Paddle log v gps log?

[Sabre27Admin]

kcalco
United Kingdom
58 Posts

Posted - 21/09/2011 : 00:11:19
Hi

Lets assume the paddle log does not get fouled up.
What are the pros and cons?
Is it better to know your through the water distance than over the ground distance?

I have a paddle wheel log but the through hull is blanked off with a plug,which is exactlly the same as the transducer. How risky is it to pull the plug and slid the transducer into the hole, with the boat in the water (fin keel). I could put an orange box under the keel in the marina as there is only a few inches of water at low tide. Okay an orange box may not be strong enough.

Regards Ken
sabre27
178 Posts

Posted - 21/09/2011 : 09:59:54
Hi Ken.

It all depends on your immediate circumstances, these may vary wildly, so it could be either. You probably like most of us, have both, so let’s address the more problematic one, the paddle wheel log.

In common with a large proportion of sailors, I have the same log system. My default position is to leave the transducer in place. After a period on the mooring, small crustaceans sometimes take up residence in the paddles, temporarily jamming them. If this does not clear within a short time under way I pull out the transducer with one hand and shove in the blank with the other, rather quickly! Then clear the ‘squatters’ at my leisure and carefully, but quickly (taking care not to damage the paddle wheel spindle) reverse the process and clean up the mess.

I will have to do this a number of times during a season. Practice makes perfect, or as near as you can get! When you pull out the transducer or blank, the water makes a determined effort to come in! It so happens that my head floorboard can be stood up vertically in the head door aperture during this procedure, thus keeping most of the ‘incoming’ in the bilge. I have assumed that your log is in the head compartment.

Beware. Corsair sits in soft mud at low water and I, only once, forgot that she was not floating when I removed the transducer for routine maintenance. Oops!


Paul Howard. S27OA Technical Officer.

ianfr
United Kingdom
104 Posts

Posted - 21/09/2011 : 10:05:00
Hi Ken

I don't have a log on Apogee but did on the last boat. I was lucky in that I could remove the whole thing without getting water in the boat. I found the through the water speed was most useful for sail trimming rather than calculating actual speed. Most GPS systems update speed every couple of seconds, and the figure is skewed by lateral movement. A log updates far more quickly, so the effect of a pull on a sheet is pretty quickly apparent.

I may at some point fit a log as the skin fittings are already there and full up with dead seafarer kit.

Regards

Ian

Kind Regards

Ian

kcalco
United Kingdom
58 Posts

Posted - 21/09/2011 : 12:36:28
Hi
Paul
My log is just in front and to the right of the engin. Okay I will have a go when I have enough courage. I think i will have a wooden plug and big hammer beside me just in case thing don't go well.

Just to let you know I have sailed close hauled with 25deg heel and zero weather helm, in fact I can take the autohelm off and it will steer perfectly for 60 seconds (no hand no elast bands) after implementing all the info you gave me some time ago on sail trim. Thankyou

Ian
Yes I can see that it will resond to sail trim quicker, GPS log take a few minutes to work out if its quicker or not.

Many thanks Ken

NPMR
United Kingdom
59 Posts

Posted - 25/09/2011 : 09:57:50
I agree with Ianfr, that a GPS is not useful for gaining knowledge about boat trim as it measures the wrong things.

You need to know if a change of sail trim is effective, so you need the log.

Another thought; on a passage, we keep a paper chart going as well as the (two) GPS. You need the log, 'distance run' for this.

Yes, they clog up but after a while, you get the hang of doing it really fast to keep the inrush of water to a minimum!

Nigel R
HUZZAH

Sunfly
United Kingdom
51 Posts

Posted - 28/09/2011 : 22:25:13 Sunfly's Homepage Edit Reply Reply with Quote View user's IP address Delete Reply
You'll ship a pint or two as you swop - either an amount that's easy to mop up or that isn't a significant change depending on what your bilges normally look like!

I feel compelled to say if you need to shove a tapered bung in, do not whack it with a mallet as you may well split the skin fitting making matters much worse...

The choice between GPS speed and a log... some people prefer to navigate 'manually', and a water log is an important tool in this process. I like to navigate manually because much more rewarding and maybe even fun, and keeps your hand in for when the USA switches of the satelites, or the 12V system fails. Having said that I'm often too lazy and rely on the GPS.


Nothing - absolute nothing half so much worth doing as simply messing about in boats

http://sunflythesabre.wordpress.com