SLOW DOWN (He screamed)

[Robin]

Surely a log driven by a paddle wheel gives you speed through the water. Very common on small boats I'd have thought. Perhaps very rare on large ones?

I'm currently researching 45-50ft motor yachts for sale in the USA and very few have speed and distance instruments, even those that had several plotters, radar, satellite weather overlays on the plotters, fish finders and even side scan sonars. I had quite a 'discussion' with one broker who told me it wasn't necessary because the GPS gave speed and distance if waypoints were entered.

 

[DAKA]

Jargon like CPA, STW are lost on me, thank you for not abbreviating

My speed through the water is indeed indicated on the display I refer to as log,
I have several other displays that show speed over the seabed which I refer to as my gps speed.


There have been a few comments suggesting my engines drown out shouts but
its very rare that I hear my engines, occasionally when using high revs in a marina I may hear the sound echo off a building otherwise they are silent on the flybridge at all speeds.(not the same inside).

Fireball possibly has the only real solution and thats to make sure I am out of hearing distance in future and just carry on ignoring the nonsense, there is no way my boat creates a dangerous wash at 6 knots to anyone already surviving a F4-F5.

Thats not in anyway suggesting that the skipper who rigged a side tow in unsuitable conditions didnt perceive a risk and I am now happy to have received his communication and acted on his request, shame he didnt manage 'thank you' to be audible after I slowed down even more.

Just a thought but if anyone finds them selves being uncomfortably overtaken by a bigger boat, I find the best course of action is to slow down and allow them to pass quickly, the worst action is to speed up which may in turn force the overtaking vessel to also increase speed.

 

[gjgm]

[
what a complete salock he was for not towing on a 30 m tow line

Excellent.. as long as there is reference to plenty of rope....You dont own Marlow, do you (not the town)?

 

[MapisM]

Surely a log driven by a paddle wheel gives you speed through the water. Very common on small boats I'd have thought. Perhaps very rare on large ones?

Yep, transducers with paddle wheel are very common, particularly those for transom installation. Which can't be fitted on shaft boats, hence yes, more popular on small-ish boats.
Anyway, the real problem is that any paddle wheel log (also the thru-hull ones) becomes useless after just a few weeks of exposure to marine growth.
And I've yet to find boaters who care to clean the wheel as often as necessary to keep it accurate.
And they aren't very accurate at slow speed anyway.
Otoh, if you, Daka, and/or the other forumites who seemed surprised by what I told - have onboard a doppler log as this one, well, forget what I just said!

 

[MapisM]

Jargon like CPA, STW are lost on me, thank you for not abbreviating

My speed through the water is indeed indicated...

Well, you seem to have grasped the STW abbreviation PDQ...
Out of curiosity, which transducer are you using?
And if it's a paddle wheel one, how often do you clean it?

 

[Deleted User YDKXO]

Anyway, the real problem is that any paddle wheel log (also the thru-hull ones) becomes useless after just a few weeks of exposure to marine growth.
And I've yet to find boaters who care to clean the wheel as often as necessary to keep it accurate.
And they aren't very accurate at slow speed anyway.

All correct but thats what the calibration feature is for. I recalibrate my log several times a season to take account of fouling to make sure its reading as accurately as possible. You never know when all your flashy navigational gizmo screens will go blank leaving you with just the magnetic compass and log to navigate by

 

[DAKA]

Well, you seem to have grasped the STW abbreviation PDQ...
Out of curiosity, which transducer are you using?
And if it's a paddle wheel one, how often do you clean it?

Whisper told me what stw stood for, still thinking about cpa.......

I've had a through hull paddle wheel on my last two boats and only experienced 2 issues......

corniche, hit underwater object in the Tynne, removed it to look while using the provided bung, able to unjam it and use it to get home 200nm ish , I replaced the paddle only but the plunger had also been damaged , I needed to remove it again and sand down the paddle wheel and the housing, no problem after that although I did have to calibrate it (turn sideways without removing).


