Log transducer - best place?

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SteveN
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Log transducer - best place?

Post by SteveN »

Our existing B&G propellor-type log transducer is going in the bin at seasons's end as it gets fouled by weed etc. again and again. Would there be a better place to site a new paddlewheel unit on this hull form, rather than the existing - marked by the white dots?

The current log under-reads badly when heeled on one tack - can't recall which one. I'm not against filling the existing hole and cutting a new one if the situation can be improved. I don't really want to fit 2 transducers + mercury switch etc.

I guess that there isn't really anywhere better. Any thoughts?

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Silkie
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Post by Silkie »

I would have thought the flow might be quite turbulent so close to the leading edge and it might make a difference which tack you are on.

Can't say that I've paid much attention to where others site their paddlewheels but Silkie's is much further back, just aft of max beam IIRC, at a similar height proportionally.

AFAIK all paddlewheels suffer from fouling. Moving it into deeper shade should help but won't solve the problem completely. Do you antifoul it?
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SteveN
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Post by SteveN »

Thanks Silkie. I think I may look to moving it further back, though the tankage under the sole may limit me.

No I don't a/f it. It's not fouling from marine growth that is the problem. rather that it catches every little bit of floating weed out there. Pumping the transducer up and down to free it is a regular occupation. I hope that a paddlewheel will be better in that respect.
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Telo
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Post by Telo »

SteveN wrote: I hope that a paddlewheel will be better in that respect.
Hope you're lucky with it, but, our paddle wheel log stops and starts fairly often. They're all sensitive and prone to interference from weed, grit, molluscs etc imho.
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DaveS
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Sticky log transducers

Post by DaveS »

I would agree, my paddlewheel often stops - particularly if the boat has been unused for a few weeks. I can usually get it going while avoiding getting water in by slacking off the lock nut by a turn or two then turning it round 180 degrees and back again. This is one job that's much easier with two on board: one to watch the display and one to twiddle.
SteveN
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Post by SteveN »

Ah well, I'll give it a try because I've already ordered it!

I don't remember the paddlewheel log on previous boats being anywhere near as bad as this one which not only stops, but also goes slow as if there's just a little bit of weed on the propellor slowing it down. Shame because I do like it's analogue display.
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sahona
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Post by sahona »

Could it be the log impellor design? My ST takes a coat of antifoul and works very well, only occasionally needing a knot or two to get it kickstarted after a while lying idle. Like others, it's mounted under the turn of the bilge, rather than up front.
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Rowana
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Post by Rowana »

Mine is also fitted mutch further aft, but it only works for a few weeks after launching, then gets gunged up and stops working. It then works intermittently from then on. I don't feel like pulling it out to clean it and having a effin' great hole in the bottom of the boat, so I just ignore it.

Do you find it useful, and for what purpose?

The GPS gives me SOG and TTG, which is far more use to me I find.
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SteveN
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Post by SteveN »

Could it be the log impellor design?

Yes. I think so - the existing one is like a wee saildrive leg stuck out there ready to catch all the weed.
Anyway I now have the new one, a Navman 3100, ready to fit over the winter, so I'll see how it goes..

Do you find it useful, and for what purpose?

Yes very. For seeing how fast we're going..? It's what logs are for you know.
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sahona
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Post by sahona »

Rowana wrote: Do you find it useful, and for what purpose?

The GPS gives me SOG and TTG, which is far more use to me I find.
I continually monitor SOG Vs Boatspeed to keep an eye on tides and see if I'm in an eddy or knot. Very useful in N.E. Irish waters and sometimes out West.
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Rowana
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Post by Rowana »

SteveN wrote:
Do you find it useful, and for what purpose?

Yes very. For seeing how fast we're going..? It's what logs are for you know.
I know it's what logs are for, but personally I'm more interested in SOG, which gives me an idea as to when I'm going to arrive at some place, get tied up and the kettle on.
sahona wrote: I continually monitor SOG Vs Boatspeed to keep an eye on tides and see if I'm in an eddy or knot. Very useful in N.E. Irish waters and sometimes out West
I just look up the tide tables and I then know whether the tide is going north or south, and can time my departure from Peterhead to suit. If I'm just going out for a wee bit of a sail, I know which direction I'm going to be pushed. Other than that, I'm not too bothered
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sahona
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Post by sahona »

Assume there aren't eddies/backwaters to consider on the northeast coast .
I recon 100 yards inshore/offshore can make all the difference at times and that tidal predictions are just that, - "predictions"
It's what is actually happening at the time that matters.
Just an opinion, off-course.
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Rowana
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Post by Rowana »

You're probably correct, but I'm not bothered to that extent.

The tide is generally going north or south off Peterhead, and depending on which way I'm going, I try to get the relevant "shove". If I miss the tide, then so be it. I'm out there to relax, so just take what comes.

I've enough stress in my life without bothering about an odd half knot here or there.
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