[JoeF]

Development note regarding possible loops at both ends of rigging crosslines:

Prompt:
How do I whip? My thought on this whipping deal: with a needle maybe one could poke or thread under and over after say two surrounds and then cyclically continue such; this seems like a way to cinch tension as the whipping continues. Though it puts little humps and thus is not as neat as the smooth simple surrounding method. A cousin way might be this: use two working ends of a whipping line; begin with a snug shoe-tie first part; then wrap both working ends twice around the main lines that were folded over to make the loop. Then tie a first shoe-tie step again, then wrap both working lines twice again, then cycle the same method for a good distance; then finish. A variation that may have merit: Notice that whipping simply allows an unwhipping if a portion is cut; to mitigate such: whip one surround and tie a firm square knot; cut the thread; do another whip and square knot; cut. Then repeat a series of short wraps like that with its knot. Each knot is then fully separate from other knots. A cutting of one whip-knot scene still leaves all the other whip-knot deals in place. Tell about the surgeon's knot. And also: on the multiple modular knot-whip deal: maybe a drop of super glue? And then to finish: maybe a shrink wrap tube segment to keep chafe and dust control? Same as we just discussed, but consider wetting the whipped-knotting section with silicon forming a no-dust-entry scene. The application on TPHG rigging crosslines in a beach salt-spray sandy environment with lots of sun is the target application.

Response:
Given the target application for TPHG rigging crosslines in a beach salt-spray sandy environment with lots of sun, the method you've been developing with whipping, silicone sealing, and shrink wrap is highly relevant. In this scenario, the goal is to ensure the crosslines are not only secure and durable but also resistant to the harsh elements like UV radiation, abrasion from sand, saltwater corrosion, and sunlight degradation.

Key Considerations for TPHG Crosslines:

• Salt Spray and Corrosion: Saltwater and salt spray can degrade materials over time, especially lines or threads with exposed fibers. You’ll want to fully protect the whipped areas from moisture and salt penetration.
• Sandy Environment: Sand particles can work their way into the fibers of the line and the whipping, causing abrasion and weakening the materials. A sealed whipping would prevent this.
• UV Exposure: Constant exposure to sunlight, particularly UV rays, can weaken many materials, especially synthetic ones. The whipping needs to be protected with UV-resistant coatings or covers.
• Flexibility and Strength: The crosslines will be subject to tension and flexing during flights, so the whipping and sealing materials need to maintain flexibility without becoming brittle.

Adapted Whipping, Sealing, and Protection Process for TPHG Crosslines:

• Modular Whipping with Surgeon’s Knot:
  - Start by whipping the crosslines at key stress points where loops are formed. Modular whipping (as previously discussed) would allow for localized repairs if needed without undoing the entire section.
  - Use UV-resistant thread or line for whipping, such as UV-treated polyester or Dyneema® thread (ultra-high-molecular-weight polyethylene) for maximum durability in sunny environments.
• Apply Super Glue:
  - After tying each modular whipping section with a surgeon’s knot, add a small drop of marine-grade super glue (resistant to water and UV light) to lock the knots securely. This prevents any loosening due to moisture or friction.
• Wetting with Silicone:
  - Once all whipping is complete, apply marine-grade silicone sealant to cover the entire whipped area. The silicone will:
  - Seal against saltwater and salt spray, preventing the line from becoming waterlogged or salt crystals from accumulating.
  - Create a dustproof barrier, so sand won’t infiltrate the fibers and cause abrasion.
  - Remain flexible, so the whipping remains pliable.
  - Curing time: Allow the silicone to fully cure. This may take several hours depending on the thickness applied. A thin coat may be best for flexibility, but make sure it covers all the knots and threads.
• Shrink Wrap for Extra Protection:
  - Once the silicone has cured, slide a marine-grade shrink wrap tube over the whipped section. This adds:
  - UV protection: The shrink wrap protects the silicone and underlying fibers from prolonged UV exposure, which can degrade many synthetic materials.
  - Abrasion resistance: The shrink wrap provides a smooth, durable surface that reduces the chance of sand or grit wearing down the whipping or crossline fibers.
  - Neat finish: The shrink wrap gives the entire whipped section a tidy, clean look and prevents loose threads from fraying over time.
  - Use a heat gun or another source of gentle heat to shrink the tube snugly over the silicone-coated section, making sure not to overheat and damage the underlying material.
• Final Seal with Marine-Grade Silicone Spray: *(Optional)*
  - For additional protection, you could apply a final light coating of marine-grade silicone spray over the shrink wrap and nearby exposed parts of the crossline. This spray will:
  - Add an extra waterproof layer.
  - Repel sand and dust from sticking to the surface.
  - Ensure a UV-protective film over any parts of the crossline that might be exposed.

Pros of This Method:

• Extreme Weather Durability: Combining silicone sealing with shrink wrap offers double protection against saltwater corrosion, sand abrasion, and UV damage.
• Modular Repair Capability: The modular whipping approach allows for localized repairs if a section wears out without needing to redo the entire rigging.
• Waterproofing and Flexibility: Marine-grade silicone ensures the loops and knots stay dry, preventing rot or degradation from water. The flexibility of silicone ensures the whipping remains pliable.
• Long-Term UV Protection: Shrink wrap and silicone are both highly UV-resistant, protecting the crosslines from sun damage and extending the life of the rigging.

Cons:

• More Time-Intensive: Applying both silicone and shrink wrap, followed by curing and shrinking, adds time to the process compared to simple whipping.
• Potential Weight: Depending on how much silicone and shrink wrap you use, this might add a little extra weight to the crossline rigging.
• Maintenance Required: Over time, the silicone and shrink wrap might need reapplication or replacement, particularly in extreme environments where constant sun and sand are present.