Current boat paddle wheel played up the first season, after removing it twice and using the provided bung I realized the adjustable paddle wheel was off centre and jamming, once centred it has not been out since but again I had to calibrate it.

I have never had to clear weed from either paddle and used to navigate in 4 inches of duck weed with the corniche.

current log is a raymarine I think
last one VDO

 

[Robin]

Nearly all sailboats have paddlewheel logs. The Raymarine ST50 ST60 ST70 ranges have transducers with flap valves that aid removal afloat for cleaning without letting in much water. We always antifouled ours lightly each year when out of the water and very rarely had to either clean it or recalibrate it. Now we are looking at mobos I find it very strange that so many rely purely on GPS speed, because in any tidal situation the difference could be considerable, and off Yarmouth with the fast tides there especially so. Imagine sticking carefully to the 10kt speed limit in Poole, only to find that with the ebb running at 4kts you were booked and fined for doing 14kts.

 

[DAKA]

Now we are looking at mobos I find it very strange that so many rely purely on GPS speed,

Me too

but then with the cost of fuel new mobos arent really being designed with cruising in mind, comfort in the marina has clearly taken a more important role and to be fair GPS and Radar are probably all you need in the solent.

 

[Robin]

Me too

but then with the cost of fuel new mobos arent really being designed with cruising in mind, comfort in the marina has clearly taken a more important role and to be fair GPS and Radar are probably all you need in the solent.

But we are looking (in the USA) at 20 year old trawlers and motor yachts that normally have every other gizmo fitted, except speed/distance and windspeed/direction. The other thing I find odd because so rarely seen in the USA are bow thrusters, although a very small number do have them and stern thrusters as well. Stabilisers are common however and I suspect much more so than here. It also seems there are far more mobos with all teak yottie style interiors rather than the Sunseeker/Princess/Fairline types although there are of course plenty of those too. They are really complaining about the cost of fuel now, it has reached $3.36 for bulk quantities or about £2.10. That is per US Gallon mind, not per litre....

They are really hot on wash over there and periodically have a blitz on offenders, if it says 'No Wake Zone', you'd better believe that is what they mean!

 

[jfm]

Yep, transducers with paddle wheel are very common, particularly those for transom installation. Which can't be fitted on shaft boats, hence yes, more popular on small-ish boats.
Anyway, the real problem is that any paddle wheel log (also the thru-hull ones) becomes useless after just a few weeks of exposure to marine growth.
And I've yet to find boaters who care to clean the wheel as often as necessary to keep it accurate.
And they aren't very accurate at slow speed anyway.
Otoh, if you, Daka, and/or the other forumites who seemed surprised by what I told - have onboard a doppler log as this one, well, forget what I just said!

Mapis it's drifting the thread a bit but those doppler logs are a joke. 250w, $10,000 and they need AC electricity? The engineers need taking outside and giving a good kicking. There have been non paddle wheel STW transducers avaialbe for a while. Now down to £400 for the Garmin (=Airmar) NMEA2k version. I have one of these. I think they're ultrasonic or something, not sure. But they're very accurate, to 0.1 or so knots (because I compare my STW and SOG in the tideless med, and they're the same)

Um, Daka, CPA is closest point of approach. Hardly cryptic: standard abbreviation on Marpa radars for at least 10 years, maybe lots longer when folks used to do those paper radar plots, and now on all AIS displays. Daka you have still not told us how close you got to the shouting sailboat!

 

[jfm]

...new mobos arent really being designed with cruising in mind...

With respect, and not wishing to have a fight, I think that statement is bollox. There are some awful new boats around, but there are loads of proper long legged cruising boats too

 

[MapisM]

But they're very accurate, to 0.1 or so knots (because I compare my STW and SOG in the tideless med, and they're the same)

At which speed you made such comparison?
Afaik, the most critical conditions are at very low speed, where also GPS numbers on speed and direction become critical.
Anyhow, I did read of those Airmar sensors, and I'm sure they're much better than any wheel.
Otoh, I guess there must be still a gap between them and the stuff I linked, 'cause afaik they aren't IMO compliant.
Does it have features like automatic adjustment for water temperature, and correction for vessel pitching, frinstance?

