45mm Square Stub Insert

SKU: N/A Category: Axles Brand: Couplemate

Price

Price range: $65.00 through $67.00 Inc.GST

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Stub Insert Installation & Alignment Guide

45mm Square Steel Stub Insert (Fits 50mm x 50mm Box Section)

How to Install (Step-by-Step)

1. Prep and deburr the box section: Cut your **50mm x 50mm box section** perfectly square, then use a file or grinder to thoroughly deburr the inside edges and remove any internal weld seams that might obstruct the insert.
2. Drill plug weld holes: Drill two or three 12mm holes into the sides of the **50mm box section** approximately 50mm back from the edge; these will act as critical plug weld points to secure the body of the insert.
3. Seat and square the stub insert: Drive the **45mm square stub insert** firmly into the box section until it reaches the desired depth, checking with a square tool to ensure the axle spindle remains perfectly straight and parallel to your chassis line.
4. Weld the perimeter and plug holes: Weld completely around the external joint where the box section meets the stub shoulder, then completely fill your pre-drilled plug holes with deep-penetration structural welds.
5. Cool slowly and coat: Allow the completed assembly to cool naturally at room temperature to avoid making the steel brittle, then apply a cold-galvanising spray or rust-preventative paint to the bare metal areas.

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45mm Square Steel Stub Insert (Fits 50mm x 50mm Box Section)

Heavy-duty steel stub insert engineered for seamless splicing, extending, and reinforcing of standard 50mm square hollow sections (SHS).

Product Description

This premium 45mm x 45mm square steel stub insert is the industry standard solution for joining or extending 50mm x 50mm Square Hollow Sections (SHS). Manufactured from high-tensile structural steel, it provides maximum joint rigidity and strength. The raw steel finish ensures it arrives ready for immediate, clean welding without the hassle of grinding off coatings or exposing fabricators to hazardous galvanised fumes.

Perfect for heavy-duty fabrication projects, this insert is widely used in trailer chassis manufacturing, extendable drawbars, agricultural equipment repairs, and modular structural framing. Its precision-milled dimensions guarantee a snug fit inside your box section, eliminating excessive play and ensuring precise alignment.

Key Features

Perfect Compatibility: Engineered explicitly to slide inside 50mm x 50mm external square hollow sections.
Snug Precision Fit: The 45mm x 45mm outer profile ensures minimal tolerance play inside standard 2.0mm to 2.5mm wall thickness tubing.
Heavy-Duty Structural Integrity: Crafted from high-tensile steel to withstand high load-bearing and towing forces.
Weld-Ready Finish: Supplied in clean, raw/uncoated steel for instant, high-penetration welding.
Versatile Application: Ideal for trailer builds, hitch receivers, gate frames, and telescopic steel assemblies.

Technical Specifications

Specification	Detail
Insert Profile Dimensions	45mm x 45mm Square x 267mm Long
Mating Tube Requirement	50mm x 50mm Square Hollow Section (SHS)
Optimum Mating Wall Thickness	2.0mm to 4mm
Material Grade	Structural Carbon Steel (Weldable)
Surface Finish	Raw / Self-Colour (Uncoated)

Industry Standards and References

Steel Tube Dimensions: Manufactured to complement standard structural steel dimensions as outlined in InfraBuild Steel Sections Guides and international SHS standards.
Fabrication Compliance: Suitable for use in trailer manufacturing compliant with the Australian Design Rules (ADR) for light trailers and vehicle components.

Stub Insert Installation & Alignment Guide

45mm Square Steel Stub Insert (Fits 50mm x 50mm Box Section)

How to Install (Step-by-Step)

1. Prep and deburr the box section: Cut your **50mm x 50mm box section** perfectly square, then use a file or grinder to thoroughly deburr the inside edges and remove any internal weld seams that might obstruct the insert.
2. Drill plug weld holes: Drill two or three 12mm holes into the sides of the **50mm box section** approximately 50mm back from the edge; these will act as critical plug weld points to secure the body of the insert.
3. Seat and square the stub insert: Drive the **45mm square stub insert** firmly into the box section until it reaches the desired depth, checking with a square tool to ensure the axle spindle remains perfectly straight and parallel to your chassis line.
4. Weld the perimeter and plug holes: Weld completely around the external joint where the box section meets the stub shoulder, then completely fill your pre-drilled plug holes with deep-penetration structural welds.
5. Cool slowly and coat: Allow the completed assembly to cool naturally at room temperature to avoid making the steel brittle, then apply a cold-galvanising spray or rust-preventative paint to the bare metal areas.

Additional information

Weight	2 kg
Dimensions	26 × 5 × 5 cm
Seal Shoulder	Electric, Marine

Our Service Lifetime Warranty

Our goods come with guarantees that cannot be excluded under the Australian Consumer Law. You are entitled to a replacement or refund for a major failure and compensation for any other reasonably foreseeable loss or damage. You are also entitled to have the goods repaired or replaced if the goods fail to be of acceptable quality and the failure does not amount to a major failure.

Couplemate™ is a manufacturer and vendor of high-quality towing, trailer, and caravan components. Couplemate™ Core Goods and Custom Work are guaranteed to be free of defects for the service lifetime of the product when used as intended.

Warranties are non-transferrable and Couplemate™ requires satisfactory proof of purchase prior to issuing a remedy. The full Couplemate™ Warranty Policy can be found in the Terms & Conditions: Section 8 – Consumer Guarantees & Warranty.

Warranties are in addition to your rights under the Australian Consumer Law. If something is wrong with your order, please contact our team.

60-Day Returns

After 60 years of experience, we know that life has its unpredictable moments.

All Couplemate™ orders (online, over the phone, or in-store) have a 60 day period for change-of-mind returns and exchanges. There are some items that can’t be returned and some returns may incur a 15% restocking fee.

You can view our full policy for change-of-mind returns here.