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Old 02-18-2013, 02:55 PM   #1
Eric Huesman
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PSI on Vulcan and/or Hammerhead CrossFit Bar

Does anyone know what the PSI tensile strength rating is on either the Vulcan or Hammerhead CrossFit bars? I know they are both made by the same Taiwanese manufacturer, but the specs are slightly different so I can assume the PSI will be different. I emailed Hammerhead and Vulcan a couple days ago, but have not received a response from either one. Maybe due to the holiday weekend.

The only information regarding "strength" of the bar that I could find is on their own websites, where Hammerhead states their bar has a 700lb weight capacity, and Vulcan shows a video of their bar withstanding a 1500lb static strength test. The issue I see with that static test is that the bar is being deflected at two points at the same time, versus deflecting the bar at a single point in the center (the way Ivanko tests their bars). I don't know for sure that it makes a difference, but to a layman it seems common sense that a material can withstand more pressure when it is divided between two points versus one. Any physicists on here that can clear that up?

Thanks in advance!
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Old 02-18-2013, 08:07 PM   #2
Steve Jaeger
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Re: PSI on Vulcan and/or Hammerhead CrossFit Bar

Eric,

The tensile strength of the Hammerhead bars is at 110,000 PSI. The Yield strength is at 100,000 PSI.

They have a static capacity of 700 lb without bending or deforming.

And we do have a lifetime warranty on them against bending/breaking with normal use.

Thanks for asking,
Steve
Hammerhead Fitness
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Old 02-18-2013, 08:46 PM   #3
Eric Huesman
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Re: PSI on Vulcan and/or Hammerhead CrossFit Bar

Thanks for the information Steve.
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Old 02-18-2013, 09:38 PM   #4
Jeff Enge
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Re: PSI on Vulcan and/or Hammerhead CrossFit Bar

Quote:
Originally Posted by Eric Huesman View Post
Does anyone know what the PSI tensile strength rating is on either the Vulcan or Hammerhead CrossFit bars? I know they are both made by the same Taiwanese manufacturer, but the specs are slightly different so I can assume the PSI will be different. I emailed Hammerhead and Vulcan a couple days ago, but have not received a response from either one. Maybe due to the holiday weekend.

The only information regarding "strength" of the bar that I could find is on their own websites, where Hammerhead states their bar has a 700lb weight capacity, and Vulcan shows a video of their bar withstanding a 1500lb static strength test. The issue I see with that static test is that the bar is being deflected at two points at the same time, versus deflecting the bar at a single point in the center (the way Ivanko tests their bars). I don't know for sure that it makes a difference, but to a layman it seems common sense that a material can withstand more pressure when it is divided between two points versus one. Any physicists on here that can clear that up?

Thanks in advance!
Ivanko's is technically a three-point stress test and Vulcan's probably four-point (though I haven't seen it to know, I just know a little about materials testing). The difference is that with a three-point test the stress is all on that concentrated point, while in the four-point the stress is taken in the length of bar between the points of force application.

Both are valid methods to find the stress-strain curve of a material, which is where you would get the yield and tensile strength values from.

There's also a very large safety factor built into any product engineered to bear load, especially commercial products. That 700# weight capacity Hammerhead gives is probably not nearly what the bar can actually hold, though I'm certainly not advocating overloading any bar.
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Old 02-18-2013, 09:46 PM   #5
Brad Allen Jones
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Re: PSI on Vulcan and/or Hammerhead CrossFit Bar

Did you look at Vulcan's bearing bar? They say the tensile strength is 195,000 PSI http://www.vulcanstrength.com/product-p/vstb-m.htm (WFS).

I know its not the same, but that looks like a pretty nice bar.
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Old 02-18-2013, 10:18 PM   #6
Eric Huesman
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Re: PSI on Vulcan and/or Hammerhead CrossFit Bar

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Originally Posted by Jeff Enge View Post
Ivanko's is technically a three-point stress test and Vulcan's probably four-point (though I haven't seen it to know, I just know a little about materials testing). The difference is that with a three-point test the stress is all on that concentrated point, while in the four-point the stress is taken in the length of bar between the points of force application.
I actually misspoke, or mis-typed as it is, I did not know how many points Ivanko used in their static test. I meant to say that Pendlay uses a single point. Or at least that is how I understand how they describe their testing:

"Material Testing Static Test - We take each bar and support it on the ends in v-blocks. We apply 2500 lbs of pressure in the center of the bar and deflect it 6 inches. They consistently return to true center within .000/.006 inches."

I guess "in the center" could be subjective though.

