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  #1  
Old 19th January 2013, 01:17 PM
DaveyB DaveyB is offline
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Default Roll bar height too

After roughly positioning my seats and mocking up position of roll bar my head seems close to the top of it too.Instead of butt welding same size bar to bottom to increase height I thought about boring some sleeves out of bdms bar making them same thickness and getting a good fit round the roll bar and welding on the inside and the outside to give me the extra height. And perhaps making the rb1 plates a bit thicker.
What are people's thoughts?

Thanks
Daveyb
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  #2  
Old 20th January 2013, 12:04 PM
PorkChop PorkChop is offline
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The yardstick I would use is 'would a MSA scrutineer pass it?'

The answer in this case would be a firm no. The roll bar is meant to protect your bonce if the worst happens. By extending it in any way, you're introducing 2 possible failure modes that simply don't need to be there.
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Old 20th January 2013, 08:05 PM
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Davey Davey is offline
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Quote:
Originally Posted by PorkChop View Post
The yardstick I would use is 'would a MSA scrutineer pass it?'

The answer in this case would be a firm no. The roll bar is meant to protect your bonce if the worst happens. By extending it in any way, you're introducing 2 possible failure modes that simply don't need to be there.
Fair point but an MSA scrute is unlikely to pass a roll bar that is not sufficiently above the head of the driver either . Draw a line from the top of roll bar to next structural point forwards, in this case the front frame of the chassis and there is a minimum clearance distance required by MSA/FIA, don't know the clearance off the top of my head (excuse the poor pun), but can look it up later if required.

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Old 20th January 2013, 09:25 PM
PorkChop PorkChop is offline
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Then the answer would be to get a roll bar made up that meets your spec, like I'm doing. The book spec bar wouldn't pass MSA either (no diagonal for starters).
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  #5  
Old 21st January 2013, 06:28 PM
DaveyB DaveyB is offline
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Thanks for the response, great idea about using a piece of string to check out the distance ! I will certainly check that out. I tried using the self timer on the camera positioned straight ahead. Your method will be a lot more accurate. Knowing the actual distance may be helpful too.

Did not really want to have to go down the bespoke route, but looks like I may have to consider a bespoke bar after all, i purchased one through a group buy a while ago and did not even think there would be a problem !

Thanks again
Daveyb
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  #6  
Old 21st January 2013, 06:31 PM
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Tatey Tatey is offline
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I'm 6'5" and had to get a taller roll bar made up, I think it had an extra 100 mm of height, this was to take into account that I'd be wearing a helmet and if I had to use the roll bar then I'd be upside down and hanging out of the harness.
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  #7  
Old 21st January 2013, 06:37 PM
DaveyB DaveyB is offline
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From my rough calculations thats about how much extra I need to add.
Did you basically add 100mm on to the book roll bar example. And it still fits ok or did you have to change angles as well?

Daveyb
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