Hard Rock Drills

Engineered for Reliability. Manufactured for Availability.

In the last 40 years Boundary’s CAT/Bucyrus drill undercarriage has been tested in the most challenging mining regions in the world and demonstrated the highest level of performance. Engineered in-house with the highest standards in material and innovation, manufactured to ensure timely supply.


Track Shoes

Our MD6640 track shoes have been optimized for reliability.

Cast in a proprietary alloy to achieve hardness levels exceeding industry standards.

The material has been designed to have an impact value suitable for mining operations in Canada, United States, Chile, Peru, Africa and anywhere else in the world.

100% interchangeable with OEM.


Drive Tumbler

Manufactured in a proprietary alloy to ensure reliability, wear life and lower cost of ownership.

Fits MD6640 cast undercarriage and Bucyrus 49R, 49RII, 49RIII and 49HR.

100% interchangeable with OEM.



Optimized material and heat treatment processes to extend life.

Forged and hardened to 40 HRc.

Proven modified manganese bronze bushings.

100% interchangeable with OEM.


Mast Rack & Pinion

Optimized material and heat treatment processes to extend life.

Boundary’s mast pinions are manufactured from forgings before going through a series of proprietary heat treatment steps to extend life.

Boundary’s forged mast racking and pinions are 100% interchangeable with OEM.



We’re proud to put the Boundary mark on the mining replacement parts and equipment that we sell. All products and services we offer come with a full guarantee. If it’s not right, we’ll be there to make it right. We want you to use Boundary mining products with confidence.

  • Models We Service

    CAT MD6640

    Bucyrus 49HR

    Bucyrus 49RIII

    Bucyrus 49RII

    Bucyrus 49R

  • Undercarriage

    Track Shoes

    Front Idlers

    Drive Tumblers

    Lower Rollers

    Top Rollers

    Pins & Bushings


  • Transmissions

    Propel New/Rebuild

    Rotary New/Rebuild

    Pulldown New/Rebuild

  • Other

    Mast Racking

    Mast Pinion



Large Gearbox Rebuilds

Rebuild or refurbish to get the most out of your gearbox