Virtual Tour – Part 6: Propellers

A technician puts finishing touches on a 5-blade CNC Cleaver sterndrive propeller.
Checking blade thickness on a classic 3-blade outboard cleaver.

Continuing from Virtual Tour Part 5: Sterndrives, Transoms & Accessories…we will visit the Mercury Racing Propeller Department’s finishing area.

People are fascinated with propellers. The response to Scott Reichow’s Prop School blog series proves people are craving to learn more. Our visitors are a bit surprised when they enter Racing’s propeller finishing area. I think they are expecting to see a number of robotic machines pumping out finished propellers. Nope. What they do see is highly skilled craftsmen creating precision tuned works of art. Each puts their finishing touch on every propeller Racing makes – including our CNC machined Sterndrive Cleavers.

Lab Finished props gave Team Mercury a competitive edge in the outboard factory war days of tunnel boat competition.
Have props, will travel. A classic photo of Mercury’s mobile prop lab during the golden era of outboard factory tunnel boat racing.

The trademark, “Lab Finished,” was created by Mercury Racing back in 1970s – when factory outboard racing required a dedicated Engineering Lab to create specialized props. We have proven through the years that hand-working a prop enhances performance. This is particularly true for props run at elevated transom heights (surface piercing) and higher RPMs where impact-induced vibrations and other nuances are amplified.

Only a small percentage of our propeller line is designed specifically for racing. Our most popular propeller is mostly used for recreation: the Bravo I. We first enhanced performance of this MerCruiser sterndrive propeller by lab finishing them for racing.

For a mere $600, a twin engine catamaran similar to this Spectre gained five MPH in top-end speed as a result of Mercury Racing’s Lab Finishing work on a set of stock Bravo I propellers.
Andy grinds on a Bravo I propeller casting as it is received from Mercury’s propeller foundry.

A magazine once set out to explore the benefits of Mercury Racing’s Lab Finishing work. A set of stock Bravo I propellers were run on a recreational catamaran powered by twin Mercury Racing 575SC sterndrives. These props were sent back for our craftsmen to work their magic. The boat gained five mph! The cost for such a performance gain? A mere $600! (Similar performance gains through an increase in horsepower would have cost thousands of dollars).

More recently, Scott and his team have made additional tweaks to Mercury’s base Bravo casting to provide a new performance level for a variety of 2-stroke and 4-stroke outboard applications.

David heats up a Bravo Three XR casting to add blade cup. The added cup is particularly beneficial with diesel applications.
David preps a Bravo Three XR casting for finishing work on the grinding wheel.

Our propeller team has also created custom, counter rotating Bravo Three XR propeller sets for a variety of MerCruiser Bravo Three drive applications. We initially developed these precision tuned props for the U.S. sport cruiser market. They have grown to become very popular throughout the world in both gas and diesel applications as well.

This concludes our 6th in a series about Mercury Racing’s Plant 36 manufacturing facility. I hope you have enjoyed the tour. I’m sure you have gained an appreciation for our products and the people who make them.






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9 thoughts on “Virtual Tour – Part 6: Propellers”

  1. How many parts in total are there in total to the virtual tour? I am thoroughly enjoying it so hopefully many more… Thanks guys!

    1. Thanks, Ryan. Glad you’re enjoying the tour. There’s lots to share, but we plan to hit only the highlights. We’re already at “Part 6” of an expected 4 part series. Maybe Part 7 on CNC props, but that’s about it – for now.

  2. Hi guys,

    Are these videos available to distributors for use in traing or dealer service conferences ? If so how do we get hold of them ?
    We will be attending the Miami Service Conference at Hawks Cay in Feb , can we get copies all these types of videos ?/

    Thank you.

    1. Hi Lee,

      The entire Virtual Tour video series is live on our YouTube channel, Let me know if you prefer other file formats for loading on thumb drives or DVD and I can get those to you for your conference.


      1. Hi Rick,

        Thank you for the reply.
        I would prefer to have them on memory sticks or even on a DVD, i would like to use them during our training sessions.

        If you could send some down to Duck Key in Feb that would be great, or if they can be posted directly at E.P.Barrus ??

        Thank you again.

        1. No problem, Lee. I’ll send you the files via FTP. I’m sure we’ll have memory sticks for the Miami show. I’ll put them on a couple of those for you as well.


          1. No problem. I’ll FTP them to you now. I’ll also put them on a memory stick for Pete Coen to bring with him to the service conference for you.

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