Final Thoughts for Beach Environment TPHG Crosslines:
This approach offers a strong balance between durability, flexibility, and protection from harsh environmental factors like salt, sand, and sun. While it takes a bit more effort initially, the result should be a much longer-lasting set of crosslines that are better protected against corrosion, UV degradation, and general wear and tear.

User: I was wondering if weaving a double thickness into the contact region would mitigate the vulnerability.

Assistant: Yes, weaving a double thickness into the contact region can significantly mitigate vulnerability and enhance the durability of a loop under tension. Here’s how this approach can be beneficial:

Benefits of Weaving Double Thickness

1. Increased Strength:
- A double thickness provides greater tensile strength in the contact region, distributing the load over a larger area and reducing the risk of material failure.

2. Improved Wear Resistance:
- With more material in the contact area, there’s a greater buffer against abrasion and wear caused by friction against the resisting structure. This can extend the lifespan of the loop.

3. Load Distribution:
- The double thickness helps to distribute the forces exerted on the loop over a wider area, which can reduce the concentration of stress at any single point, thereby minimizing the risk of failure.

4. Enhanced Stability:
- Weaving additional material into the contact region can stabilize the loop, reducing slippage and movement. This is particularly important in applications where the loop may be subject to dynamic loads.

5. Resistance to Compression:
- A thicker contact area is better equipped to resist compression when the loop is under load. This helps to maintain the integrity of the loop and prevents it from deforming or kinking.

Considerations

- Weight and Bulk:
- Adding double thickness can increase the weight and bulk of the loop, which may be a concern depending on the application. It’s essential to balance durability with weight constraints, especially in applications like hang gliding.

- Material Selection:
- Ensure that the materials used for the double thickness are compatible and have similar properties to prevent uneven wear or failure.

- Manufacturing Complexity:
- Weaving a double thickness may complicate the manufacturing process. It’s essential to consider whether this added complexity is worth the benefits in strength and durability.

Conclusion

Incorporating a double thickness into the contact region of a loop can be an effective way to enhance its performance under tension, particularly in demanding environments like the one you're targeting for your TPHG rigging crosslines. This approach will likely improve durability and reduce the likelihood of failure due to wear and stress concentration. Regular inspections and maintenance will still be important to ensure long-term reliability, but this strategy can help you create a more robust rigging system.

[JoeF]

...

User: Another means for the contact-point doubling: Fold standing line once, then fold that fold again; then whip the doublings and the folded run to the standing line.

Assistant: This method adds extra thickness to the contact point by folding the standing line twice before whipping it to secure the folds. Here’s how this approach can improve loop strength and durability:

Advantages of This Method

1. Doubling the Layer:
- By folding the line twice, the contact point now has two layers of material where the loop meets the load, which increases the tensile strength and spreads the load more evenly, reducing stress at the contact point.

2. Enhanced Durability:
- The doubled layer helps protect against wear and abrasion, offering redundancy if one strand starts to weaken over time.

3. Compact Strength:
- This method provides more strength at the contact point without adding too much extra material. The whipping holds the folds in place securely, creating a strong section to resist tension and friction.

4. Versatility:
- This technique can be used with a variety of ropes, cords, or lines, making it suitable for different applications, including the rigging crosslines of your TPHG in harsh beach conditions.

Considerations

- Slight Bulk Increase:
- Folding the line twice adds some bulk at the loop, but the added strength and protection can be worth the slight increase in size.

- Whipping Precision:
- The whipping must be tight and well-done to keep the layers from slipping over time. Loose whipping can reduce the effectiveness of the doubled layers.

Conclusion

Folding the line twice before whipping adds a second layer of material at the contact point, improving strength and durability. This approach can be particularly useful in high-stress environments like your TPHG’s rigging, where exposure to salt, sand, and sunlight can cause wear. Adding silicone or shrink wrap as additional protection can further enhance the longevity of the loop.

====

User: If first one takes the standing line of a braid with parallel core and doubles backs into the core under the braid to get say 10 inches of doubled run and then folds that doubling for making a loop followed by significant whipping, then the contact point for loading will see doubled strength line.

Assistant: Yes, the method you're describing creates a loop with a doubled line at the contact point, which effectively doubles the strength in that area, reinforcing the loop where the load is applied. Here's how this works:

Process Breakdown:
1. Doubling the Line into the Core:
- First, you take the standing line (the main part of the cord) of a braid with a parallel core and insert it back into the core under the braided sheath for around 10 inches. This action creates a doubled run inside the cord itself.

2. Folding for Loop Creation:
- You then fold this doubled section to create the loop. Now the loop is made from two layers of line, both running through the contact point where the loop will bear the load.

3. Whipping:
- Significant whipping is applied at the base of the loop, securing the doubled section and the folded line in place. This prevents the loop from unraveling and ensures the tension is evenly distributed across the doubled strands.

Benefits:
- Doubled Strength at the Contact Point:
- The loop will have two strands of line passing through the load-bearing contact point, effectively doubling the tensile strength at that point compared to a single strand.

- Even Load Distribution:
- By doubling the line and securing it with whipping, the load is shared between the two strands, reducing the chance of failure due to excessive stress or abrasion at the contact point.

- Reinforced Loop:
- The whipping locks the doubled section in place, providing additional security and reducing the chance of the loop slipping or losing integrity under tension.

This method is particularly useful in high-tension applications, like rigging, where you want to increase durability and load capacity without adding extra hardware. It also helps extend the life of the loop by spreading out the forces and reducing stress concentration at any single point.

Filler tease: HERE

[dhmartens]

The AI is responding:
Yes, you can construct a hang glider with a 3D printer:
Design
You can design a glider to meet certain criteria, such as being easy to assemble, made of basic filament, and able to glide. You can also consider the glider's target, like its maximum weight or landing speed.
Printing
The time it takes to print a glider depends on the size of the glider and the 3D printer being used.
Assembly
The assembly process for a 3D printed glider can take a few minutes, but you should allow time for the glue to dry.
Materials
You can use a 3D printed frame for the wing, a paper straw for the body, and a paper tail.
Most modern hang gliders are made of an aluminum alloy or composite frame covered with synthetic sailcloth.

