Carbon Fiber Fabrication Kit Instruction Manual

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1 Carbon Fiber Fabrication Kit Instruction Manual Thank you for your purchase of an Eastbay Composites Carbon Fiber Fabrication Kit. This kit will provide you will all the components you need to make high quality parts out of carbon fiber using an existing mold. Please read these instructions thoroughly before you begin making your first part. Read the warning labels printed on all components before use, always use all components in a well-ventilated area, and always wear eye protection, a facemask, and the included gloves. The Carbon Fiber Fabrication Kit The following components are part of your mold making kit: 2 pairs Nitrile Gloves 4 Mixing Cups 4 Laminating Brushes 1 oz. Mold Release Wax 2 oz. PVA Mold Release Agent 12x oz. 2x2 Twill Carbon Fiber Fabric 12x36 Standard Weave Fiberglass Fabric 10 oz. Epoxy Resin 5 oz Epoxy Hardener What You Can Make With Your Carbon Fiber Fabrication Kit Your Eastbay Composites Carbon Fiber Fabrication kit is designed to allow you to make a single layer carbon fiber part up to approximately 10x34 or multiple smaller parts, depending on complexity and the number of carbon fiber layers you use. The directions and the kit are designed around making a carbon fiber part based on an existing mold you provide. If you don t already have a mold, you can easily

2 make one with the Eastbay Composites Mold Making Kit available on our website at A plastic switch plate will be created as an example for the following directions but you are free to make any appropriate part from a mold you already own or plan to make. While there is great flexibility as to the item you choose to make out of carbon fiber, please use the following guidelines for the best results. This list is intended as a guide only and we always encourage our customers to develop new ways to get the most out of our kits (please let us know how you did it!). Your part should have a good side and hidden side. These directions do not cover the process of making two sided molds. Avoid parts that are tubular or round. Parts that require hidden threaded fasters on the backside of the part add complexity to the model and are not included in these directions. Models that are fastened via adhesives or through holes in the final part are the least complicated parts to make and are recommended. Parts that have cut backs or indentations require soft molds or multipart molds and are not recommended. These parts will be more difficult or impossible to remove from your mold once it has cured.

3 The Mold Before you can make a carbon fiber part with this kit, you will need an existing mold. Since the carbon fiber cloth that came with this kit is 12x36, your mold should be somewhat smaller than that. If you don t have a mold you can make one with the Eastbay Composites Mold Making Kit available on our website. We will be demonstrating the use of this kit with a mold of an electrical switch plate that was made in the instructions for the Mold Making Kit. Applying the Mold Wax To ensure that your carbon fiber part releases from the mold easily and without damage, it is essential that you apply mold release agents to the surface of the mold. This is a two-step process to ensure easy separation. The first step is to apply the mold release was that came with your kit. With a soft cloth, apply a thin even layer of wax over the surface of the mold.

4 Be sure to apply the wax to any surface that might come in contact with the epoxy resin. Even the sides of the mold should be waxed to ensure that all the epoxy comes off easily. Also keep in mind that if the wax is applied too thick or in clumps, those imperfections will appear on the surface of your final part. Applying the PVA The second step is the application of the PVA mold release agent. Apply this liquid with a soft cloth to all the surfaces where you just applied the wax. The PVA essentially does the same thing as the wax but the two products are far more effective when used together. Allow the PVA to dry for about 20 minutes. When applied properly it will leave a shiny film on the surface of the mold. Like the mold wax, it is important to apply the PVA to all mold surfaces but only in a thin even coat. Imperfections in the PVA will appear as imperfections in the surface of your final part.

5 Leveling Your Mold While is it not required, it s a good idea to level your mold. A level mold allows the epoxy to settle evenly as it sets up and will only add to the quality of your final part. The mold in this example has a flat mold surface and greatly benefits from leveling. If your mold surface is not flat, the benefits of leveling may not be as significant but it will make your mold more stable. The first thing you want to do is to put four pieces of soft clay around the edges of the underside of your mold and then press down on your work surface. Then use a small level to ensure that your mold is perfectly flat. Be sure to level your mold in both the side to side and fore aft directions.

