yes, 1/8"
Seb's Goblin #454 (2008 SS/TC donor) - Registered
- Thread starter Sebnuts
- Start date
Desert Sasqwatch
Goblin Guru
Impact stop at 30 mph - with 1 foot of impact compression - yields about 30gs (more or less and based on a 'non-stretch' retaining system). At 60 mph - with 1 foot of impact compression - yields about 120gs (these are instantaneous gs that last less than 0.1 sec). If you multiply your weight by the g-force will yield the estimated impact force that can be experienced by the human body. So a 200lb person will have 6000 lb of force at 30 mph and 24,000 lb at 60 mph. Yep, that's correct - the laws of motion play into this where doubling the speed quadruples the kinetic force.
Studies have shown that a human can survive a 100g instantaneous impact, most times, and survive. This number is dependent upon a lot of factors of the impact and the force contact made play heavily into the amount of force that is considered survivable. Keep in mind all of this discussion is for a single impact 'point' - which in the case of a vehicle would be a single seatbelt strap (with the stock donor seatbelts). The impact force is spread over the contact face of the seatbelt strap (lets 2X18 inches or 36 sq.in) so the 'felt' impact is lessened (still hurts at best). Since we typically use harnesses in our Goblins with two straps, the force is split over the two impact 'points' (for most situations) which helps make a greater impact force more survivable (within reason).
So @Gtstorey is correct that the 1/8 inch brackets - assuming 36,000 psi yield strength - will bend for certain and most likely yield at the welds (since they typically have roughly 1/2 the yield strength) and the mount will separate. Having thicker mounting points, at least 1/4 inch plate, are much more robust and can provide better impact safety based on the yield strength, configuration, and how good the welds are.
Just stuff to think about - we all want to be safe and arrive back home in one piece!
Studies have shown that a human can survive a 100g instantaneous impact, most times, and survive. This number is dependent upon a lot of factors of the impact and the force contact made play heavily into the amount of force that is considered survivable. Keep in mind all of this discussion is for a single impact 'point' - which in the case of a vehicle would be a single seatbelt strap (with the stock donor seatbelts). The impact force is spread over the contact face of the seatbelt strap (lets 2X18 inches or 36 sq.in) so the 'felt' impact is lessened (still hurts at best). Since we typically use harnesses in our Goblins with two straps, the force is split over the two impact 'points' (for most situations) which helps make a greater impact force more survivable (within reason).
So @Gtstorey is correct that the 1/8 inch brackets - assuming 36,000 psi yield strength - will bend for certain and most likely yield at the welds (since they typically have roughly 1/2 the yield strength) and the mount will separate. Having thicker mounting points, at least 1/4 inch plate, are much more robust and can provide better impact safety based on the yield strength, configuration, and how good the welds are.
Just stuff to think about - we all want to be safe and arrive back home in one piece!
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Typically, the best way to install a racing harness is to wrap around a tube. If it is at the correct location.
comegetjoe
Goblin Guru
Joe, are these all custom or are there shared plans?
I would be curious to see the calculations on that but it's probably ok with a decent wall thickness. Is that an oval tube or is the picture distorted?
Joebob
Goblin Guru
You can see how I did it in my build log. All the bolting just locates the bar as in an accident, it will just push against the 3 roll bar tubes which is the strongest part of the chassis.
It's cut at an angle to match the roll hoop, that's why it looks like an oval.
This is most likely what I'll end up doing.
Desert Sasqwatch
Goblin Guru
Slider alignment, not perfectly parallel if sliders are too stiff. Loosen mounting bolts on both sides front and back, except one corner leave tight(ish). Pull (push) the seat to that corner, tighten the opposite side bolt. Push (pull) the seat into the other direction of travel and tighten the other bolts - making sure all the bolts on all corners are now tight. The seat should now have parallel sliders.
Yes it is! Too bad I got it before the group buy happened, I would have rather had it in 1/4". The struts stiffened it up pretty good anyway.That sure is a fine looking splitter
RobC76
Well-Known Member
Do you still have this plate laying around. Wondered you would lend it to me if I PayPal you for shipping and ship it back? I have a magnetic broach / drill on hand.
Thanks