Kit Double roller muzzle and Handle for Ermes Sub Future, for tubes with ID 26mm, 3D printed.

MUZZLE
The muzzle has been designed to be as simple and lightweight as possible. Its compact size does not affect the weapon's maneuverability.

The muzzle is designed with line wrap slots on both sides for convenience.

The stopper is integrated into the piece, while the side plates are removable.
The pulleys come in 2 different sizes and are included in the files for 3D printing. The bands align perfectly without overlaps or friction.

The t is equipped with 2 slots for O-rings to make the tube watertight, while the stopper slot is isolated by a cylindrical chamber to prevent flooding.

HANDLE

The handle has been designed to mount the Ermes Sub FUTURE release system (it is also compatible with the roller models of the FUTURE series). The choice of the FUTURE system is due to its reliability, compactness, and lightness. The presented model has been developed to be fast and maneuverable, particularly suited for quick and instinctive shots.

The ergonomic handle has been designed to be comfortable and anatomically shaped, ensuring a secure grip. The handle size is medium, adaptable to all hand sizes, even when wearing 5mm thick gloves.

The handle also allows the Ermes FUTURE line release to be switched from one side to the other.

The inside of the handle is hollow, allowing for the insertion of foam in case of heavy setups or a negatively buoyant speargun, making it positively buoyant. The handle block includes hollow chambers to reduce weight.

The hilt is equipped with a base for attaching vertical reels, reducing bulk and improving maneuverability by shifting the reel backward.

The muzzle and handle are compatible with tubes with an inner diameter (ID) of 26 mm and an outer diameter (OD) ranging from 28 mm to 31 mm, making them compatible with all commercially available tubes, whether made of carbon or aluminum.

IMPORTANT NOTE

Print with no thickness, directly as solid material (i.e., 100% INFILL), to avoid breakage or accidental damage to people or property.

Use solid materials such as ASA, PA6-CF, PA6-GF30, PA12-CF, and PEEK.

WARNING:

The project is intended for private use only and can be used for recreational purposes as often as desired. Commercial reproduction is strictly prohibited; the project is ed and protected by copyright.

Closed-chamber printing is recommended. Use solid materials such as ASA, PA6-CF, PA6-GF30, PA12-CF, and PEEK.

In addition to the .stl files, .step files are also included. Those who are more experienced or fortunate can machine the full piece in Delrin using a CNC with a rotary fourth axis or 5-axis.

Among the files, you will find both the version of the muzzle with internal air chambers and the solid (full) version. The choice between the two models depends on the specific weight of the filament used.

Materials and/or specifications for machining from solid with CNC.

Nylon

• Nylon 6 (PA6) - 1.13 g/cm³
  
• Nylon 6 CF (PA6-CF) carbon fiber reinforced: ~1.2-1.3 g/cm³
  
• Nylon 6 GF15 (PA6-GF15) 15% glass fiber reinforced: ~1.21-1.27 g/cm³
  
• Nylon 6 GF30 (PA6-GF30) 30% glass fiber reinforced: ~1.35-1.45 g/cm³
  
• Nylon 12 (PA12) - 1.01 g/cm³
  
• Nylon 12-CF (PA12-CF) carbon fiber reinforced: ~1.0-1.1 g/cm³
  
• Nylon 46 (PA46) - 1.20 g/cm³
  
• Nylon 66 (PA66) - 1.14 g/cm³
  

Among the nylons, Nylon 12 (PA12) has very low moisture absorption (about 0.25-0.3%), ensuring greater dimensional stability even in humid or submerged environments compared to other variants like Nylon 6 and Nylon 66. Additionally, the specific weight of Nylon 12 is lighter than seawater, at only 1.010 g/cm³, while seawater has a specific weight ranging between 1.020 and 1.030 g/cm³.

Delrin (POM - Polyoxymethylene)

• Delrin 150 - 1.41 g/cm³
  
• Delrin 100 - 1.41 g/cm³ (stiffer than Delrin 150)
  
• Delrin 527UV - 1.41 g/cm³
  
• Delrin 570 - 1.42 g/cm³ (glass fiber reinforced, structurally stronger)

Teflon (PTFE)

• Teflon G - 1.50 g/cm³ "variable" (15-25% glass fiber reinforced)
  
• Teflon GF - 1.60 g/cm³ "variable" (20-30% glass fiber and graphite reinforced)
  
• Teflon C - 1.55 g/cm³ "variable" (25-26% carbon reinforced)

Other materials

• ASA (Acrylonitrile Styrene Acrylate): ~1.07 g/cm³
  
• PEEK (Polyether Ether Ketone): ~1.3-1.32 g/cm³
• Polypropylene (PP) Density: 0.89 - 0.91 g/cm³ (one of the lightest polymers)
  

Polypropylene (PP) is an excellent choice when lightness and buoyancy are required. It offers a good balance between strength, low weight, and cost-effectiveness. It is commonly used for lightweight, impact-resistant, and chemically inert components, such as containers, automotive parts, and medical devices.

To improve printing quality, it is recommended to use enclosed chambers and specific adhesion surfaces.

It is very lightweight, with a density range of 0.89 - 0.91 g/cm³. It has moderate elasticity and good tensile strength.

Chemical and Physical Properties

- Water absorption: Almost zero (less than 0.03%)

- Wear resistance: Good, ideal for mechanical parts subjected to stress

Common Issues in 3D Printing

- Bed adhesion: Difficult, often requires a PP bed or specific adhesives

- Warping: High, tends to shrink during cooling

- Flexibility: High, making it challenging to print fine details
Esistono diverse varianti di polipropilene, tra cui quelle caricate a fibre, che sono progettate per migliorare determinate proprietà meccaniche del materiale. I polipropileni caricati a fibre offrono una maggiore rigidità e resistenza meccanica, sia in trazione che in compressione, ma presentano degli svantaggi, tra cui un aumento del peso (+20-25%) e una riduzione dell'elasticità rispetto alla versione standard.

There are different variants of polypropylene, including fiber-reinforced ones, designed to enhance certain mechanical properties of the material. Fiber-reinforced polypropylenes offer increased rigidity and mechanical strength, both in tension and compression, but have some drawbacks, including an increase in weight (+20-25%) and a reduction in elasticity compared to the standard version.

The two main types of fiber-reinforced polypropylene are:

• PP-CF reinforced with carbon fiber: This type of polypropylene is extremely rigid and strong but is very expensive, making it less accessible for some applications.
• PP-GF reinforced with glass fiber: This variant is also very rigid and strong, though more affordable compared to the CF (carbon fiber-reinforced) version.

However, in my opinion, it may be more advantageous to opt for fiber-reinforced nylon when choosing between these two types of fiber-reinforced polypropylene. Reinforced nylon offers a good balance of rigidity, strength, and cost, making it a versatile and more economical choice for many applications.