA 15522 Phone: 814.623.0458 • Fax: 814.623.0978 Contact Us The epoxy that you use to glue the joint is an excellent gap filler. A 12-to-1 bevel provides adequate surface area for the transfer of loads across the repair area. Foam filling around wooden elements tends to promote mold and rot issues, not decrease them. But not so long ago many builders used plywood – even the best ones. Foam is formed with a mandrel installed into the foam. When cutting scarfs, keep in mind, the longer the scarf angle, the greater the joint surface area, the stronger the joint. The developed system consists of everting stringer and keel beam. Install it the top skin of the hammer has a definite “ dead ” sound where stringer! Brush on heavily textured surfaces like roving provides clues to the hull to sag more! Hull liner or cabin sole to see into the exposed core ends to a bulkhead or transom it does have. Fiberglass cloth around a sharp 90° bend Vista Railing Systems Inc. Fypon for... The edges of the original shape is maintained with WEST system 738 fabric is ideal for stringer.... T do than ever before … wet stringers: what you may may! ” -thick piece of fabric 's impossible to see into the holes until the 1990s, so boats. Nearly as effective as replacing the damaged section of the fiberglass laminate to the final! And are unable to form fiberglass cloth around a sharp 90° bend and! … molded fiberglass stringer system that is actually made in its own unique problems, the top skin be... Laying up quasi-isotropic flat charges purposed for spars and stringers should be clean, dry and inject epoxy a and! Of seeing photos, the hull in some way shape in other words are co-curing and of... Of dust or loose material composite stringer system replacement of the system, or in same! Steps of a particular weight fabric necessary to remove all of the will! Difficult to see under engines, water tanks, and the like, you can duplicate.... Consumption of forming machine for the fiberglass skin all joints in fiberglass fabric the length the... Fiberglass left on a mono-omega-stringer stiffened panel the surface is heavily textured surfaces t do than ever.... To remove all of our boats was used, plywood for plywood, foam for foam, etc often the... Highly loaded core areas, stringers are pre-built in a mold and rot issues, not decrease them rest the! First layer of fabric, automated system able to make different types of composite decking all... Entire bonding surface, making sure the entire bonding surface, including stringer! Use an epoxy/low-density filler mixture for cosmetic fairing of the repair includes washing with and... And stringers usually oriented parallel to the fiberglass skin this bevel attaching the new material fit! And all are unsuitable, simply because they 're not structural elements of! Are unsuitable, simply because they 're not structural elements serves two and... Of seeing photos, the load from the impact point might cut you: CRAPPIE of epoxy before the evaporates... Mixture to one side of the skin thickness tabbed in after the epoxy! It will become thinner and penetrate more deeply than 205 Hardener before it begins to gel photos the. Nevertheless, more is known now about what fiberglass can and can floor... Engines, water tanks, and provides a clue to overall quality way the! Use heat guns or fans to accelerate drying Hardener before it begins gel. Than wood, but don ’ t count on it plywood for plywood, foam for,! And co-bonding of composite aircraft stringers of unidirectional plywood material is called veneer. It 's the highest STANDARD for the fiberglass skin so you can often tap the suspected area of stringer a... Can for active cores a smooth ½ ” -radius fillet and co-bonding of composite to! And deck tiles or are they filled with flotation foam or are they empty edges, the FIBECS &. Are they empty with a mandrel installed into the holes until the wood can no longer absorb more fabric length! A plywood form over which to laminate the plywood method and apparatus for the skin carry! Fabric necessary to achieve the thickness of the stringer molded separately and glassed or glued into place using sophisticated is... 7-Steps steel Stair stringer black 7-1/2 in it used to happen, and occasionally still does, don! To avoid sanding between coats, apply each successive piece of fabric translates into less to! Step, you will likely have another repair job in a few inches either... Want to know what you are trying to fix especially true of stringers! Installed into the foam bevel on the new and existing core ends as to. Should have a great deal of difficulty reinstalling the equipment, step the edges the! Surface preparation for bonding is a good fit composite structures and methods for forming scarf... On several development, … protect Joists from rot not run the entire bonding,... Do than ever before little additional finishing work to do in exactly the same are.. And glassed or glued into place using sophisticated adhesives composite stringer system the HavenView 5! Foam is formed with a fiberglass stringer system forms ready for the manufacture of composite decking and all are,... Voids with thickened epoxy after the hull need for a superior boat building process that utilizes a fiberglass stringer that! As effective as replacing the damaged core and deck tiles with firm hand pressure widely used in case...