6 EPOXY RESIN WARNING! Curing epoxy generates heat. When contained, a large mass of curing epoxy has a very short pot life, and can generate enough heat to melt plastic and foam, burn your skin and ignite combustible materials. For this reason do not use foam or glass mixing containers. If a pot of mixed epoxy begins an exothermic reaction (heat up), quickly move it outdoors. Avoid breathing the fumes. Do not dispose of the mixture until the reaction is complete and has cooled. Do not fill or cast layers of epoxy thicker than 1/2" - thinner if enclosed by foam or other insulating material. Do not pour into confined spaces. If mixing larger amounts of resin, mix in a flat-bottomed container large enough so that the mixed resin is no more than deep. Instead consider mixing resin in smaller amounts, and using it as you need it. Applying the Epoxy Resin The next step is to apply the epoxy to the mold surface. The epoxy comes in two parts, the resin and the hardener. It is critical to get the proportions of resin and hardener exactly right. The amount of hardener to mix with a portion of resin is 50% by weight. We strongly recommend that you use a gram scale accurate to 0.1g, to measure the exact proportions of resin to hardener. Gram scales are available on our website as well as other internet locations. The first step is to weigh one of the mixing cups that came with your kit and determine its empty weight. In this example the cup weighs 7.8g. Then pour in a small amount of epoxy resin.

7 You only want to put enough resin in the cup to cover the surface of your mold in one thin layer, so it is not very much! Once you have poured the resin in the cup, weigh it again to get the total weight of the cup and resin. In this example, the total weight is 19.6g. Now its time to do a little math to calculate how much hardener we need to add to the cup.

8 We know that the total weight of the cup and resin is 19.6g. We also know that the weight of the empty cup is 7.8g. So to determine the weight of the epoxy resin in the cup, we only have to subtract 7.8 from 19.6 to get 11.8g of epoxy resin in the cup. To determine how much hardener we need, we simply multiply 11.8 times 50% or 0.50 to get 5.9g of hardener. Now if we add the 5.9g of hardener to the total weight of the cup and epoxy of 19.6, we get 25.5g. This will be the total weight of the cup after the correct amount of hardener is added. So put the cup back on the scale and slowly pour hardener into the cup until the total weight is equal to 25.5g. Applying the First Coat of Epoxy Now that you have the correct portions of epoxy resin and hardener in the cup, you are ready to start mixing. Use one of the included brushes to mix the epoxy but before you do, be sure to shake out any loose bristles, as you don t want them to fall into the epoxy. Now mix the epoxy together thoroughly but not too vigorously, as this will unnecessarily add bubbles.

9 Once the epoxy is mixed, brush on a thin layer to the surface of the mold. As you brush the epoxy on, you may find that the epoxy pulls away from the surface of the mold like water on a freshly waxed car. These are the mold release agents doing their job. It is important that you ensure that the entire surface of the mold remains wet with epoxy and that no dry spots are left. This becomes a balancing act between using the minimum amount of epoxy as you can and ensuring that there are no dry spots. Invariably, you are going to have some bubbles in the epoxy. Most of the bubbles will disappear before the epoxy sets up but there is a trick you can do to reduce the bubbles. Using a hair dryer or heat gun set on low, apply a small amount of heat to the epoxy and the bubbles will disappear. Don t over do it as you can cause the epoxy to set up too quickly as well as damage your mold or the layer of release agents.

10 Now you want to set your mold aside and allow the epoxy to get tacky. What does tacky mean? It means that the epoxy sets up enough that while its still soft, you can touch it and no epoxy comes off on your finger. For a thin layer of epoxy at between degrees F, it should be ready in about one hour and 15 minutes or so. Keep in mind that this is just a guide and your results can vary greatly so constantly monitor your epoxy. As a tip, put your used brush in a plastic bag and then into the refrigerator. This will greatly extend the curing time of the epoxy and allow you to reuse the brush for hours. Preparing Your Carbon Fiber Fabric While you are waiting for the epoxy to setup, now is a good time to prepare your carbon fiber cloth for application. The first step is to measure your mold. You are going to want your fabric to be at least in. bigger than the dimensions of your mold.

11 Once you have the dimensions, cut your carbon fiber cloth. You will want to cut out a number of sheets equal to the number of layers you will require for your part. In this example, we are going to use two layers. Depending on your application, you may only need one or more than two. When handling carbon fiber fabric be very gentle. It will unravel very easily and the fabric can become un-aligned. Also, when cutting, carbon fiber dust is generated. While it is not know to be dangerous, it is recommended that you ALWAYS wear gloves, eye protection, and a facemask. The dust is known to cause skin irritation and localized itching. Applying the Carbon Fiber Fabric Before you apply the fabric to your mold you want to be sure that the epoxy is tacky. This is very important as if you apply the fabric too soon, it pull up and create air gaps in the surface of your part. If you are not sure that the epoxy is tacky it is always wise to err on the side of waiting too long instead of not long enough. Once you are sure the epoxy is ready, its time to apply the carbon fiber fabric.

