PHD Sleds for Snowmobiles: Design and Manufacturing

Expert overview: design and manufacturing of durable PND sleds for snowmobiles.

Building sleds for snowmobiles is not about aesthetics or shape. It’s a true engineering challenge, where the material, load calculations, welding technology, and understanding of operating conditions play the central role. Below is a real project of PND sleds, designed to meet specific operational requirements.

Operating Conditions

The sleds are designed for forest work and are towed by a snowmobile. Key conditions include:

• sub-zero temperatures,
• movement across untracked snow and rough terrain,
• dynamic loads during acceleration and braking,
• payload up to 400 kg.

Under these circumstances, the design must not only be strong, but also predictable and serviceable.

Material Selection and Thicknesses

The primary material is PND (low-density polyethylene), chosen for:

• maintaining toughness down to −60 °C,
• high impact resistance,
• low friction on snow,
• suitability for extrusion welding, forming a monolithic, seamless structure.

Different thicknesses were applied according to the function:

• 8 mm PND — bottom, sides, and storage boxes. This ensures structural rigidity under both static and dynamic loads while preserving material elasticity.
• 6 mm PND — front visor. The visor is non-structural, so reducing thickness lowers weight without compromising function.

This approach balances strength, weight, and service life.

CAD Design

The sleds were fully designed in CAD software using a parametric model, specifying:

• overall dimensions (body length — 2200 mm, side height — 400 mm, visor height — 500 mm),
• material thicknesses,
• bend radii,
• welding zones.

The CAD model allowed us to:

• assess load distribution,
• avoid stress concentrators,
• ensure weldability and assembly feasibility.

The model underwent approval until all elements were logically and structurally coordinated.

Bottom and Runners

The bottom is 8 mm PND, designed for distributed payload.

For durability and smooth sliding, three longitudinal runners were welded to the bottom:

• Width: 100 mm each,
• Material: same PND as the main body.

Runners provide:

• reduced friction on snow,
• abrasion resistance,
• improved longitudinal rigidity,
• better tracking stability.

Using three runners ensures stable behavior without excessive drag.

Sides, Visor, and Load-Bearing Scheme

• Sides (8 mm PND): take lateral loads during turns, slopes, and rough terrain.
• Front visor (6 mm PND): protects cargo from snow and reduces snow ingress, without overloading the front.

All elements are joined by extrusion welding, forming a single, cohesive unit.

Storage Boxes

Two welded storage boxes are included:

• Rear: for a chainsaw,
• Front: under the visor, with a lid for snow protection.

Both are 8 mm PND and contribute to overall body stiffness.

Flat Pattern and CNC Cutting

After CAD modeling, flat patterns for all parts were prepared considering:

• weld allowance,
• material thermal expansion,
• assembly sequence.

CNC cutting ensured:

• precise geometry,
• clean edges for welding,
• minimal adjustments during assembly.

Extrusion Welding

Assembly used extrusion welding with PND welding rods.

Temperature ranges:

• edge preheating: 210–230 °C,
• rod melt: 220–240 °C,
• extruder air: 260–300 °C.

Sequence:

1. Bottom,
2. Runners,
3. Sides,
4. Front section and visor,
5. Storage boxes and internal reinforcements.

Welds cooled naturally.

Tow Hitch and Shock Absorption

The tow hitch is made from steel profile tubing, with a pivoting design to allow smooth movement over uneven terrain.

A spring-based damping mechanism reduces:

• jolts during acceleration,
• impact loads during braking,
• stress on the sled body and hitch.

Result

The result is a sled:

• engineered for real operating conditions,
• tailored to specific requirements,
• designed according to material technology rather than “template” methods.

This approach produces sleds that require no constant maintenance, performing reliably in challenging environments.

Flat Patterns and Technical Drawings

For anyone looking to manufacture these sleds themselves, accurate technical drawings and flat patterns are essential.

You can order:

• ready-to-use flat patterns and technical drawings for sleds 900 × 2200 mm,
• custom CAD projects based on your sketch or photo.

We can:

• adapt the design to your snowmobile or motorized tow vehicle,
• adjust the front section shape,
• add reinforcing ribs,
• prepare flat patterns for CNC cutting.

You provide the sketch or photo, and we deliver a complete set of CAD drawings and flat patterns ready for manufacturing.

Leave a message to discuss the details.