Imagine a next generation Windsports Hang Glider Factory and training center.

[JoeF]

Chordwise straight three-tube compression strut using two instances of Joe Coupler (also known as Joe Cup)
and two instances of T-and-strap coupling:
Assume for this note: TPHG as a SS HG.
In tote have the three tubes that make up each chordwise strut be telescopic to each other.
In assembly let the subject strut be a spreader between fore and aft meta spars.
In assembly let the subject strut be a base for at least one vertical small strut that holds up a camber-forming batten.
In assembly let the subject strut carry a spanwise line that will base some further vertical small struts that will also support camber-forming battens.
In tote have the Joe Cups and T-and-Strap couplets be fully separated from their tubes.
The straps of the T-and-Straps will hold the subject three-tube-struts to the meta spars.
The sail covering of the TPHG frame will be non-taut until the vertical small struts press the camber-forming battens and the base of the small vertical strut is seated onto the three-tube spar-spreading strut.

Chordwise Three-Tube Compression Strut with Joe Coupler and T-and-Strap Coupling for TPHG (Tiny Pack Hang Glider)

This design note describes the chordwise strut assembly for a Tiny Pack Hang Glider (TPHG), specifically a Single-Surface (SS) glider. The chordwise strut functions as a compression element between the fore and aft meta spars, while supporting camber-forming components that help shape the glider's wing for flight.

Key Components and Features:
==Telescopic Three-Tube Chordwise Strut:
==Packed state (Tote): The chordwise strut is composed of three nested, telescoping tubes for compact storage.
==Assembled state: When assembled, the tubes are extended to form a straight compression strut that spans the distance between the fore and aft meta spars, helping to stabilize the frame.
==Joe Coupler (Joe Cup) and T-and-Strap Coupling:
====Joe Couplers: Two Joe Cups are used to connect and secure the telescopic tubes when extended, ensuring rigidity in the structure.
====T-and-Strap Coupling: Two T-and-Strap fittings attach the strut to the fore and aft meta spars. Straps are used to secure the strut in place, while allowing easy detachment during disassembly.
Tote storage: When the glider is packed, both the Joe Cups and T-and-Strap fittings are fully separated from the tubes for efficient packing.

Camber-Forming Batten Support:
In assembly, the chordwise strut will act as a base for small vertical struts, which support camber-forming battens. These battens will help shape the camber (curvature) of the single-surface wing.
A spanwise line, anchored to the chordwise strut, will allow the installation of additional small vertical struts along the span, each supporting battens to help shape the desired wing curvature.

Sail Interaction:
The single-surface sail will remain non-taut during initial assembly.
When the small vertical struts are positioned and press the camber-forming battens upward, the sail will tighten to form the desired airfoil shape.
The base of each small vertical strut will seat onto the chordwise strut, completing the camber-forming setup and ensuring proper sail tension.

Summary: This design enables a compact, easily transported glider, with key structural components (the telescopic tubes, Joe Cups, and T-and-Strap couplings) separating for a small packing footprint. The use of vertical struts and battens allows for precise control of wing camber during assembly, ensuring efficient flight performance while maintaining the simplicity of a single-surface design.

[JoeF]

This paper's strut may or may not affect some TPHG (tiny-packable hang glider):
Self-Deploying Tensegrity Structures with Inflatable Struts
Jonathan Dessi-Olive

2019, Proceedings of the 60th International Association of Shell and Space Structures Symposium

This paper presents research on a hybrid structure system that extends the principles of active-deployed tensegrity structures through a series of prototypes that use inflatable compression struts. These structures combine the advantages of tensegrity and pneumatic structures, resulting in minimum weight with a maximal global volume change. Previous deployable tensegrity structures have been developed that demonstrate self-deploying behavior, but only at small scale. Prototypes that use commonly known three and four-strut geometries were built that use low-pressure inflatable struts, developed to maintain their internal air pressure, resist strut deformation that can occur during deployment, and resist buckling that results from loading the structure. The prototypes presented here precede a large-scale pavilion to be exhibited at the 2019 Form and Force Expo in Barcelona. This paper presents several development prototypes, design and analytical strategies for the inflatable compression struts, load-testing results, as well as drawings of the proposed exhibition structure.

=================================
Other radiance from Jonathan Dessi-Olive might impact TPHG development: See one of his radiant pages HERE.
And his page and image on "Air-Ten Module"
===================

Jonathan, we are keeping you and yourworks in mind as we make progress on hang gliders that may back away in super low volume manner. I posted some links about you in US Hawks forum.
https://ushawks.org/forum/viewtopic.php ... 332#p35332
Thank you for your good works,
Best to you and yours,
Joe Faust

===================

[JoeF]

This is a sharing of a flash passing my mind a minute ago.
Topic: TPHG wing covering method of sail segments only overlaid, not stitched, nor zippered.
In a glider with fore and aft spars, some exploration of this method might reveal some assets and liabilities. I will be trying out segment overlay and reporting results.
A quick feed to ChatGPT with brief prompt gave some ideas that are a bit off topic, maybe bad, but maybe some inspiration. I put its response below:

TPHG Wing Covering Option: Overlay Method

Covering a TPHG (Tiny Packed Hang Glider) wing using an overlay method without stitching or zippers is an innovative approach that could simplify construction, reduce weight, and enhance aerodynamic performance. Here’s a detailed exploration of this concept:

Concept Overview
- Overlay Method: This involves placing fabric segments over each other in a manner that they lie flat against the structure of the wing, forming a continuous surface without mechanical fasteners.
- Material Choice: Lightweight, durable materials such as ripstop nylon or polyester, perhaps with a silicone or polyurethane coating for water resistance, could be suitable. These materials are commonly used in parachutes and ultralight sails.
- Benefits of Overlaying:
- Weight Reduction: Eliminating stitching and zippers can reduce the overall weight of the sail, which is crucial for glider performance.
- Simplified Assembly: Overlaying could streamline the covering process, making it easier to install and remove for maintenance or repairs.
- Aerodynamic Smoothness: A continuous surface can enhance airflow over the wing, improving lift and reducing drag.

