DOCOL R8 Advanced High Strength Steel 1 "a"


DOCOL R8 Advanced High Strength Steel


DOCOL R8: The State of the Art in Advanced High-Strength Steel

A few years ago, while attending PRI (the Performance Racing Industry trade show in Indianapolis), we were introduced to a newly-developed steel tubing product called Docol R8. It was designed to replace 4130 Chrome-Moly -- a World War II-era product -- in race car chassis and safety cage construction. We were intrigued. 4130 has always had its drawbacks as a metal used for impact absorption. It tends to get brittle when welded, and it lacks ductility (the ability to sustain plastic deformation under tensile stress before failure.)

Docol is a modern, engineered Dual Phase Advanced High-Strength Steel (AHSS), replacing 4130 as the state-of-the-art material for race car chassis and safety cage manufacturing. We found that racing fabricators were switching to Docol R8. Engineered specifically for motorsports applications, Docol R8 is an improvement over 4130 in every way:

  • Docol R8 is considerably stronger than 4130 CrMo. Tensile Strength of 116,000 psi vs 95,000 psi, Yield Strength of 100,000 psi vs. 75,000 psi.
  • Docol R8's heat-affected zone (HAZ) is much smaller, meaning much less joint embrittlement from the heat of TIG welding.
  • Docol R8 has a higher resistance to fatigue.
  • Docol R8 is much more tolerant of heavy fabrication (such as tube bending and forming).
  • Docol R8 is far more dimensionally consistent, with tube diameter variance of 0.3% vs. 10.0% in 4130 and wall thickness variance less than 1/3 that of 4130.

So after extensive research, consultation with testing engineers, and discussion with professional race car fabricators, Competition Motorsport was the first major manufacturer to transition fabrication of all our bolt-in roll bars and harness bars from using 4130 CrMo to Docol R8.

That was in 2018, and five years later we have had nothing but great experience with, and feedback about, Docol R8. Fortunately, we haven't had many customers tell us about accidents they've had that put the strength of their CMS Performance roll bar to the test. But we have had a couple. In one case in particular, a customer told us his CMS roll bar saved him from significant injury. He was hit broadside at an angle just behind the driver seat -- basically, right into the meat of the main hoop of his roll bar -- and the offending car didn't protrude into the cockpit even an inch further.

Our own drivers have been amazed at the strength of Docol R8 under race conditions. We've had our share of race car "rubbing", and the parts fabricated from Docol are always amazingly intact.

Is Docol more expensive than 4130? A little. But our prices have remained unchanged, because we believe in delivering a superior product at a competitive price. That gives us an edge, and it gives our customers an edge. That's why we design and manufacture every roll bar in-house, starting with straight bar stock and ending up with a beautifully TIG-welded roll bar. It's why we powder coat each one in our professional powder booth, on-site. And it's why we use advanced materials like Docol R8.

We don't farm any of it out, because when we put our name on a piece of safety equipment, and we ask you to bolt it in your car and take it to the track, we don't take chances. The result is superior design, quality, and service, that you simply can't find anywhere else. You can pay more for a roll bar, but you can only get the best from CMS. Check out all CMS Roll Bars here.

Feel free to give us a call at (844) 438-7244 or drop us an email if you want more info about Docol R8 vs 4130 CrMo, or if you want to discuss what roll bar is right for you!

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We’ve sold tens of thousands of helmets here at Competition Motorsport and, in the process of doing that, answered a million questions (probably) about them. With that in mind, this article will give you the real lowdown on selecting a proper auto racing helmet. We’ll go over the why’s and how’s of size, shape, certification, pricing, features, and maintenance so you have the tools you need to select the perfect helmet.

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