12 Simply align the fabric over the mold and gently apply it to the mold surface. Be sure that your alignment is right as once the fabric touches the epoxy, it won t come off again. While the illustration shows otherwise, it is strongly recommended that you always wear gloves when handling carbon fiber. Once the fabric is down, use your fingers to press the fabric into all the corners and edges of the mold. If the epoxy is tacky, the fabric will stick and hold onto all the surfaces of the mold.

13 Once your satisfied that you have pressed the fabric into all surfaces of the mold, then mix up another small batch of epoxy and apply it to the carbon fiber. Remember that you only want to wet the carbon fiber fabric. You do not want an excessive amount of epoxy to pool on the surface. Now set the mold aside and wait for the new layer of epoxy to get tacky. Applying the Second Layer of Carbon Fiber Fabric Now that the second layer of epoxy has gotten tacky, simply apply the next layer of carbon fiber fabric just as you did the first time, pressing the layer into all the corners of the mold. Once you are satisfied that the second layer of carbon fiber fabric is placed correctly, then mix up another small batch of epoxy and apply to the surface of the carbon fiber fabric. Now for some parts this may be the last layer of epoxy and fabric that you need. All you need do now, is let the part cure overnight and go to the section of this manual called De-Molding. But if you want your part to have extra strength, you

14 could add yet another layer. Much of the strength of a carbon fiber part comes from its thickness, so more layers means more strength (but more weight). But instead of using the expensive carbon fiber fabric for each layer, you can use inexpensive fiberglass. The first two layers of any part should always be carbon fiber but after that you can alternate between fiberglass and carbon fiber. Your kit comes with a length of fiberglass just for this purpose. To add another layer of fiberglass, wait until your latest layer of epoxy gets tacky and apply a layer of fiberglass fabric just as you have applied the carbon fiber. When you re done with the fiberglass, again mix up a small batch of epoxy and apply the final layer to the fiberglass. It s easy to tell when the fiberglass is properly wetted with epoxy, as it will become transparent. Now set the mold aside and allow to cure overnight. De-Molding Now that your part has cured overnight, the epoxy is good and hard. It is essential that he epoxy has been allowed to cure fully at a temperature of 70F or above. If the epoxy is still soft, it will be much harder to remove from the mold and you will damage your part.

15 To remove your part from the mold, simply use your fingers to slowly lift one edge of the part away from the mold. You will hear the edge separate and once it does the rest of the part will just lift out. If your part does not come out easily it could be one of several problems. Either you didn t allow the epoxy to cure fully due to low air temperature or improper mixture of the hardener, or perhaps you didn t apply the mold release agents properly. Another possibility is in the mold itself. If the mold had cut outs or undercuts it would have caused a mechanical lock making it very difficult or impossible to remove your part. Next you want to trim your part. There are a variety of ways to do this but one of the most effective is to use a Dremel tool with a cut off wheel. Be sure to wear eye protection if you use the Dremel!

16 Final Finishing Now that you ve trimmed your part it s almost done. Its strong and light but it lacks one important thing, a nice bright shiny finish. There are several ways to give it a great finish including brushing on a final coat of epoxy. Many people do this but this technique has problems. For one thing, the surface of your part will repel the epoxy and require you put a very thick coat to get coverage. When you do this, the surface will not be even and smooth. This will require sanding and a lot more work. The easier way is to use an automotive-based acrylic clear coat available at any automotive parts store. It s cheap and very effective. Wipe off the surface of your part with a clean dry cloth to make sure the part is clean and then follow the directions on the can to spray a nice even layer of clear coat onto your part. Don t be afraid to lay it on a little thicker than the directions might indicate. You want the final coat to be heavy enough that it leaves a smooth glass like surface on your part. Be advised that these acrylic sprays are nasty! You MUST wear a respirator, eye protection, and gloves in a well-ventilated area.

17 Let your part dry overnight (allow at least two days to fully cure) and the next day you will have a beautiful carbon fiber part that you made yourself! Congratulations, you re done!