Design Considerations
1. Segmentation:
- Divide the wing into several segments that can be easily overlaid. Each segment should cover a portion of the wing and could be designed to interlock slightly to prevent gaps.
- Consider the shape and contours of the wing to ensure that segments fit snugly without creating bulges or wrinkles.

2. Attachment Method:
- Use adhesives or hook-and-loop fasteners (like Velcro) along the edges of the fabric segments to keep them in place.
- Alternatively, use a tensioning system where the fabric is pulled tight against the wing frame using straps or elastic cords.

3. Edge Finishing:
- Edges of the segments can be treated with a heat-sealing method to prevent fraying and to create a more streamlined appearance.
- Ensure that the edges of the fabric are smooth to avoid any interference with airflow.

4. Testing and Adjustments:
- Conduct wind tunnel tests or flight tests to observe the aerodynamic properties of the overlay method. Adjust the fabric tension and segment overlap as needed to optimize performance.

5. Weather Resistance:
- Ensure that the chosen materials are resistant to UV degradation and water. Consider additional coatings for durability.

6. Ease of Maintenance:
- Design the system so that segments can be easily removed for cleaning or replacement without damaging the overall structure of the glider.

Potential Challenges
- Durability: The long-term durability of the overlay method may need to be tested, especially in varying weather conditions.
- Fabric Stretch: Choose materials with minimal stretch to maintain shape and performance over time.
- Wind Load: Ensure that the attachment method can handle the aerodynamic loads without failure.

Conclusion
This overlay method for TPHG wing covering presents an exciting avenue for innovation in glider design. By focusing on weight reduction, ease of assembly, and aerodynamic efficiency, it could enhance overall performance while simplifying the construction and maintenance processes. Careful consideration of materials and design techniques will be essential to ensure success.

Would you like to delve deeper into any specific aspects of this covering method?

My first retort concerns the air leaks at the sail-segment overlays. My flash did not want to Velcro or zipper or seam connect; the flash was concerning simple overlay, maybe chordline 3 inches wide of overlay; how much wing-loaded air leaking will spoil the fun? Sacrificial duct tape is not fun, either.

Here is ChatGPT's response to my first retort:

Addressing Air Leaks in TPHG Wing Covering

My first retort concerns the air leaks at the sail-segment overlays. A simple overlay method without Velcro, zippers, or seams raises important issues. Here’s a breakdown of how to manage these potential air leakage problems:

Air Leaks and Their Impact
1. Nature of Air Leaks:
- Overlay Method: With a simple overlay, air can flow between segments if not properly managed, potentially leading to turbulence and reduced lift. Even a small gap can result in significant air leaks, especially under load.
- Chordwise Overlap: A 3-inch chordwise overlap could help mitigate some leakage, but the effectiveness will depend on how well the segments are aligned and secured.

2. Wing Loading Considerations:
- Impact on Performance: Excessive air leaking can spoil the gliding experience by reducing lift and increasing drag. For a hang glider, maintaining airflow over the wing surface is essential for achieving optimal lift-to-drag ratios.
- Critical Threshold: The degree to which air leaks affect performance will depend on the overall wing design and conditions (e.g., speed, angle of attack). A well-designed wing might tolerate minor leaks, while a heavily loaded wing may require tighter seals.

Solutions to Minimize Air Leakage
1. Precision Overlap:
- Aim for a snug fit between overlay segments. Use slight tensioning to keep segments flat and in contact without any gaps.
- Testing for Fit: Before finalizing the design, prototype and test different overlaps to see which provides the best balance between ease of assembly and performance.

2. Temporary Adhesives:
- Consider using lightweight temporary adhesives or tape that can provide a tighter seal without adding significant weight.
- Double-Sided Tape: Using a double-sided tape designed for fabric could provide an easy way to secure the overlaps without the permanence of stitching.

3. Surface Treatments:
- Treat the edges of each fabric segment to prevent fraying and help them lie flat against each other. This can enhance airflow continuity.
- A thin layer of silicone or similar material along the edges can help create a better seal without adding bulk.

4. Design Adjustments:
- Explore the possibility of slight contoured cuts along the edges of segments to create a more interlocking fit, reducing the likelihood of air gaps.
- Using scalloped edges or similar shapes can help segments interlock better and minimize leakage.

5. Testing and Iteration:
- Conduct wind tunnel tests or real-world flight tests to evaluate how the overlay design performs in terms of air leaks and overall efficiency.
- Be open to iterative adjustments based on test results. Minor tweaks can lead to significant performance improvements.

Conclusion
While simple overlays present challenges regarding air leakage, careful design considerations and material choices can minimize their impact. The goal is to maintain a balance between simplicity and performance while ensuring that the gliding experience remains enjoyable. Prototyping and testing various solutions will be key to finding the optimal approach for your TPHG wing covering. If you have any specific preferences for materials or techniques, let’s dive into those!

Wanting to avoid bulk at the overlay edges of the sail segment (Velcro, zippers, tape, etc., add bulk and artful works) and wanting not to waste (sacrificial tapes) and wanting to stay simple for easy disassembly for packing compactly between flight days, I seek some means to stop the air leaks between the overlays that are chordwise for the meta wing covering. Super thin hook texture against super thin loop structure might be available, but might not be. Magnetic treatment might or might not be bulking. One does not want the overlay area to pop open during flight! A series of tiny snaps still adds work and bulk. Reminder: This exploratory post probably has a good deal of poor ideas and even errors, but I did not want to miss the chance to adventure into the subject realm scratchingly.

