Fouling of Nasa Clipper Log

DennisF

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As per title, every year I find that about half way through the season the Nasa Clipper log gives up the ghost due to things growing in the paddle wheel. Boat is on the Orwell on the East Coast. Is there any compatible antifoul that can be applied, or do I just have to keep scaring the crew by removing it for a clean on the water? ?
 

Rappey

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I rarely got a few weeks out of a paddlewheel log before it stopped..
fitted an analogue speedo with gps and use a trailing log if i want to know speed through water..
 

Birdseye

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I suggest to wean yourself off logs as they all get bunged up with detritus. For a number of years now I have relied on speed over the ground from GPS. Not the same but just as good and it doesn't get bunged up!
My vote too. I only put the log in for long passages or races. In reality the speed you need to know for navigation is the speed over the ground anyway.
 

Sandy

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As per title, every year I find that about half way through the season the Nasa Clipper log gives up the ghost due to things growing in the paddle wheel. Boat is on the Orwell on the East Coast. Is there any compatible antifoul that can be applied, or do I just have to keep scaring the crew by removing it for a clean on the water? ?
Do you not have a blanking plate for use between sails?
 

Kelpie

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Another vote for only putting the paddlewheel in when you are using the boat. It works for us because we generally do one or two long cruises each year, rather than lots of weekends and day-sails. It's worth having if your wind instrument needs it for calculating true vs apparent, and also when you are encountering significant tidal streams. I like to know what is going on around me, and GPS speed doesn't give you as much information.
 

neilf39

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Always had the problem with the NASA log even antifouling it. Now have an airmar dst800 sensor and that has not clogged in 3 years. Paddle shape is different so not so susceptible to critters making a home I reckon. Sensor replaced when I switched to Garmin gear.
 

pvb

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Always had the problem with the NASA log even antifouling it. Now have an airmar dst800 sensor and that has not clogged in 3 years. Paddle shape is different so not so susceptible to critters making a home I reckon. Sensor replaced when I switched to Garmin gear.

Mine's a DST800, but I still antifoul it.
 

mainsail1

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To be honest, I'm not sure which data the stuff uses to compute. But I seem to remember that when the log wasn't working once, the true wind data disappeared.
Yes it would disappear unless you were able to switch over to SOG data. No idea if your kit would let you do that.
 

johnalison

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My true wind display just reverts to apparent when the log isn't working.

I don't know the NASA log but the Navico log in our last boat fouled much more than the Raymarine one we now have. My advice is to learn to deal with cleaning the transducer without fuss, and withdraw it when not in use, and your life will be easier. There is a thread going on about this at the moment in the PBO forum with assorted advice.
 

MikeBz

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Surely speed over the ground data makes true wind info even more accurate?

That depends on whether you consider 'true wind' to be wind-over-the-ground or wind-over-the-water. I would argue that the latter is more useful since it is what the boat sees when it is stationary in the water (not attached to the land), it's what you've actually got to sail with before adding in apparent wind caused by movement through the water.

Imagine there is 5 knots of tide flowing from N to S and a 10 knot (over the ground) Northerly. As far as the water is concerned there is a 5 knot Northerly. If your boat is anchored it will see 10 knots of breeze, but if you up anchor and drift (the starting point for sailing) it will see 5 knots. Of course this gets more complicated since to calculate true wind as wind-over-the-water you need to know both speed and direction of travel through the water - I guess the heading is near enough for the latter but obviously doesn't take into account leeway.

I'll get me coat.
 
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