Sunday, September 12, 2021

DRS Failure

 In the spring of 1991, I was tasked with a regulatory compliance audit of the US Petroleum reserve in  Bakersfield, California. Mostly it was walking around a huge petroleum pumping facility looking for leaks and taking detailed notes. By May, Bakersfield was warming up weather-wise, and I mentioned the fact to my boss in SF.  He said, "I will take care of that", and handed me a one-way ticket to Saudi Arabia. A week later, I was shaking hands with Red Adair's team at the kick-off BBQ.  There was heat, smoke, oil well fires, and crude oil everywhere.

Since then, I have not complained about the heat in California. This summer has been warm and sunny, and I did my spinning outside. 

Anyway, spinning bobbins and flyer whorls I had turned from wood, have contracted and changed my DRS ratios. Often the contraction is only a fraction of a millimeter, but that is enough to affect inserted twist per inch.  

It was a failure, but not a sudden catastrophic failure. Whorl combinations that should have yielded 12 tpi actually produced 17 tpi. Whorl combinations that should have produced 17 tpi, actually spun at more than 20. What should have been 24 tpi was - zero tpi.  (Higher tpi is produced by the whorls being closer to the same diameter, but when they are the same diameter, then tpi is zero.) (Wind on twist with no takeup  a => break-off no use in holding fine singles together.)  That is when I sat up, took notice, and got out the calipers, and started measuring.  

The wheel is not dead, it does not have heatstroke, it just needs a little water.  

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