Kayaking is becoming an increasingly popular activity for outdoor recreation and transportation. For paddlers looking to embark on extended trips or handle challenging waters, having a stable and durable kayak with ample cargo capacity is crucial. One excellent option is to build your own custom Greenland style tandem kayak, which offers key advantages over other kayak types.
The Greenland design, modeled after traditional Inuit qajaqs, is characterized by its elongated, V-shaped hull which provides exceptional tracking ability and stability. Meanwhile, opting for a two-seater configuration allows for greater gear storage, shared paddling duties, and added safety offshore. Together, these features make Greenland tandem kayaks ideal for multi-day excursions and unpredictable conditions.
This comprehensive guide covers critical considerations in choosing, constructing, and outfitting a stable and robust Greenland tandem kayak. Key topics include utilizing proper hull materials and reinforcements, distributing weight for optimal trim, installing bulkheads, enhancing on-water stability, and other vital techniques. With some effort and care taken during the building process, the result will be a versatile hand-crafted kayak ready for adventure across miles of open waterways.
Choosing the Right Kayak Design
Advantages of a Greenland Style Kayak
The Greenland style kayak gets its name from the traditional single-seat models used by Inuit hunters in Greenland. Some key features that make this type of kayak ideal for stability include:
- Elongated, narrow hull shape optimized for straight tracking and maintaining course. The V-shaped hull cuts smoothly through water.
- Low rear deck and semi-rounded bottom provide excellent primary and secondary stability. The paddler sits low in the hull for a lower center of gravity.
- The lack of a prominent keel and rounded bottom allow for quick, agile turning maneuvers.
- The deck is high and wide in the front and middle for cargo storage and flotation.
- Designed for use with a double bladed paddle, allowing powerful forward strokes for momentum.
In addition to stability and tracking, the Greenland style kayak provides excellent protection from the elements. The high front deck shields the paddler from wind and waves, while the splash guard prevents water from coming in through the cockpit. For two paddlers, this offers safety and comfort over long journeys.
Benefits of a Tandem Kayak
Tandem kayaks are designed with two seats, allowing two adults to paddle the kayak together. For longer trips, having an extra paddler provides several advantages:
- Increased cargo capacity to pack more gear and supplies. The rear and front hatches can hold duffel bags, camping equipment, and other cargo.
- Ability to share the work over long distances, avoiding fatigue. Paddlers can switch positions or paddle in unison.
- More potential paddling power for navigating through challenging conditions like strong winds and currents.
- Added safety, allowing one paddler to steady the kayak if the other needs a rest.
- Wider beam provides more interior space for legs and gear.
For extended kayaking expeditions covering dozens of miles, tandem kayaks make the journey much more manageable compared to a solo kayak. Two adults can also more easily carry the kayak when portaging between waterways.
Weight Distribution for Stability
Distributing weight appropriately fore, aft, and laterally is crucial for maintaining stability in a tandem kayak. Poor weight distribution can make the kayak prone to tipping and capsizing. Here are some key tips for optimizing weight placement:
Importance of Fore/Aft Weight Distribution
Ideally, the center of gravity should be slightly aft (toward the rear) of the kayak’s midpoint. Sitting too far forward can cause the bow to ride low and ‘plow’ through the water, reducing stability. Sitting too far aft can cause the stern to sink and the bow to rise out of the water.
- Take note of the manufacturer’s specified dimensions for the ideal fore/aft weight distribution. Adjust the foot braces and seat positions accordingly.
- Use the bulkheads to stow heavier gear close to the midpoint to avoid submerging the ends. Keep the bow and stern compartments light.
- When paddling in strong headwinds, have the heavier paddler sit in front to keep the bow down. In tailwinds, they should sit aft.
Lateral (Side-to-Side) Weight Distribution
It’s important to avoid leaning too far to one side, which can put that edge dangerously low in the water.
- Keep centered with weight evenly balanced between sides. Avoid leaning to reach for gear.
- Position heavy items like coolers along the centerline. Gear stowed to one side can make the kayak list.
- If paddling solo, sit in the center to even out the weight.
- When seated together, the heavier paddler should take the center position.
Weight Distribution in a Tandem Kayak
Distributing weight effectively is especially crucial with two adults seated together.
- Try to match the bow and stern paddler weights as closely as possible. Wildly unequal weights can make balancing tricky.
- The heavier paddler should always take the center rear position. This keeps the lowest point near the midpoint.
- Gear weight should be distributed evenly on both sides. Avoid overweighting one side.
- Communicate weight adjustments with your partner to keep the trim optimized.
Building Techniques for Stability
The way a kayak is constructed can significantly impact its stability and durability for extended trips in unfavorable conditions. Here are some kayak building techniques that promote stability:
Reinforcing the Hull
The hull skin bears all the forces of water pressure and impacts, so it must be strong and rigid. Use these techniques when assembling the kayak:
- Use high-quality marine plywood or ultra-high-molecular-weight (UHMW) polyethylene sheets. Avoid porous, flexible materials.
- Fiberglass cloth adds tremendous rigidity and impact resistance to the hull. Epoxy multiple layers of fiberglass inside and out.
- For plywood construction, avoid gaps between panels. Stagger joints and coat with epoxy fillets for smooth load transfer.
- Use supporting stringers, knees, and bulkheads running the length of the interior hull cavity. This stiffens the entire structure.
