Crafting A Fiberglass Recurve Bow

Making a fiberglass recurve bow is a challenging project, even for experienced bowmakers. The process involves creating a laminated bow with a wooden core and a fiberglass exterior. The weight of the bow will depend on the thickness of the core and the type of fiberglass used. To begin, you'll need to gather your materials, including thin strips of wood for the laminations, Bo-Tuff fiberglass, epoxy, and tools for shaping and sanding. You'll also need to construct a Laminating Heat Box and a Bow Press to glue and shape your bow.

Constructing the laminating heat box and bow press

Laminating Heat Box:

The laminating heat box is an insulated wooden oven that will cure your bow at the appropriate temperature. Here's how to construct it:

• Source the required materials: plywood, light fixtures, lightbulbs, electrical wire, a thermostat, and screws or glue for assembly.
• Cut and assemble the plywood to form an insulated box that can accommodate the size of your bow. Ensure it is slightly larger than your bow to allow for even heating.
• Install the light fixtures and bulbs inside the box. These will generate the heat needed to cure the epoxy.
• Wire the thermostat to control the temperature within the desired range. This ensures your bow is cured properly without overheating.

Bow Press:

The bow press is responsible for giving your bow its distinctive shape. Here's how to create it:

• Determine the type of bow you want to build (longbow, reflex/deflex, or recurve) as this will influence the design of your press.
• Gather the necessary tools and materials, including plywood, a strip of Formica or Bo Tuff, brackets, nuts, bolts, and wood spacers.
• Cut the plywood to form two halves of the press, ensuring one section is longer than the bow to accommodate the air hose and provide pressure to the limb ends.
• Secure and even out the two halves, focusing on levelling and smoothing the front or belly portion of the press.
• Attach the strip of Formica or Bo Tuff to this smoothed surface to create a consistent, smooth finish for your bow.
• Install the brackets that will hold the two halves of the press together under pressure. Place them at least one inch apart, leaving space for the bow, pressure strip, and air hose.
• Mark and drill holes for the nuts, bolts, and brackets, then assemble them to complete your bow press.

With your laminating heat box and bow press constructed, you're now ready to cure and shape your fiberglass recurve bow. Remember to refer to detailed instructions or seek expert advice if needed during the building process.

Gluing the bow together

To glue your bow together, you will need to construct two items: a laminating heat box and a bow press. The heat box is an insulated wooden oven heated by lightbulbs and controlled by a thermostat to maintain the correct temperature for curing your bow. The bow press will give your bow its distinctive shape.

First, apply the epoxy to your laminations and fiberglass. Then, place your bow limbs into the press and put the press inside the heat box. Leave the bow to "cook" for three to four hours to set the epoxy and create a strong bond.

Once your bow is out of the heat box and cooled down, you can cut, shape, sand, and finish it to your liking.

Cutting, shaping, and finishing the bow

Once your bow is out of the heat box and cooled down, you’re now ready to cut, shape, sand and finish it. The entire process is covered in detail in our instruction material, but this is where your personal touch will be applied to the bow. Your specific brand of craftsmanship and eye for detail in sanding the bow and shaping your riser (handle) will bring the bow to life.

Now, for the cutting, shaping, and finishing process:

First, cut the bow to the desired length, typically around 62-64 inches for a full-size bow. You can use a PVC pipe cutter or a survival multi-tool saw to cut the bow to the desired length.

Next, you'll want to shape the bow. This involves using a drum sander to smooth out the edges and shape the bow to the desired curve. Take your time with this step, as it will greatly impact the performance and aesthetics of your bow.

After shaping, it's time to finish the bow. Start by sanding the bow with a fine-grit sandpaper to smooth out any rough areas. You can also use a wood-burning tool to add decorative touches or personalise your bow. Finally, you can apply a coat of varnish or paint to protect the wood and give it a polished look.

Once the finishing touches are complete, you can string your bow and test it out! Remember to practice proper form and safety techniques when using your new fiberglass recurve bow.

Binding the fiberglass core

To bind the fiberglass core, you will need to start by taping together all of your rods so that you have two cores, each made from two rods taped side-by-side. You can use any type of tape for this process, but it is important to make sure that the tape is secure and will hold the rods together tightly.

Once you have your two cores, you will need to measure and cut your 1/2-inch PVC pipe insert. This insert will be placed at the end of your bow and will give you an idea of how much room you have inside the bow for the cores. Line up the rods so that the tips end at the point where the insert starts.

The standard rods are not long enough to go all the way down the bow by themselves, but this is okay because we are going to layer them on top of each other. As you can see in the image below, if one of our rod pairs is touching the bottom of the 1/2-inch PVC (the one we haven't inserted yet), we can place the other rod pair about a foot down the line.

We line up our second rod pair so that it reaches the other end of the bow, also accounting for the insert, and tape this whole system together. This layered 4-rod system should be about 58 inches long. We know this because our pipe is 62 inches, and it has (or will have) the smaller 2-inch inserts on either end. These rods will eventually sit inside the bow pipe in between the space left by the 2-inch inserts on either end.

Now that you have your core, stuff it into the bow pipe from the end that does not yet have the 1/2-inch piece in it. Once you get to the last inch of the rod sticking out, use a pipe, stick, or socket wrench extension to push the rods the rest of the way into the pipe.

Sanding the insert edges

When sanding the insert edges, it is important to focus on creating a smooth and even taper. This can be achieved by using a consistent sanding motion and applying even pressure along the edge of the piece. It is also crucial to use the appropriate grit sandpaper for the job. Starting with a medium-grit sandpaper, you can gradually increase the grit size to achieve a finer finish. Taking your time with this step will ensure that the inserts slide in smoothly and securely.

Additionally, it is important to pay attention to safety when sanding. Wearing protective gear, such as gloves and eye protection, will help safeguard against any injuries. Sanding can create dust and small particles, so it is recommended to work in a well-ventilated area or use a dust mask to avoid inhaling any debris. By taking the necessary precautions, you can ensure a safe and effective sanding process.

Once the insert edges are adequately sanded, you can move on to the next step of hammering the tips into the hollow ends of the 3/4-inch pipe. This will create a solid base for your fiberglass bow and bring you one step closer to completing your project.

Frequently asked questions