Stress Cracks: Signs Your Recurve Bow Needs Attention

Stress cracks in a recurve bow can be identified by running a cotton ball up and down the limbs of the bow—if the cotton ball snags, this indicates a crack. Cracks can also be identified by sight, and sometimes by touch. Stress cracks are usually vertical and often appear on vintage bows, but can also be horizontal. Horizontal cracks are more dangerous and can cause the bow to fail. If you identify a crack in your bow, you can try to repair it with resin, super glue, or nail polish, but this may not work. Some people recommend retiring the bow and hanging it on the wall instead.

Stress cracks are common in vintage bows

Stress cracks are a common issue for vintage bows, especially in the glass finish. These cracks are usually the result of factory overdrawing of bows or exotic wood handles drying out after completion. They can also be caused by leaving a bow strung and standing in a corner, or by incorrect stringing.

If you notice a crack in your vintage bow, it's important to assess the severity. Vertical stress cracks are generally considered safe to shoot with, and many vintage bows with these cracks are still in use today. However, horizontal cracks are considered "show stoppers" and indicate that the bow should be retired.

If you're unsure about the severity of a crack, it's recommended to consult with experts or bowyers who can advise on the best course of action. Some people choose to repair stress cracks with super glue or resin, but this is not always effective and may not be worth the risk.

To check for damage to your bow, you can rub a cotton ball up and down the limbs. If there are any cracks, the cotton ball will snag on them. Additionally, twisted limbs can be a sign of damage, and this can often be corrected by twisting the limb tip in the opposite direction and leaving the bow strung for a couple of weeks.

Horizontal cracks are dangerous

Horizontal cracks, also known as stress cracks, are considered more dangerous than vertical cracks. Vertical cracks, or stress fractures, typically do not affect the performance of the bow and are usually only a cosmetic issue. However, it is important to monitor vertical cracks as they can sometimes lead to more serious issues. If a vertical crack starts to widen, lift, or travel, it may be a sign that moisture has penetrated the wood core, compromising the integrity of the glue and wood.

To identify if your bow has horizontal or vertical cracks, examine the direction of the cracks in relation to the limb. Horizontal cracks run across the limb, while vertical cracks run parallel to it. If you are unsure, it is best to seek the advice of an expert or a bowyer. They can help you assess the severity of the cracks and determine if the bow is safe to use.

It is also recommended to regularly inspect your bow for any signs of damage, such as cracks or delamination. This will help you identify potential issues early on and prevent accidents. Additionally, proper storage and maintenance of your bow can help prevent the formation of cracks and other types of damage.

Vertical cracks are less of a concern

Vertical cracks, or stress cracks, are generally less of a concern than horizontal cracks. They are usually only cosmetic and do not impact the performance of the bow. However, it is still important to monitor them for any signs of worsening. If the cracks start to travel or raise, it could be a sign that the wood core has been compromised by moisture, which can lead to limb failure.

Stress cracks typically take time to develop and can be caused by temperature changes or the natural ageing process of the bow. They can also be caused by excessive shock, such as dry firing or firing too light an arrow. To prevent this, it is recommended to use arrows with a weight of at least 6 grains per pound of bow weight.

While vertical cracks may not require immediate repair, some people choose to fill them with resin, super glue, or nail polish to improve the appearance of the bow and prevent the cracks from spreading. Others suggest using a piece of masking tape over the crack to monitor its progress.

It is important to note that while vertical cracks are generally less concerning, they should not be completely ignored. Regular inspection and maintenance of your bow are crucial to ensure its longevity and your safety.

Delamination is a common cause of cracks

Delamination can be caused by several factors, including poor-quality materials, improper construction techniques, extreme temperatures or humidity, and impact or stress damage. For example, using low-quality wood that is prone to warping or rotting, or using incompatible fiberglass or carbon fibre with the adhesive, can lead to delamination. Failing to properly heat and press the bow during construction can also cause the layers to separate over time.

Exposure to extreme temperatures or humidity can weaken or break down the glue between the layers, leading to delamination. Leaving a bow in a hot car trunk or a damp basement can cause the layers to separate. Impact damage, such as dropping the bow or hitting it against a hard surface, can also cause the layers to separate. Repeatedly drawing the bow beyond its recommended weight or using arrows that are too heavy can cause stress damage and lead to delamination.

To prevent delamination, it is important to use high-quality materials and proper construction techniques. Storing the bow in a cool, dry place and avoiding extreme temperatures or humidity is crucial. Regular inspections and maintenance can also help catch any damage early and prevent severe delamination.

You can repair cracks with resin, glue, or nail polish

If you spot a crack in your recurve bow, don't panic. Small cracks are common in vintage bows and are usually safe to shoot. However, it's important to repair the crack to prevent it from growing and causing further damage. You can repair cracks with resin, glue, or nail polish.

Here's a step-by-step guide to repairing cracks in your recurve bow:

• Clean the Surface: Start by cleaning the area around the crack to remove any dirt or debris. This will ensure that the tape or glue adheres properly to the surface.
• Tape the Crack: Use masking tape or painter's tape to cover the crack. This will help contain the glue or resin and prevent it from spreading to unwanted areas.
• Cut a Slit in the Tape: Use a sharp blade to carefully cut a slit in the tape, following the line of the crack. This will allow the glue or resin to penetrate the crack.
• Fill the Crack: Use laminate glue, fiberglass resin, or thin super glue to fill the crack. You can use a Popsicle stick or a small brush to apply the adhesive. It's okay if some glue squeezes out; you can sand it down later.
• Let it Dry: Once the crack is filled, let the glue or resin dry completely. This may take up to 24 hours, depending on the adhesive you use.
• Sand the Surface: After the glue or resin has dried, use fine-grit sandpaper (400-600 grit) to sand the surface and smooth out any excess adhesive. Remove the tape and check that the crack is completely filled. You can repeat the taping, filling, and sanding process if needed.

It's important to note that while repairing hairline fractures can help extend the life of your bow, it's always a good idea to monitor the cracks closely. If the cracks start to travel, widen, or lift, it may indicate a more serious issue, and the bow may need to be replaced.

Additionally, keep in mind that some cracks may be more than surface-level and could indicate a deeper problem. If you're unsure about the severity of the crack or how to repair it safely, it's best to consult a professional bowyer or a reputable archery shop for advice.

Frequently asked questions