Fibreglass and Fibreglass TapingThe KINETIX® R246TX high performance laminating system is specified for laminating the fiberglass tapes in DuFLEX kit construction, and for additional reinforcements that and fiberglass reinforced panels may be required, such as curved areas of a kit that need to be strip-planked and fibreglassed on each side, or for extra reinforcing in specific areas. This system is specifically designed for room-temperature fiberglass lamination and provides extended working time and excellent mechanical properties in the cured laminate. KINETIX R246TX has a mix ratio of 4:1 by weight and ATL recommends the builder to purchase a small electronic scale to ensure accurate measuring. Temperature and humidity levels should also be considered before you begin the laminating job. * When the temperature is low, epoxy becomes thicker and flows less. This makes the epoxy harder to apply. It also increases the possibility of air bubbles becoming trapped in the mixture, which reduces bond strength and moisture barrier effectiveness. * Epoxy will usually cure without clouding or other moisture-related symptoms with the relative humidity as high as 80%, assuming that there is no other source of moisture contamination. One problem with extremely high humidity is that there is too much moisture in the substrate to obtain a good bond. Unless the design has been specified to have the core rebated at panel joints, epoxy/fibreglass tapes are applied on the inside and outside of where the DuFLEX panels meet. Prior to taping, it is important to prep the surface well. Make sure the surfaces are free from contamination and have been sanded well to key the surface for good adhesion. Use WEST SYSTEM resin/hardener with 403 Microfibre Blend to create a neat cove in the join prior to applying your taping. Ideally the coving and taping should be done wet-on-wet to save work and time, and to give a nice, neat finish. A 20mm radius is generally sufficient. Take into consideration the number of layers of tape that need to be applied and stagger the joins to reduce bulky overlaps, and keep the tapes neat and straight. To optimise the strength of these tapes, the fibreglass or the fiberglass reinforced panels need to be oriented in the correct direction over the join. If in doubt, ask your designer or materials supplier.
Applying the tapes
2. Unroll your tape and position it carefully over the wet epoxy and cove, and in most cases the surface tension will hold it in place. If the area is too vertical, you may want to wait until the epoxy becomes tacky. Work out any wrinkles by lifting the edge of the tape and smoothing from the centre with your gloved hand or a squeegee. 3. Apply a second coat of epoxy with a foam roller to thoroughly wet-out the fabric. 4. Squeegee away any excess epoxy before the first batch begins to gel. Drag the squeegee over the fabric, using even-pressured, overlapping strokes. The object is to remove excess epoxy that could cause the fabric to float off the surface, while avoiding the creation of dry spots caused by squeegeeing too hard. 5. Finally, run a brush down the centre of the cove to make sure you have good adhesion. Repeat steps 2 thru 5 until you have applied the correct number of tapes to the joint. If tapes cannot be applied wet-on-wet, it is wise to apply a layer of peel-ply tape to the last layer to avoid having to prep and sand the surface prior to applying the next layer of tape the following day. ATL's Bonding Angles have been designed to provide a quick and effective means for making right angle joints between DuFLEX panels. Bonding Angles are fast and easy to install with a high density adhesive and are perfect for hard to access areas and overhead work where fibreglass taping can be difficult. ATL Composites has developed the Wombat Junior Fibreglass Taping Machine to reduce the time required to wet out tapes and to minimise the handling of liquid resins. Junior is easily operated and gives the laminator greater control of the resin-to-fibre ratio. Rolled up, wetted tapes are easily carried to the job and rolled into place.
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