Inverter Roller 115 – (NO Trigger, ErmesSub-Compatible) with Stainless Steel Accessories

Inverter Roller 115 – (NO Trigger, ErmesSub-Compatible) with Stainless Steel Accessories

The model presented has been developed to be fast and easy to handle, particularly suitable for quick and instinctive shots.

3D Model for Speargun and Handle

Designed for engraving on exotic woods such as teak, iroko, and mahogany.
The included files also feature .STEP and .STL formats for the accessories, which can be 3D printed or CNC-machined from plastic materials such as Delrin.

Included DXF Projects

Among the various DXF files, you’ll also find:

• Ballast slot covers
• Rubber tensioners with reel (see photos)
• Muzzle accessories
• Handle plates
• Butt plates

All DXF files come with technical drawings in PDF format, including instructions and dimensions for sheet metal folding and other machining processes.

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

Speargun Machining

The 3D model is designed for engraving on hardwoods. We recommend using 3- or 4-flute bits specifically made for wood.
Using general-purpose bits or those designed for metal or plastic may cause chipping or imperfections.

With a shaft stroke of 115 cm, the speargun is suitable for all types of spearfishing, including ambush-style hunting.

Important Note – ErmesSub Trigger Compatibility

The speargun is compatible with two ErmesSub trigger systems: Swings Double Roll and Future, including the more compact Future Double Roll.
Although the project was initially designed for the LDpro3D trigger system, the external dimensions are highly compatible with ErmesSub triggers as well.
As shown in the photos, structural compatibility is excellent.
Installing the ErmesSub Swings or Future systems requires only minor, non-invasive modifications that do not significantly alter the original design.
If you opt to use the LDpro3D trigger system, we strongly recommend purchasing the full set of files to ensure proper assembly and operation of the mechanism.

Important Note – Wood Preparation

The speargun structure is particularly slim. It is recommended to build a lightweight laminated blank using Okoumé strips to reduce specific weight and maintain proper buoyancy in the water, avoiding sinking.
Use hardwoods like teak, iroko, or mahogany for the central and lateral strips (the width of the central strip should match the distance between the pulley housings at the muzzle).

Inverter Roller System and Performance

With the inverter roller system, the shot’s power and range are superior due to increased shaft travel and acceleration.
Moreover, the inverter system reduces recoil by up to 70% during the shot, making the speargun more precise, stable, powerful, and fast.
The inverter section of the rubbers is hidden inside the barrel, while the lower section is almost completely concealed—reducing the thickness of the loaded weapon and improving handling and swing speed.

To further reduce bulk, we recommend using the Croco block (included in the DXF files) with reel , along with the Stopper also included in the files. The muzzle housing is designed for the stoppers provided in the DXF; other stopper types may require manual modifications.

Handle Finishing

Once engraved, the speargun is ready for assembly.
The only manual operation required:
Sanding and shaping the grip saddle where the gluing was done (highlighted in pink in the photos). This part has not been pre-shaped to allow each to adapt it to their own hand.

Three handle sizes are included (small, medium, large).

The handle can also be engraved on plastic materials such as Delrin or glass-filled nylon. In this case:

• Do not use epoxy resins
• Use D4-class polyurethane adhesives for optimal bonding
• Sand the plastic surfaces before gluing

Main Model Dimensions:

• Muzzle height: 26 mm
• Muzzle width: 55 mm
• Max belly width: 90 mm
• Max belly height: 30 mm

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

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

Included PDF Technical Drawings:

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

WARNING:
This project is intended for private and recreational use only.
It is ed under the domain LDpro3D, owned by Lombardo Davide.
Any commercial reproduction is strictly prohibited.
Violations will result in legal action.

Technical Note:
Specifications and parameters for laser cutting and CNC milling depend on the type of machine and the operator’s preferences.
Standardized settings cannot be provided without knowing the equipment used.