Rogue has spent the last 5 years and over $2,000,000 in scientific testing, research, and development to make our bars more durable than any other bars on the market. We have optimized our materials and manufacturing processes. We also developed a proprietary, patent pending process we call Rogue Work Hardening (RWH™). Barbells treated with RWH™ are more resistant to the stresses of being repeatedly dropped. Rogue launched this project because of an unprecedented change in the manner in which barbells are used.
The widespread introduction of high repetition Olympic Weightlifting movements resulted in extraordinary increases in the demands placed on bars. Rogue has also developed a clear and meaningful scale for rating barbell durability that makes it easy for you to choose the correct barbell for your application.
Read more about the science of RWH™ and the F Scale™ here.
The first step was to optimize our steel alloys’ chemical and mechanical properties. Barbells with low tensile and yield strength are more likely to bend with normal use. Tensile and yield strength that is too high can be detrimental, making the metal brittle.
The second step was to rethink barbell coatings. Chrome has been the “gold” standard of barbell plating for many, many years. Rogue’s exhaustive scientific analysis has shown conclusively that chrome decreases the durable lifespan of barbell shafts. Chrome remains an excellent, wear resistant sleeve coating and Rogue will continue to use it for this application.
The final step was to find a way to make our barbells resistant to the stresses of being dropped. To this end, Rogue developed the proprietary, patent pending process Rogue Work Hardening (RWH™). Thousands of hours of independent scientific fatigue testing and analysis demonstrate conclusively that Rogue barbell shafts treated with RWH™ have improved durability and last longer than untreated bars when subjected to the stresses of being dropped.
Read more about Rogue Barbell durability improvements here.
Dropping the bar during Olympic weightlifting produces far more stress on a barbell shaft than traditional bodybuilding movements and powerlifting movements. It follows then that historically, the bars subjected to the greatest stresses were in Olympic Weightlifting training centers. Bars at large facilities were dropped 10,000-20,000 thousand times per year.
Around 2005, high repetition Olympic Weightlifting movements gained popularity and bumper plates became more readily available. From that point on it became common for bars to be dropped up to 150,000 times per year in gyms. This is up to a 15x increase in drops.
Read more about the history and evolution of barbell use here.
Because of the extraordinary change in barbell usage, we decided to consult with the failure analysis engineers at SEA Limited, a world leader in consumer product testing, to learn about the stresses that are placed on a barbell when dropped.
To determine these stresses, electronic strain gauges were attached to the shaft of a barbell and the bars were dropped from overhead.
Read more about the determination of the stresses placed on a barbell here.
SEA found that the greatest stress on a barbell shaft is caused not by heavy weight loads, but by the unsupported / unloaded end of the sleeve continuing its downward momentum after the plates have hit the ground from an overhead drop. As seen in the illustrations below, the stress will continue to increase as the unsupported length of sleeve increases
Naturally then, when the barbell sleeve is shorter in overall length (such as those on a C-70S Short Bar) the force of the unsupported end of the sleeve is less. A similar situation is found when a standard length sleeve is supported by additional plates and is able to remain more level when the plates hit the ground. Both of these situations greatly reduce the stress on the shaft when the bar is dropped.
Understanding that weight loads don’t dictate stress can affect how we look at typical barbell usage. For example, in a gym that practices mainly high-repetition, low weight Olympic Weightlifting movements (65-135 LBS), the highest number of cycles are actually placed on barbells at their highest levels of stress, with long lengths of unsupported sleeves. To put it in another perspective, the drop of a standard men’s bar with relatively light weight (shown in the video on the right) causes much more measurable stress than the lift and drop of an Elephant Bar™ loaded to over 1,000 LBS.
Unsurprisingly, lifts that are not dropped—even extremely heavy ones—also cause far less stress than lifts that are dropped.
Read more about what causes stress to a barbell here.
Once Rogue determined the stresses that are placed on barbells, the engineering team used a 4 point bend test to simulate this stress in a testing environment. The sample is fixed at the ends and the load is delivered by two pins, two inches apart. This load is cycled several times per second.
Read more about the determination of the stresses placed on a barbell here.
Choosing the right barbell can be difficult. There is no industry standard for reporting barbell properties. Therefore, you are presented with an array of numbers which vary by manufacturer and very often do not provide useful information. Rogue has developed a clear and meaningful scale for rating barbell durability that makes it easy for you to choose the correct barbell for your application.
By testing finished barbell shafts using the 4-Point Bend Test at a stress level appropriate for the bar’s sleeve type, we are able to assign a durability rating or F Rating™ to each barbell. Performing the test in this manner accounts for all of the factors that contribute to barbell durability when subjected to the forces of being dropped from overhead. More specifically, the F Rating of a barbell is directly correlated to the number of cycles the shaft lasts in the 4-Point Bend Test, when tested at a stress level appropriate for the type of sleeve used on the bar.
Read more about the F Scale™ here.
How a barbell is used will affect its durable lifespan, and it’s a key factor in determining what type of F Rating™ might be suitable for your gym’s needs.
As we’ve established, dropping a bar from overhead causes more stress on the shaft than traditional bodybuilding or powerlifting movements. A barbell used primarily for slow lifts will typically last much longer than the same barbell used for Olympic Weightlifting. Bars used in commercial facilities will also see more volume and therefore more cumulative stress than barbells used by single athletes.
This graph correlates the F Rating™ of a barbell with different types of usage in order to predict the durable lifespan. Using this data, we are able to make recommendations on what F Rating™ is appropriate for different training situations.
By correlating the factors that affect barbell durability with our test data, we can assign an F Rating™ to a barbell. From the F Rating and the type of use, we can predict the bar’s durable lifespan.
Rogue has improved the durability of our bars and has created a clear and meaningful industry standard for the durability rating of barbells. The big winner with this scale is customer. Rather than relying on a meaningless static strength rating or trying to make sense of tensile and yield strength, you can know how durable your bar is compared to other bars on the market. Our hope is that the F Scale™ will expand beyond Rogue to allow customers use F Ratings™ when choosing the right barbell for their application regardless of the manufacturer.
Read more about the research and development that went into creating the F Scale™ here.