Keeping the Center of Gravity Low
The lower in the hull the combined center of gravity of the load is, the harder it is to capsize a kayak. Some ways to achieve a low center of gravity:
- Use a rounded hull shape that fills with water inrollover, lowering the center of buoyancy.
- Minimize deck height and cockpit coaming height. The paddler sits as low in the hull as possible.
- Carry weight as low and as centered as possible. Ballast the bilge if needed.
Strategic Internal Bulkhead Placement
Bulkheads involve vertical partition walls inside the hull cavity. They improve stability by:
- Preventing sloshing of water from end to end.
- Allowing you to position heavy objects low and centered.
- Adding hull stiffness and compartmentalization.
When installing bulkheads:
- Place one midway between the bow and stern for central weight.
- Use watertight hatches and bulkheads to create flotation compartments.
- Coat edges thoroughly with epoxy for waterproofing.
Materials, quantities, and usage
|Marine plywood sheets (1/4″ thickness)||8||Hull skin|
|Fiberglass cloth (6 oz)||10 yards||Reinforcing hull|
|Epoxy resin||2 gallons||Bonding hull panels and fiberglass|
|Polyurethane varnish||1 quart||Sealing the wood|
|Silicone sealant||1 tube||Waterproofing seams|
|Foam sheets (1/2″ thickness)||4||Cockpit coaming|
|Polyethylene foam sheets (1/4″)||2||Bulkheads|
|Acrylic sheeting (1/8″)||1 sheet||Hatch covers|
|Nylon strapping||20 ft||Tie downs|
|Brass D-rings||12||Mounting tie downs|
|Wood trim pieces||See plans||Frame supports|
|Carbon fiber tube||1 (1″ dia)||Bow stem|
|Fiberglass tube||1 (1″ dia)||Stern piece|
|Marine grade hardware||See plans||Rudder assemblies, foot braces|
|Spray skirts||2||Cockpit covers|
Load Capacity Considerations
One of the biggest advantages of a tandem kayak is the expanded carrying capacity over a solo boat. However, it’s important to choose a design with ample weight capacity for the combined weight of passengers and cargo. Here are some guidelines:
Allow Ample Weight Margin
The total weight limit should substantially exceed the total of:
- Combined paddler weights
- Weight of all essential gear like food, water, camping equipment
- Safety margin of at least 10-20% of total paddler weights
This avoids exceeding capacity if some extra gear is added later.
Base Weight on Maximum Load
The manufacturer’s weight capacity is typically listed as a maximum. For optimal stability, only load up to 60-80% capacity for average expeditions. The maximum capacity should only be used in emergencies.
Distribute Weight Evenly
Don’t place all the heavy gear in just the bow or stern. Distribute weight evenly fore and aft of the cockpit area to avoid capsizing.
Consider Weight of Non-Essentials
Optional items like electronics, fishing gear, etc can add up quickly. Decide what is essential to minimize excess weight.
With good design considerations and testing, a tandem kayak can safely handle 500-600+ lbs of cargo weight for multi-day excursions in remote areas.
Enhancing Stability on the Water
Once on the water, the paddling technique and accessories used can further enhance stability in challenging conditions:
Proper Paddling Technique
Maintaining good form is crucial for controlling a stable heading and preventing tipping.
- Keep upright posture with core engaged so body movements don’t destabilize the kayak.
- Use core muscles to rotate torso as one unit. Avoid bending at waist.
- Brace paddle against boat to increase leverage and stability when waves hit from the side.
- If paddling solo, take slightly wider strokes on each side to keep on track.
- Time strokes with partner to apply power smoothly without rocking boat. Communicate adjustments.
Maintaining a Low Center of Gravity
Keep the combined center of gravity of passengers, gear, and kayak as low as possible:
- Sit with hips below rim of cockpit for maximum stability. Thigh braces can help keep legs low.
- Avoid raising the center of gravity by standing or shifting weight suddenly. Move slowly and smoothly.
- If needed, add ballast weight bags low in the bilge to lower the center of gravity.
Using a Rudder System
Rudders are useful for stabilizing course and correcting direction in wind and waves:
- A foot-controlled rudder aids steering from the rear without destabilizing leaning strokes.
- The rudder adds directional stability akin to a keel on a sailboat.
- Trailing rudders pivot up against the stern to avoid damage when beaching.
With practice, a well-designed tandem kayak provides a stable, confidence-inspiring platform for paddling efficiently across all kinds of waterways.
For kayaking enthusiasts seeking to embark on extended multi-day trips and handle challenging seas, building a custom tandem Greenland style kayak offers many advantages over purchasing a standard recreational kayak. The Greenland hull shape provides excellent stability and tracking, while a two-seater tandem design allows for greater cargo capacity, shared work between paddlers, and added safety.
By carefully considering weight distribution, internal compartments, reinforced hull composite construction, and stability-enhancing accessories like rudders, a durable hand-built tandem kayak can comfortably manage remote expeditions in demanding conditions. Do some research to find a proven kayak design, and take the time to carefully complete each construction step. With some dedication and care, you’ll be rewarded with a robust vessel ready to carry you and your partner across miles of open water.
The finished kayak will provide many seasons of adventurous trips paddling in sync with nature. With each passing mile, you’ll appreciate the quality and personalized touches you put into building your own custom tandem Greenland kayak from scratch.