The Sherlock Ohms stories never fail to amaze me. I never would have considered adding a ground strap between the wagon body and axle frame. Engineers -- especially those who submit our Sherlock Ohms stories -- are an amazingly clever bunch.
It was good of the vendor to offer a solution to the customer's modification. Good vendors will help as long as safety is not concerned. As a teen, I was working on an old Chevy loosening a bolt that was too close to the frame to reach with a standard box wrench, so I ground some off of the OD which promptly broke. I then took the Craftsman wrench back to Sears who said that it had been modified, but it should have been tough anyway and gave me a replacement.
That is a very interesting story and great job about troubleshooting a field failure with an uncooperative customer...it is also a great reminder to inquire as to any modifications that a customer may have made that can introduce problems that they are blaming on the original design!
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