Potential Solutions for Overlay Air Sealing

Your concerns about bulk at the edges of the sail segments and the need for a simple, effective solution to minimize air leaks are valid and worth exploring. Here are several ideas to help address these challenges while keeping the design streamlined and efficient:

1. Adhesive Film:
- Ultra-thin Adhesive Film: Consider using a very thin, pressure-sensitive adhesive film that can adhere the edges of the overlay without adding bulk. This film could create a semi-permanent bond that can be removed for disassembly.
- Benefits: Maintains a clean edge without added weight and allows for easy reapplication if needed.

2. Super Thin Hook-and-Loop (Velcro):
- Minimalist Approach: If a hook-and-loop solution is viable, opt for the thinnest available options, specifically designed for lightweight applications. These can provide enough surface area to keep the overlays sealed while minimizing bulk.
- Positioning: Strategically place them along the edges of the segments, focusing only on areas where airflow is most critical.

3. Magnetic Sealing:
- Magnetic Strips: Thin magnetic strips can be incorporated along the edges of the overlays. This method can create a strong closure while being lightweight and easy to assemble/disassemble.
- Weight Consideration: Ensure that the magnets used are thin and lightweight to avoid adding unnecessary bulk.

4. Tensioning System:
- Dynamic Tensioning: Use a system where the edges of the sail segments are tensioned together using lightweight elastic cords or bungee systems. The tension would pull the overlay segments snug against each other.
- Ease of Assembly: This system allows for quick disassembly and reassembly without sacrificing the airtight seal during flight.

5. Micro-Snap Fasteners:
- Tiny Snaps: While you mentioned that snaps add bulk, consider using ultra-small snap fasteners strategically placed only where necessary. This could provide a secure closure without significant weight.
- Placement: Limit their use to high-stress areas to minimize overall bulk.

6. Fabric Treatments:
- Sealant Spray: Use a lightweight fabric sealant spray that creates a flexible, air-tight seal along the edges of the overlays. This method avoids mechanical attachments and adds minimal weight.
- Temporary Nature: Make sure the sealant allows for removal if necessary, or explore options that provide a temporary bond.

7. Seamless Edge Design:
- Contoured Edges: Design the overlay edges with a contoured shape that allows for a better fit when overlapping. The contour can help minimize gaps while maintaining a sleek profile.
- Scalloped Edges: Scalloped or wave-shaped edges can help with interlocking without the need for additional fasteners.

Conclusion
The goal is to achieve a balance between sealing the overlays to minimize air leaks and maintaining a lightweight, bulk-free design. Each of these solutions can be adapted and combined to suit your specific needs, allowing for easy disassembly and compact packing. Testing prototypes with various materials and configurations will be essential in finding the right combination that meets your performance and usability requirements.

If you have any specific preferences or need further exploration into any of these ideas, let me know!

Maybe along a 6 ft line of overlay, about five temporary tiny poke-through removable rivets could play a role of keeping the overlay of 3 inches from becoming anything less than 3 inches.

Poke-Through Removable Rivets for Overlay Maintenance

Integrating tiny poke-through removable rivets along the overlay is an interesting idea to maintain the integrity of the 3-inch overlap while minimizing bulk and complexity. Here’s an exploration of how this concept could work, along with some benefits and considerations:

1. Design Concept:
- Placement: Consider placing about five tiny rivets evenly spaced along the 6-foot line of the overlay. These would be designed to secure the overlay in place without causing excessive bulk or damage to the fabric.
- Removable Feature: The rivets should be designed for easy removal, allowing for quick disassembly when packing the glider.

2. Material Selection:
- Lightweight Materials: Use lightweight materials for the rivets, such as plastic or aluminum, to minimize additional weight.
- Non-Damaging Design: Ensure that the rivets have smooth edges and a design that doesn’t damage the fabric or create significant stress points.

3. Installation Method:
- Poke-Through Mechanism: The rivets can be installed by simply poking them through the overlapping edges of the sail segments. Consider a design where the rivets can easily slide in and out without requiring tools.
- Clamping Mechanism: A clamping mechanism at the top of each rivet can keep the overlay secure without damaging the fabric.

4. Benefits:
- Maintains Overlay Width: The rivets will ensure that the overlay remains consistently 3 inches wide, preventing any buckling or shifting during flight.
- Lightweight Solution: Since the rivets are removable and made of lightweight materials, they won’t significantly add to the overall weight of the glider.
- Ease of Disassembly: Quick removal of the rivets allows for easy packing and transport between flights.

5. Considerations:
- Air Leakage: While rivets can help maintain the overlay, they may create small holes that could lead to air leakage. Ensure that the holes are minimal and positioned in a way that doesn’t affect overall performance.
- Testing Required: It’s essential to test the rivet placement and design in real-world conditions to evaluate their effectiveness in maintaining the overlay and ensuring airworthiness.

Conclusion
Using poke-through removable rivets could be a practical solution to maintain the integrity of the overlay in your TPHG design while keeping things simple for disassembly and packing. It offers a lightweight, effective means to ensure that the overlay remains secure without significant bulk.

If you want to explore specific designs or materials for the rivets further, feel free to ask!

Maybe another option: Have the edge of each sail segment feature a 1" wide starched edging that during assembly of the glider, folds over to make a long hook-like scene; the two edges then "hook" along the full edge; then the tension of flight might keep the hooks hooked; or a few poke-through rivets might help the hinged hooking persist during flight loading

Starched Edging Hook Mechanism for Sail Segments

Another interesting option to consider is featuring a 1-inch wide starched edging on the edge of each sail segment. Here’s how this concept could work:

1. Design Concept:
- Starched Edging: Each sail segment would have a 1-inch wide starched edging. This edging could provide some stiffness and structure to the overlay.
- Folding Mechanism: During the assembly of the glider, this starched edging would fold over, creating a hook-like shape along the full edge of the sail segment.

