A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Position-Finding
From: Brian Whatcott
Date: 2002 Jun 23, 14:22 -0500
At 07:23 AM 6/23/02, you wrote: >If the clockwork presents low drag the slip of the fish is very low and the >fish moves thru the water like a screw in wood. Thus I suggest the accuracy of >a tafrail log is better than one percent. Unfortunately it doesn't perform so >well in southern waters since it continually fouls with Sargasso weed. > >Don't forget to keep the fish painted black since it looks like a tasty treat >to many of the denizens and at $40 per replacement can seriusly reduce your >beer ration. There is a braided closline for sale that works as well as the >"special" and costly log line sold for the purpose. > >Many paddle wheel logs are defficient at low speeds. The magnetic sensor gives >an impulse whether rotated forward or backwards. Thus whenever the water flow >is from aft to forward the distance traveled is incremented instead of >decremented. To approach the same accuracy as a taffrail log one must >calibrate >for different sea conditions and headings. > >The chip log seems like a good idea if it is streamed regularly but I never >figured out how to reteive it easily at speed due to its drag. > >Walter Guinon >Lincolnville Maine This is just a stray memory trace - of the paradoxical kind that doesn't go away, though essentially valueless. I was in a Midlands supplier's store - probably in Birmingham (UK) and I was looking over the amazing variety of cast brassware (of the kind which was advertized as 'toys') and I saw a taffrail log hanging on a wall - for sale, new - several minidials and pointers (for distance run?) and a speed indicator. Could Walker have been a Midlands company? Did it expire in the last twenty years or so? Brian Whatcott Altus OK Eureka!