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Author
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Topic: Taffrail log or substitute
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ash13brook
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posted March 30, 2011 04:49 AM
Are there any plans that anyone knows of for the making of a taffrail log?
It seems that any home machinist would be able to manufacture one fairly easily ( with the exception of the spinner, maybe)given a set of plans.
Does anyone know of a suitable MECHANICAL substitute?
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David Burch
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posted March 30, 2011 04:10 PM
i would guess the biggest issue is the clockwork to count the turns.
Periodically you see these used in the range of 500 to 1000 dollars, but that is not bad at all since they cost more than that new and i cannot imagine them waring out. some have been used since early 1900s and many were used in WW2
or there are options. i have seen a rig once with just a J tube you hold in the water and then calibrate it for speed on how high the water rises. should be a fun experiment.
then there are things like these:
http://www.knotstick.com
http://72.230.216.155/Alberg35/Projects/Instruments/SumLog.html
see notes in your other question about our Emergency Nav book and course
the chip log, however, is likely the best bet. we cover it in depth in that book.
From: Starpath, Seattle, WA
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