 

[MapisM]

I recalibrate my log several times a season to take account of fouling to make sure its reading as accurately as possible. You never know when all your flashy navigational gizmo screens will go blank leaving you with just the magnetic compass and log to navigate by

Geez, respect. I only calibrated mine once, after installing it...
And during the season, all I do is a scrub to the sensor while snorkeling around the boat - which seems to work just fine.
Are you sure your aproach is easier/faster?

Re.onboard gizmo packing up, well, what better opportunity to dust off that engraved brass sextant you surely have onboard?
Actually, nowadays I think that having no GPS assistance at all is not a realistic scenario anymore.
Chances are that each crew member has another GPS in his/her mobile phone...

 

[jfm]

Does it have features like automatic adjustment for water temperature, and correction for vessel pitching, frinstance?

Nope! OK, it isn't in the doppler set league but I still think 250W power burn for a doppler is just madness. My boat doesn't pitch, incidentally

It does have an instant calibrate/adjust function though. At anytime you can use the touchscreen and wind its speed up/down, having compared with GPS, and this is very easy to do. It's a pretty nice advance on paddle wheels

I'll do a more careful comparison at 6kts and report back on that

 

[Col]

bored bored bored with the same Sh!t being spouted on both sides of the argument.

That's mainly why I don't bother with these forums much nowdays.

 

[DAKA]

With respect, and not wishing to have a fight, I think that statement is bollox. There are some awful new boats around, but there are loads of proper long legged cruising boats too

I hope you didnt seriously think I was including your boat in that generalisation, somewhere is your 1500 thread you will find at least two of my posts genuinely admiring your magnificently designed and equipped boat, I was of course referring to the new style of boat design which resembles a static caravan , shape of which wasnt previously renown for its sea keeping abilities, amazing what a few bottles of bubbly and an anal advertising budget can do for a boats sea keepng abilities .

ps
I dont fight any more, I just post how I see it in the interests of a balanced view and then let others make their own minds up, honest gov.

 

[DAKA]

Um, Daka, CPA is closest point of approach. Hardly cryptic: standard abbreviation on Marpa radars for at least 10 years, maybe lots longer when folks used to do those paper radar plots, and now on all AIS displays. Daka you have still not told us how close you got to the shouting sailboat!

Now I know what CPA means of course I am happy to respond ,
just outside of spitting range.

 

[DAKA]

Re.onboard gizmo packing up, well, what better opportunity to dust off that engraved brass sextant you surely have onboard?
Actually, nowadays I think that having no GPS assistance at all is not a realistic scenario anymore.
Chances are that each crew member has another GPS in his/her mobile phone...

I have lost GPS twice , I suggest you only need to loose it once in order for you to make a commitment to keep the old cr ap on board including paper charts, maintain a written log every 30 mins while on the move by set egg timer.
Time
course
speed through the water
GPS speed
distance to next waypoint
heading to next waypoint
log distance run


GPS signal vanished once, not available on 3 sets for 40 mins.

Another time on a mates boat off the wash (out of sight of land) his fan belt snapped leaving us without any electrics in seconds (presume other faults as well).
I produced my hand held micrologic which ate batteries as quick as you could put new ones in and we soon had robbed every bit of equipment on board of AAs

A speed log is also a great source of amusement..........

Start a photo shoot with a mate, tell him you are going to slow to 20 knots so he can come past and splash through your wake (as you open up to a teasing speed of 2knots above his max speed)

After a few minutes ask him why he isnt coming past and claim your log reads 20 knots and his must be out

 

[fireball]

Daka you have still not told us how close you got to the shouting sailboat!

Now I know what CPA means of course I am happy to respond ,
just outside of spitting range.

Can you be a little more explicit on where this occured? Just outside Yarmouth covers quite a large area ...
If it was just going into the harbour then there isn't a lot of room.
If it was further out then there is plenty of room - and 'just outside spitting range' to me sounds too close ... after all - how far can you spit?