In regards to Vulcan, they have a video showing the 1500lb static test. The ends are secured and then a hydraulic press contacts the bar at two points underneath the bar and bend it upwards.

As long as all the tests are considered valid, as you state, then I don't care how many points are used to bend the bar.

Quote:
Originally Posted by Jeff Enge View Post
There's also a very large safety factor built into any product engineered to bear load, especially commercial products. That 700# weight capacity Hammerhead gives is probably not nearly what the bar can actually hold, though I'm certainly not advocating overloading any bar.
Well, just to be clear, 700lbs is more than I'll ever put on a bar. That being said, I don't think "700lb static test" is the same as "700lb capacity". Even the slow lifts are not static, and thus more pressure is actually being exerted on the bar than just the load. If I'm not mistaken, the working capacity of a bar is going to be somewhat less than the static test rating.

The president of IVANKO, Tom I. Lincir, kind of explains that in this article:

http://www.garageiron.com/How-Strong...rbell_b_8.html (WFS)

Quote:
Originally Posted by Brad Allen Jones View Post
Did you look at Vulcan's bearing bar? They say the tensile strength is 195,000 PSI http://www.vulcanstrength.com/product-p/vstb-m.htm (WFS).

I know its not the same, but that looks like a pretty nice bar.
It does look like a very nice bar, and no doubt is, but it is also well outside my budget.
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Old 02-19-2013, 08:04 AM   #7
Chris Diamont
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Re: PSI on Vulcan and/or Hammerhead CrossFit Bar

I live close to Vulcan and have bought their products. I could not be happier! I don't have a bar from them but I am getting there squat stand soon. There customer service is great for a pretty much one man show! He says lifetime warranty is not one filled with BS loopholes as many are. I like the bumpers I have. Can't tell a difference in them and the rogue HG's I have. Just my .02.
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Old 02-19-2013, 08:22 AM   #8
Jeff Enge
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Re: PSI on Vulcan and/or Hammerhead CrossFit Bar

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Originally Posted by Eric Huesman View Post
I actually misspoke, or mis-typed as it is, I did not know how many points Ivanko used in their static test. I meant to say that Pendlay uses a single point. Or at least that is how I understand how they describe their testing:

"Material Testing Static Test - We take each bar and support it on the ends in v-blocks. We apply 2500 lbs of pressure in the center of the bar and deflect it 6 inches. They consistently return to true center within .000/.006 inches." I guess "in the center" could be subjective though.

In regards to Vulcan, they have a video showing the 1500lb static test. The ends are secured and then a hydraulic press contacts the bar at two points underneath the bar and bend it upwards.

As long as all the tests are considered valid, as you state, then I don't care how many points are used to bend the bar.



Well, just to be clear, 700lbs is more than I'll ever put on a bar. That being said, I don't think "700lb static test" is the same as "700lb capacity". Even the slow lifts are not static, and thus more pressure is actually being exerted on the bar than just the load. If I'm not mistaken, the working capacity of a bar is going to be somewhat less than the static test rating.

The president of IVANKO, Tom I. Lincir, kind of explains that in this article:

http://www.garageiron.com/How-Strong...rbell_b_8.html (WFS)



It does look like a very nice bar, and no doubt is, but it is also well outside my budget.
Your quote I put in bold is the definition of a three-point bending stress test, just to get the semantics correct.

And yes, the working capacity of the bar is lower than the static test "rating." Saying your material can withstand a xxxx pound static stress test doesn't really tell you anything concrete about how strong the material is. It just tells you the quality control test that's done on every bar just to confirm that it is up to the manufacturing par, which goes nowhere near failure or even near the edge of elastic behavior. Where does this number actually fall in terms of stress (load per unit of cross-sectional area), and therefore strain (elongation, the value you are actually concerned with in terms of bending/breaking a bar) on the bar? You have to take a material to and past failure to determine the actual capabilities of said material. It's a little hard to explain mechanics of materials by message board...
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Old 02-19-2013, 10:09 AM   #9
Anjali Patwari
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Re: PSI on Vulcan and/or Hammerhead CrossFit Bar

Quote:
Originally Posted by Eric Huesman View Post

The president of IVANKO, Tom I. Lincir, kind of explains that in this article:

http://www.garageiron.com/How-Strong...rbell_b_8.html (WFS)
Very interesting article!

"Eleiko, which is the finest bar in the world, has a tensile strength of 215,000 psi. The average Olympic bar is made and sold as "1,000 pound test" and usually runs about 130,000 to 150,000 psi. Almost all of them are 130,000 psi."
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