walker trailing Log

[Pagetslady]

hi how accurate is a trailing log, i want to use one to calibrate my Raymarine log will the trailing log be accurate enough?
Mike

 

[sarabande]

some discussion here

http://www.ybw.com/forums/archive/index.php/t-337216.html


I would consider using a handheld GPS in conjunction with some trusted tide tables.

 

[johnalison]

A walker log can be subject to the odd error, as when going too slowly of when it picks up a little weed but generally it should be pretty good. I used to use one regularly to calibrate the pathetic old Navico log on our old Sadler. I regarded it as much more reliable than a measured mile in a tideway.

 

[Sarnia]

Thanks for the link, I use a walker on longer trips, bit of nostalgia I expect, but the link suggested that the line should be calibrated length wise to the unit. May be I am missing something, but why does the length effect the reading, the spinner revolves at the same revs at a set speed regardless of cord length, and the revs determine the reading.

 

[sarabande]

the longer the line, the more resistance to rotating, and there may be a function of the angle of the line to the surface of the sea.

 

[VicS]

Instructions for walker log

http://s50.photobucket.com/user/Vic43/library/Walker log