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Speed required to bend a frame?

My husband recently slid into an ancient VW bug going about 5 mph tops (he was pulling out of a stop sign and the car in front of him suddenly stopped in the intersection)in our tiny Renault Twingo. Now the driver is claiming the frame on his car was bent by the accident, which I cannot imagine. So my question: how fast do you need to be going to bend someone's frame? There was no noticable damage to the bumper on the VW, nor on our little Twingo.


  • edited January 2010

    On April 9, 1971, the agency issued its first passenger car bumper standard -- Federal Motor Vehicle Safety Standard (FMVSS) 215, "Exterior Protection," which became effective on September 1, 1972. This standard called for passenger cars, beginning with model year (MY) 1973, to withstand 5 mph front and 2 mph rear impacts against a perpendicular barrier without damage to certain safety-related components such as headlamps and fuel systems.

    So the answer is, if it met this standard, anything above 2mph could have damaged the frame. If it didn't meet this standard, any speed may have damaged the frame.

    The insurance adjuster will determine if the frame was bent. If you're trying to avoid the mess of going through your insurance, that usually ends up being a mess, too.
  • edited January 2010
    Hit properly at the proper angle by 2,000 pounds of steel it takes very little speed to bend a frame. It's about the density of the energy (in finite elements) and the time involved in the dissipation of the energy (amplitude and duration). And the ability of the particular struck spot to dissipate the energy based on these factors and the angle it was struck at.

    One point. If hubby hit him, it's hubby's fault. Hubby was not allowing enough space between himself and the other vehicle for the conditions. If the frame's bent, and it's confirmed by the adjuster, the blame goes to hubby, not the poor fella in the ancient VW. Hubby needs to learn to leave more space.
  • edited January 2010

    You have to remember that the ancient VW was built using the "latest" 1930s technology.

    In other words, its construction cannot compare to more modern vehicles in either structural rigidity or passenger protection. Then, you have to factor in likely rust damage that may have weakened the structure of that old VW over the decades.

    Put it all together and...yes, it is entirely likely that the 5 mph collision bent the frame of that old VW.
  • edited January 2010
    There is nothing magic about a framed vehicle that makes it inherently stronger than a uni body. In many cases, non framed vehicles may be stronger. Entirely possible especially with one that "ancient". Just the age of the vehicle makes it more susceptible to damage. Older cars can bend frames hitting potholes.
  • edited January 2010
    Neither car HAS a "frame"..They are both just sheet-metal structures, like a beer can..When they get a little rust in them, they fold up very easily. You have insurance, right? Use it!
  • edited January 2010
    Granted, but the floor pan was still referred to as a frame by many vw people, to which axle assemblies were attached as well as body shell. Depends on your what your definition of is, is. It wasn't a box frame in the traditional sense, that's for sure.
  • edited January 2010
    I was not a box frame, but if it bent, the wheels would not track properly and that is a hard problem to fix, esp. on such a retarded construction as that old Vdub. Get an independent evalutation, and send you hubby to driving school. He doesn't have to put the peddle to the metal when pulling away from a stop, certainly not with another car in front of him.
  • edited January 2010
    It is also possible that the damage existed before your husband hit it. The insurance adjuster can determine all the damage done and whether there was existing damage. Your insurance only has to pay for damage due the this accident, not preexisting damage. Since you drive a Renault, you don't live in the USA or Canada. Do you have auto insurance? If so, use it. The insurance adjusters know all about this and can make a quick determination.
  • edited January 2010
    Yeah, they had a cool setup. The floor pan and "frame" were one formed sheetmetal assemblage and the body mounted on it.

    But I wonder if "ancient" can be assumed to mean "air cooled". OP?
  • edited January 2010
    If the claimant stated this at the scene then he is jumping to conclusions. If he was shown at a body shop I would want to see the estimate. Sometimes people hear or see what they want to.
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