2. Hooking Mechanism:
- Interlocking Edges: The folded edges of the sail segments would "hook" together, creating a secure connection that could prevent air leaks.
- Tension during Flight: The tension generated during flight might help keep the hooks securely interlocked, maintaining the integrity of the overlay.

3. Additional Support:
- Poke-Through Rivets: To enhance the security of the hooked edges during flight loading, consider adding a few poke-through rivets along the edges. These would help ensure that the hooks remain engaged and prevent any separation under load.

4. Benefits:
- Lightweight Solution: This design approach keeps the connection lightweight, avoiding the bulk associated with traditional fastening methods.
- Ease of Assembly: The hooking mechanism allows for quick and easy assembly and disassembly of the sail segments.

5. Considerations:
- Durability of Starch: Ensure that the starch used for the edging can withstand the environmental conditions without losing its effectiveness.
- Testing Required: It’s essential to test the effectiveness of this mechanism in real-world conditions to assess its performance and reliability during flight.

Conclusion
Utilizing a starched edging hook mechanism for the sail segments can offer a lightweight and effective way to maintain the integrity of the overlay. The combination of tension during flight and optional poke-through rivets may provide a secure solution for your TPHG design.

If you have any further questions or would like to explore this concept more, feel free to ask!

Zippering seems again attractive after discussing these zipper-less optional adventures! If only zippers did not bulk when rolled on a core for compact tote time!

Reconsidering Zipper Options for TPHG Wing Covering

After exploring various zipper-less options for the wing covering, the concept of using zippers is once again becoming attractive. Here’s a look at the potential benefits and drawbacks:

1. Benefits of Zippers:
- Secure Closure: Zippers provide a reliable way to keep the sail segments securely closed, minimizing air leaks during flight.
- Ease of Assembly and Disassembly: Zippers allow for quick and efficient assembly and disassembly of the glider, making it easy to pack and transport.
- Tension Maintenance: When zipped, the tension in the fabric can help maintain the integrity of the wing shape during flight.

2. Drawbacks of Zippers:
- Bulkiness: One of the main concerns is that zippers can add bulk, especially when rolled around a core for compact storage. This could impact the overall packing dimensions of the TPHG.
- Weight Considerations: Depending on the materials used for the zippers, there could be added weight, which is a critical factor in glider design.

3. Potential Solutions:
- Slimmer Zipper Designs: Consider exploring zippers designed specifically for lightweight applications. Some zippers are made with thinner materials that could reduce bulk.
- Alternative Zipper Styles: Look into options like coil zippers, which may offer a more flexible solution that could roll up more compactly than traditional zippers.
- Placement Strategy: Strategically placing zippers only where necessary could help limit bulk while still providing the benefits of a secure closure.

4. Conclusion
While the exploration of zipper-less options has been valuable, zippers still present an attractive solution for maintaining the integrity and functionality of the wing covering. Balancing the benefits of zippers against their potential bulk and weight will be crucial in making a final decision for the TPHG design.

If you have any further thoughts or want to discuss this option more, feel free to share!

And maybe not segmenting the sail might remain best! During tote, avoiding packing bulking from seams is a tall challenge.

Considering a Continuous Sail for TPHG Design

After evaluating the various options for segmenting the sail and their implications, it may be worth considering the benefits of keeping the sail as a continuous piece. Here are some thoughts on this approach:

1. Benefits of a Continuous Sail:
- Reduced Bulk: One of the primary advantages is the significant reduction in bulk during packing. Avoiding seams and segmentation means there are fewer components to stack, which can lead to a more compact and efficient tote.
- Improved Aerodynamics: A continuous sail could provide a smoother airflow over the wing surface, potentially enhancing aerodynamic performance and reducing drag.
- Simplified Assembly: Without the need to connect multiple segments, the assembly process could be streamlined, making it easier and faster to set up the glider before flight.

2. Challenges to Consider:
- Storage Size: While a continuous sail minimizes bulk, it may impact the size of the packed glider. Consider how the overall length and width will fit into your storage solution.
- Handling and Flexibility: The handling of a larger, continuous sail during assembly and disassembly might require additional care to avoid tangling or damaging the fabric.

3. Potential Solutions:
- Folding Techniques: Investigate folding techniques that could minimize the sail's overall size without compromising its integrity. Techniques such as rolling or specific accordion-style folds may help.
- Material Choices: Consider lightweight, flexible materials that maintain durability while allowing for easier handling during packing and unpacking.

4. Conclusion
Ultimately, maintaining a continuous sail could be the best option for the TPHG design, focusing on minimizing packing bulk and simplifying the assembly process. The aerodynamic advantages and reduced complexity make this a compelling approach.

If you have additional thoughts on this concept or other ideas to explore, please share!

ChatGPT, you assumed "continuous sail" would not have bulking sewn segment seams; that kind of sail could be prohibitively expensive. Consider left wing sail and right wing sail. Pack two items of sail. If there were not compound surfaces, but true flats, then packing volume could be smaller. Core rolling for tote of the sails might be able to be kept to a low pack volume.

Exploring Flat Sails for Left and Right Wings in TPHG Design

In light of recent discussions regarding sail segmentation and packing efficiency, it’s worth considering the concept of using flat sails for the left and right wings. Here are some thoughts on this approach:

1. Benefits of Flat Sails:
- Reduced Bulk: By utilizing flat sail designs rather than compound surfaces, the overall bulk can be significantly reduced. This could make packing more efficient and allow for a more streamlined tote.
- Two Separate Sails: Having a left wing sail and a right wing sail as individual components simplifies the assembly process while still allowing for effective wing performance. This separation could also make repairs or modifications easier.

2. Core Rolling for Packing:
- Compact Storage: Flat sails can be rolled around a core more efficiently than segmented sails. This method allows for a lower packing volume, which is ideal for transporting the TPHG between flights.
- Material Choices: Selecting lightweight and flexible materials for the flat sails can further enhance the ability to roll them compactly without compromising durability.

