Troubleshooting Floor Tillering to Final Draw Curve: Diagnosing and Fixing Problems
As a traditional bowyer, I often find myself knee-deep in shavings and bow limbs, wrestling with the intricate dance of wood and tension. One of the most exhilarating yet frustrating phases in crafting a bow is floor tillering. The journey from a rough-cut stave to a beautifully tillered bow ready for shooting is full of twists and turns. Today, I’m working through troubleshooting the floor tillering process, offering my personal insights and practical solutions for common issues that can crop up.
Understanding the Basics of Floor Tillering
Before we look at the troubleshooting portion, let me briefly outline what floor tillering is. This process involves gradually shaping the limbs of your bow while maintaining a balanced draw curve. The goal is to create a bow that bends uniformly, allowing for optimal performance and a smooth release.
I typically take my time on this, using a dedicated space in my workshop that’s set up specifically for tillering. I aim to achieve a consistent draw weight that matches the bow's intended use, whether it’s for hunting, target shooting, or just plinking in the backyard.
Common Problems in Floor Tillering
Even with care and attention, problems can arise. Here are the most common issues I’ve faced during floor tillering, along with ways to diagnose and fix them.
1. Uneven Draw Weights
Diagnosis: If one limb feels significantly stiffer than the other during draw, you’re likely dealing with uneven draw weights.
Fix: Start by measuring draw weight at various increments (e.g., 5 lbs intervals) until you reach your target draw weight. Use a simple scale for this. If there’s a discrepancy, you’ll want to remove material from the stiffer limb. I usually use a rasp or a spokeshave for this.
Tip: Keep an eye on limb thickness throughout this process; it’s easy to overdo it. Maintaining a consistent thickness across both limbs is vital.
2. Unwanted Reflex or Deflex
Diagnosis: If the bow limbs curve back too much (reflex) or bend forward (deflex) when strung, it can lead to performance issues or even failure.
Fix: Check your limb profile—sometimes a change in wood moisture or grain can affect how the bow behaves. If your limbs are exhibiting reflex, consider removing material from the belly (the side facing you when shooting) and retillering. For deflex, it may be necessary to adjust the tips or remove material from the back.
3. Twists in the Limbs
Diagnosis: A twist manifests when one limb appears to spiral instead of bending uniformly. This usually happens due to uneven growth rings or inconsistencies in the wood. Fix: You can often correct this by carefully sanding or planing the limb that twists. It may take several adjustments, but don’t lose heart. I’ve had to take this step multiple times, and patience is key.A Practical Approach to Troubleshooting
To help visualize the troubleshooting process, I’ve created a simple comparison table based on my experience. It captures common issues and suggested solutions during floor tillering.| Common Problem | Diagnosis | Solution |
|---|---|---|
| Uneven Draw Weights | One limb feels stiffer than the other | Measure draw weight, remove material from stiffer limb |
| Unwanted Reflex or Deflex | Limbs curve back too much or forward | Adjust belly or back, retillering as needed |
| Twists in the Limbs | Limbs spiral instead of bending uniformly | Sanding or planing the twisted limb |