Inverter Roller 60, for ErmesSub Double Roller Wing Trigger, with Stainless Steel Accessories (Update with second ergonomic handle)

Inverter Roller 60, for ErmesSub Double Roller Wing Trigger, with Stainless Steel Accessories

The model presented was developed as a unique and compact speargun, slimmer than 85+ cm models, fast and easy to handle, particularly suitable for instinctive quick shots and for cave or murky water hunting.
Designed specifically for fishing in very murky waters, where shot speed is essential for a successful catch.
This small inverter is part of the Compact Line, along with other models.

3D Model for Speargun and Handle

Designed for machining on exotic hardwoods such as teak, iroko, and mahogany.
The package includes .STEP and .STL files for the speargun (ready for CAM software), as well as STL and STEP files for the accessories, compatible with 3D printing and CNC machining using plastic materials like Delrin.
The butt plate was designed with a futuristic and functional aesthetic, also helping to improve aiming alignment.

Included DXF Projects

Among the various DXF files, you’ll find:

• Covers for ballast slots
• Tensioners with reel support (see photos)
• Muzzle accessories
• Handle plates
• Butt plates
• Handle ballast plates

All DXF files are accompanied by PDF technical drawings with bending instructions and dimensions for sheet metal work and other processing.

Also included are DXF and PDF files for the stainless steel stopper, which can be produced by stainless steel laser cutting or CNC milling on carbon fiber.
DXF files can also be used for CNC cutting on carbon fiber panels, if you prefer to make the accessories without any bending.

Speargun Machining

The 3D model is designed for engraving on hardwood. We recommend using 3- or 4-flute tools specifically for wood.
Using generic tools or those designed for metal/plastics may cause chipping or imperfections.

With a 70 cm shaft stroke, the speargun is suitable for all types of spearfishing, including ambush, murky water, and hole fishing.

ErmesSub Double Roller Wing Trigger

Specifically designed to house the ErmesSub Double Roller Wing trigger system, the slot ensures perfect compatibility.
Considering the frequent updates Ermes makes to its trigger systems — often involving changes to the upper locking tabs — the slots have been widened.
This ensures that future updates will not compromise the ease of installation or system stability.

Important Note – Wood Preparation

Due to the slim structure, we recommend using light laminated blanks with Okoumé strips to maintain optimal buoyancy.
The central and side strips should be made of teak, iroko, or mahogany.
The width of the central strip must match the distance between the muzzle pulley slots.

Recommended strip configuration (right to left or vice versa):

Iroko (or Teak)
Okoumé
Iroko (central strip)
Okoumé
Iroko

Inverter Roller System and Performance

Thanks to the inverter roller system, both power and range are enhanced due to greater acceleration and shaft travel.
Additionally, the inverter system reduces recoil by up to 70%, making the speargun more accurate, stable, powerful, and fast.
The inverter section of the bands is hidden inside the barrel, and the bottom is almost fully covered — reducing the bulk of the armed gun and improving maneuverability and tracking speed.

To further reduce bulk, we recommend using the Croco block (included in the DXF files) with integrated reel support, along with the included stopper. The muzzle slot is designed for the stoppers provided in the DXFs; other models may require modifications.

Handle Finishing

Once machined, the speargun is ready for assembly.
The only manual operation required: sanding the glue points or adjusting the handle to your hand shape.

Ergonomic handle in one size (M–L), suitable for most users.

The handle can also be made in materials like Delrin or glass-filled nylon. In that case:

• Do not use epoxy resins
• Use polyurethane adhesives of class D4
• Sand the plastic surfaces before gluing

Update – October 12, 2025

The October 12, 2025 update introduces a second handle, slightly larger and more ergonomic, available in addition to the standard simple handle.
Users can now freely choose between the two versions.

In the photos, the new handle is highlighted in light blue.

No modifications are required to fit the new handle, except for the Snake and Hybrid models, which may require light sanding of the saddle.

Main Dimensions of the Model:

• Total length: 830 mm
• Muzzle height: 27 mm
• Muzzle width: 57 mm
• Max body width: 75 mm
• Max body height: 32 mm

Included Files (STEP, STL, and DXF formats):

• Speargun
• Handle
• Handle plate
• Butt plate
• Threaded bushings (ballast slots)
• Ballast slot covers
• Line guide
• Inverter pulleys
• Roller pulleys (muzzle)
• Stopper
• Muzzle pulley cheeks
• 3x Tensioners with reel support

Included PDF Technical Drawings:

• Croco x3 with reel support
• Muzzle and inverter pulleys
• Muzzle accessories
• Stopper

WARNING:

This project is intended exclusively for private and recreational use.
It is registered under the domain LDpro3D, owned by Lombardo Davide.
Any reproduction for commercial purposes is strictly prohibited.
Violations will be legally prosecuted.

Technical Note:

Laser cutting and CNC machining parameters vary depending on the machine type and operator preferences.
It is not possible to provide standard settings without knowing the equipment used.