Some things I’ve had to learn along the way:
Lams/Tapers
In the world of traditional bowyer craftsmanship, lamination measurements follow a very specific “thick-to-thin” logic to ensure the limbs bend (tiller) correctly.
Breaking Down the Measurements
When you see a lamination described as .100″ with a .001″ taper, it is interpreted as follows:
Butt Thickness (.100″): This is the measurement at the thickest end of the lamination (the end that will be glued at the riser/handle).
Taper Rate (.001″): This is the rate of change per linear inch. For every inch you move away from the butt toward the tip, the wood is ground thinner by exactly one-thousandth of an inch.
Why This Matters for Your Bow
The taper is what creates the “natural” bend of the limb.
Parallel Laminations: These have a .000″ taper (same thickness end-to-end). Using only parallels makes a bow very difficult to tiller and often results in “hand shock.”
Tapered Laminations: By using a .001″ or .002″ taper, you are pre-distributing the stress. The limb gets thinner as it gets further from the riser, allowing the tips to move faster and the limb to bend in a smooth, parabolic arc.
Creating the stack: If you are stacking multiple laminations, bowyers often “sandwich” a parallel lamination between two tapered ones to reach their target draw weight while maintaining a clean limb profile. Learn more about measuring and determining stack thickness to match your desired draw weight. Back to Top
Tillering
Tillering is the process of gradually removing material from a bow’s belly to ensure the limbs bend evenly and reach your target draw weight safely.
1. The Core Stages of Tillering
Tillering typically progresses through three distinct phases:
Floor Tillering: Before stringing the bow, press one tip against the floor while holding the other to check the initial bend.
Long-String Tillering: Use a tillering rope that is longer than the bow to begin pulling it on a tillering stick or tree.
Short-String (Brace) Tillering: Once the limbs bend evenly to roughly half your draw length, switch to a standard-length string to reach full brace height and final draw length.
2. Essential Rules for Success
Never Exceed Target Weight: If you want a 40lb bow, never pull it harder than 40lbs on the tiller. If it reaches 40lbs at only 10 inches of draw, remove more wood before pulling further.
Identify Stiff Spots: Only remove wood from areas that are too stiff; leave the bending sections alone.
Exercise the Limbs: Every time you remove wood, pull the bow 20–30 times to “teach” the wood to accept the new bend before re-checking the tiller.
Go Slow: Removing material is easy, but you cannot put it back. Use a card scraper for fine adjustments in the final stages.
3. Key Measurements to Watch
As you progress, monitor the tiller height—the distance from the string to the belly at specific points (often where the limb meets the riser).
- Positive Tiller: Most archers prefer the top limb to be slightly weaker, creating a gap about 1/8″ to 1/4″ larger than the bottom limb.
- Even Tiller: Often preferred for “three-fingers under” shooting styles. Back to Top
What is a Fadeout?
The Fadeout (or “fades”) is the tapered area at the ends of the riser where the wood gradually thins out to nothing as it meets the limbs.
Why it’s helpful for beginners:
Stress Management: It is the most critical transition point on a bow. If the fadeout is too abrupt or poorly glued, the limbs will often delaminate or snap at this junction.
Lamination Fit: The fadeouts are where the laminations must be perfectly “feathered” to ensure a seamless bond between the stiff riser and the working limb.
Design Precision: Understanding fadeouts helps visualize how energy is transferred from the rigid handle into the flexible limbs. Back to Top
Back vs Belly
In bow building, understanding the difference between the Back and the Belly is the most fundamental concept because wood behaves differently under different forces. Wood fibers are generally stronger in tension than compression.
The Back (Tension Side)
The Back is the side of the bow facing the target.
- The Force: When you pull the string, the fibers on the back are being stretched (tension).
- The Risk: If there is a flaw, a deep scratch, or a grain “run-out” on the back, the fibers can peel up and cause the bow to explode.
- Materials: This is where you place your backing (like sinew, rawhide, or fiberglass) or your most pristine veneer to protect the integrity of the limb.
The Belly (Compression Side)
The Belly is the side of the bow facing you (the archer).
- The Force: When you draw the bow, the fibers on the belly are being crushed together (compression).
- The Risk: If the wood isn’t strong enough to handle the pressure, it will develop “chrysals” (tiny compression fractures) or the limb will take a permanent bend, known as “set.”
- Materials: Dense hardwoods are excellent for the belly because they can withstand being squeezed without collapsing. Back to Top
Stacking
Stacking occurs when a bow’s draw weight increases disproportionately during the final inches of the draw. Instead of a smooth, linear build-up, the bow suddenly feels like it “hits a wall,” becoming significantly harder to pull. Traditional Archery experts note that this is usually a result of bow geometry—specifically when the angle between the string and the limb tip exceeds 90 degrees at full draw.
Why Stacking Matters to Bowyers:
- Draw Length Limits: A bow that stacks at 28″ will feel harsh and uncomfortable for an archer with a 30″ draw.
- Design Precision: Using your tapered laminations (.001 or .002) helps prevent stacking by allowing the limb tips to flex more than the mid-limb, maintaining a better string angle throughout the draw.
- Performance: A bow that doesn’t stack is more “forgiving” and efficient, as it stores energy smoothly rather than just becoming difficult to hold at anchor.
Optimizing the Draw
The key to a “sweet-shooting” bow is a smooth draw that avoids stacking (a sudden, harsh increase in weight at the end of the draw).
- Using Tapered Laminations: By utilizing .001″ or .002″ tapers, you ensure that the limb tips remain active and flexible. This improves the string angle at full draw, preventing the “wall” feeling and creating a much more forgiving shot.
- Actionboo Advantage: The high strength-to-weight ratio of Actionboo allows you to build thinner, lighter limbs that store energy efficiently without the bulk that often leads to early stacking. Back to Top
What is Brace Height?
Brace height is the distance from the deepest part of the grip (the pivot point) to the bowstring when the bow is at rest. In traditional archery, it is also historically known as fistmele—roughly the height of a clenched fist with the thumb extended.
Why It Matters for Your Build:
- Performance vs. Forgiveness: A lower brace height increases the “power stroke,” keeping the arrow on the string longer and generating more speed. A higher brace height is generally more “forgiving,” meaning it is less sensitive to minor errors in your shooting form.
- Noise and Vibration: Finding the “sweet spot” in brace height is the best way to quiet a bow. If the brace is too low, you’ll often hear a loud “slap” or feel excess hand-shock.
- Tuning with Tapers: Since you are using Bending Branch Actionboo or Walnut veneers, your brace height will work in tandem with your limb tapers to determine how smoothly the bow stored energy.
Quick Tuning Tip:
Most traditional bows perform best within a range of 7.5″ to 8.5″. Start at the lower end and add twists to your bowstring to “raise” the brace height until the bow sounds like a quiet “thump” rather than a loud “crack”. Back to Top