Bruntons SigmaDrive is a brand new 21st Century solution that is already an award winner and provides effective anti-noise and anti-vibration solutions of the highest order. What makes SigmaDrives different is their ability to resist propeller thrust when installed as a standalone coupling, directly from the shaft to the output flange on the engine’s transmission. It reduces and even eliminates vibrations that originate from an imperfect alignment between the propeller shaft and the engine, compensating for up to 3 degrees in all directions. This system can also be installed using thrust bearings so that the engine can be placed utilizing the space available ergonomically.

Many products exist which attempt to solve the problem of good propeller shaft alignment with varying degrees of success. They may use rubber couplings, cardan units or thrust bearings, however the SigmaDrive is only way to truly solve the problem. It uses special constant velocity joints that are able to resist the propeller thrust without the need for thrust bearings. They are extremely compact and able to transmit higher torque than other couplings with similar dimensions.

Bruntons sigmadrive

SigmaDrives are designed to fit virtually all boats from yachts to workboats, military vessels to sailboats; in fact pretty much any powered vessel with engines up to 1300hp. They are extremely easy to fit, requiring no modifications to the craft, which can usually be equipped with the drive unit whilst still in the water. Together with its anti-noise and vibration abilities having a SigmaDrive on your vessel also ensure that seals and bearings are always perfectly aligned, reducing wear and guaranteeing a longer trouble-free life for all associated components.

Manufactured from a special bronze alloy, SigmaDrives are a premium product requiring virtually no maintenance and containing no bearings or rubber in their construction. In addition to requiring little maintenance themselves, fitting one also means considerably reduced maintenance will be necessary on other stern gear components.

  • Compact size, comparable to a standard shaft coupling.
  • Provides perfect alignment for the propeller shaft and works perfectly in line or out.
  • Easy and quick to fit, usually without slipping the vessel and without the need to modify the propeller shaft, or fit fixture plates or brackets for thrust bearings that are no longer required.
  • Contains no rubber or bearings, and is manufactured from a special alloy that ensures long life with little maintenance requirement.
  • A highly cost effective solution requiring little or no costly modifications to the vessel.

To see SigmaDrive in action watch our 1 minute video below!

sigmadrive coupling types

Shown above is the Jet Drive (left), the standard drive (center) and the thrust drive (right).