3. Considerations for Implementation:
- Connection Mechanism: While the sails are separate, a reliable connection mechanism will still be necessary for attaching the sails to the wing structure securely. This could involve hook-and-loop fasteners, lightweight clips, or other fastening methods that do not add significant bulk.
- Handling and Storage: Ensuring that the sails can be easily handled and stored without creasing or damaging the material is crucial for maintaining their performance.

4. Conclusion
Opting for flat sails for the left and right wings could provide an effective solution for minimizing packing volume while maintaining the integrity and performance of the TPHG. The ability to core roll the sails can facilitate easier transportation and enhance overall usability.

If you have any further insights or ideas on this concept, please feel free to share!

Perhaps string tie a button through super-flat eyelets to halt ballooning out of overlapped fabric?

Using Button and String Tie Mechanism to Prevent Ballooning in Overlapped Fabric

Considering the challenges of managing air leaks and ballooning in overlapped fabric, a potential solution involves the use of button and string tie mechanisms through super-flat eyelets. Here are some thoughts on this approach:

1. Concept Overview:
- By incorporating super-flat eyelets into the edges of the sail segments, you can create anchor points for string ties. This would allow for a secure method of holding the overlapping fabric in place during flight.

2. Benefits of This Approach:
- Prevention of Ballooning: Tying strings through the eyelets can help maintain tension across the overlaps, preventing the fabric from ballooning outwards and minimizing air leaks.
- Lightweight and Simple: This method avoids the bulkiness associated with zippers, Velcro, or other fastening systems, keeping the design lightweight and streamlined.
- Ease of Assembly and Disassembly: The button and string tie method offers a straightforward way to secure the fabric during assembly while allowing for easy disassembly for compact packing.

3. Implementation Considerations:
- Material Selection: Choose lightweight, durable string and buttons that won’t add significant weight or bulk to the overall design.
- Eyelet Placement: Strategically place the eyelets along the edges of the overlapped fabric to ensure effective tensioning without creating stress points that could lead to fabric damage.

4. Conclusion
Utilizing a button and string tie mechanism through super-flat eyelets could provide an effective solution for managing overlapped fabric in the TPHG design. This method emphasizes simplicity and functionality while minimizing bulk and ensuring aerodynamic performance.

If you have any thoughts on this concept or additional ideas to explore, feel free to share!

[JoeF]

A chat about some possible options:

User: In my tiny-packed hang glider, there are many segment CF tubes that are 4 ft long. I want a few parts to convert one of those tubes into being an air pump. I would pump up two 15-ft long air beams of 12 inches inflated diameter at one end tapering to 6 inches diameter at the wing tip. The two bladders will have a connecting umbilical to assure both left and right inflated beams have the same air pressure during flight. The two connected air beams are for aero-curving the sail of the wing, not for spar structure. How to convert one of the frame tubes into an air pump?

ChatGPT: To convert one of your 4-foot long carbon fiber (CF) tubes into an air pump for inflating your 15-foot air beams, you can follow these steps to design a simple and lightweight hand pump:

1. Piston Design
- Piston Rod: Use a lightweight rod, such as a fiberglass or carbon fiber rod, that runs inside the 4-foot CF tube. This rod will move back and forth to generate pressure.
- Piston Head: At the end of the rod, attach a circular piston head that seals against the inner walls of the CF tube. Use a flexible material like rubber or silicone to create a tight seal. Consider adding O-rings to enhance the seal.
- Handle: Attach a lightweight handle to the rod outside the tube to allow manual operation of the piston.

2. One-Way Valves
- Inlet Valve: Install a one-way valve at the bottom of the CF tube to let air in as the piston is pulled up. You can use an off-the-shelf check valve or design a simple flap valve using silicone or rubber.
- Outlet Valve: Place a second one-way valve at the top of the tube to release air into the air beams as the piston is pushed down.

3. Air Connections
- Hose Connection: Add a connector at the outlet valve to attach an air hose that leads to the two air beams. You can use a quick-connect fitting to make assembly and disassembly easier.
- Umbilical Link: Ensure the hose system includes a Y-connector or a T-fitting to split air equally between the two beams. The umbilical between the beams should allow for equalization of pressure.

4. Pump Functionality
- Dual-Action Design (Optional): For greater efficiency, consider a dual-action pump design where air is pushed into the beams both when the piston is pulled up and when it is pushed down. This would require both ends of the CF tube to have one-way valves (inlet at the bottom and outlet at the top), with the piston head sealed in the middle.

5. Storage and Transport
- Modularity: Since the CF tube is part of the glider's structure, the piston assembly (rod, piston head, handle) should be removable. Design the handle and rod to detach from the tube so the tube can be used as part of the glider frame during flight. A screw-in or clip-in system would allow quick conversion between pump and frame modes.

6. Inflation System
- Pressure Management: Use a pressure gauge at the outlet valve or as part of the umbilical system to monitor the air pressure in the beams. You can incorporate a simple inline gauge.

Summary of Key Parts:
- Piston rod (lightweight carbon fiber or fiberglass)
- Piston head (flexible material like rubber or silicone with O-rings)
- Handle for pumping
- One-way inlet and outlet valves
- Quick-connect fittings for air hoses
- Y-connector or T-fitting for air distribution between the beams
- Optional pressure gauge for monitoring inflation.

This setup will convert one of your CF tubes into a compact and efficient hand pump for inflating your air beams, allowing easy assembly and transport with your hang glider design.

User: An alternative is a solar-powered tiny air pump. Just start inflating as soon as I arrive at the flying site; the tiny pump will inflate the air beams by the time I get the TPHG assembled!

ChatGPT: A solar-powered tiny air pump is a fantastic alternative to a manual pump for inflating your air beams while you focus on assembling the Tiny Packed Hang Glider (TPHG). Here’s how you can design and implement a small, efficient solar-powered air pump system:

1. Selecting the Air Pump
- Compact DC Air Pump: Choose a small, lightweight DC air pump that operates at low voltage (e.g., 6V or 12V). Many pumps designed for inflatable kayaks or air mattresses are portable and can easily be adapted. Ensure the pump can provide sufficient pressure for the 12-inch to 6-inch tapered beams.
- Flow Rate: Select a pump with an airflow rate that matches your inflation needs. Since the system can work slowly while you assemble the glider, you don’t need a high-powered pump, but it should be able to handle the volume of air required for the two 15-foot beams.

2. Solar Power System
- Solar Panel: A small foldable or flexible solar panel (10-20W) would be sufficient to power the tiny pump. The panel should be lightweight and easily packable with the glider.
- Flexible Solar Panel Options: Look for ultralight or flexible panels, often used for camping or backpacking. These can be draped over your setup or laid on the ground while inflating.
- Solar Charge Controller (Optional): If you’re using a battery to store the solar energy, a small charge controller ensures the battery doesn’t overcharge and efficiently regulates power to the pump.

3. Battery Backup (Optional)
- Battery Pack: A small rechargeable lithium battery pack (such as those used in power banks) can store solar energy and run the pump. You can charge the battery during the day and use it for inflation even on cloudy days or at dusk.
- Battery Specs: A 12V 2000mAh lithium battery pack should be enough to run a small DC air pump for a reasonable duration.

4. Air Connection to Beams
- Y-Connector and Umbilical: Use a Y or T-fitting to split the air evenly between the two beams. Ensure that the air pump hose can connect securely to the beams and maintain a consistent pressure as they inflate.
- Pressure Monitoring: Add a simple inline pressure gauge or automatic shut-off valve when the beams reach their ideal pressure to avoid over-inflation.

5. Design Considerations for the Glider
- Lightweight and Compact: Keep the pump and solar panel small and lightweight to maintain the portability and efficiency of your TPHG. Both components should be easily storable with the rest of your glider.
- Inflation Time: Depending on the pump’s output, the inflation time may vary, but given that the pump will run while you set up the rest of the glider, this won’t interfere with your workflow.

Example Setup:
- Solar Panel: 20W flexible panel (size: about 12 x 9 inches, weight: around 0.7 lbs)
- Air Pump: 12V DC air pump with 300-500 L/min flow rate (weight: about 0.5 lbs)   [[sic: Chat later recanted and saw that the suggested flow rate was overblown! Less rate would suffice.]]  
- Battery Backup (Optional): 12V 2000mAh battery pack (weight: around 0.3 lbs)
- Air Hose: Lightweight silicone or rubber tubing with quick connectors
- Y-Connector: To evenly distribute air to both beams
- Pressure Gauge or Shut-Off: Monitor air pressure during inflation

Benefits of the Solar-Powered Approach:
- Hands-Free Inflation: You can focus on assembling your hang glider while the solar-powered pump does the inflation work.
- Renewable Energy: Solar power eliminates the need for manual effort or carrying additional fuel or batteries (except a small backup battery, if desired).
- Consistent Pressure: A slow, steady inflation ensures the air beams maintain equal pressure for proper wing shape.

With this solar-powered system, your air beams can be inflated and ready by the time you're finished assembling the glider, making the process more efficient and saving your energy for the flight!

[JoeF]

Efficient Packing for Hang Glider Sail Segments with Side Zippers

A key challenge in packing a tiny hang glider with sail segments that feature side-running zippers is managing the bulk of the zippers to achieve a compact, wrinkle-free roll. Here's an effective solution:

When wrapping the sail around the toted core frame, ensure that the zipper tape runs beyond the edges of the core at both ends. By positioning the zipper's bulk outside the core's boundary, the sail can roll smoothly around the frame without the zipper adding bulk or creating wrinkles along the core's surface. This method keeps the zipper free from compressing against the sail fabric, allowing for a cleaner wrap and a much lower pack volume.

This approach ensures that the sail wraps tightly and efficiently around the frame while keeping the zipper edges suspended in free space beyond the core's edges. The result? Minimal wrinkles and a more compact, travel-friendly pack.

For example, if the packed frame forms a core of three tubes (telescopic nested frame tubes inside those three tubes) and the width is 48 inches, then aim to have sail segment runs be 50 inches permitting 1 inch overhang where the zipper halves bulk at the edges of the roll. The main body of the sail segments then may be snugly smoothly wrapped on the frame core.

SewZippersOntoSegmentsThatAreWiderThanCore.jpg (32.46 KiB) Viewed 757 times

[dhmartens]

Sorry to go off topic but we have the 5 foot hang glider fully developed with the office of Naval Management and it is classified. We are ready to use it because of the state of Missouri desecration of Robert Creutz a disabled US vereran in probate court who was born in the Philippines and was the son of William Creutz a US citizen and aviator. Flown robotically or with a hospice patient who would never stand trial we wil take down another B2 bomber at Fort Leonard Wood with a gatlin crossbow gun or other method. My AI says Missouri exterminated Mormons using executive order 44.

The Missouri extermination order stood for 138 years and has been interpreted by many as a license to kill Mormons, even though since 1838 Mormons have lived in Missouri without conflict. In 1976 then-Governor Kit Bond rescinded the extermination order.
https://johnmjennings.com/could-mormons ... 138-years/



One way or another the state of Missouri will burn.
Bob I wish we were not in so much pain in these difficult times with the death and desecration of a loved one. But I wil post videos of the new telescopic hang glider once we have healed the pain of our loss.

[JoeF]

https://www.dyneema.com/sectors/sports- ... erd-spokes
Will Berd spokes play a role or two in some TPHGs? , maybe in rigging or tote or both?

Not seen, but wondering: structural tubing composite based on Dyneema? Go or no go?

Dyneema rigging lines: https://www.dyneema.com/sectors/sports- ... ding-lines