GPS or Shops log

icarusbop

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Hello:

I have enough space for four instruments on my binnacle.
Currently in order I have, Auto pilot - Speed (via ships log) - depth - wind
I have aquired a GPS display which will interface with all my other instruments, but there is no space for it, so my options are as follows..

  1. Remove the ships log speed and replace with GPS - which will also show (actual) speed
  2. Don;t use the GPS and keep Speed and depth as is
  3. I can change one display to a tri data which will show speed and depth and replace one with the GPS, theoretically giving me all the current instruments I have - the downside to this is my current depth has other indicators available (e.g. a graph of the seabed) but I will lose this extra data if I remove the depth.

I was thinking with a GPS, I might not really need the log and can keep the detailed depth, what does everyone think?
Thanks
 
Without a log how do you know what the tide strength is ?

Good point - I'm quite new to this, so preumably, with GPS and log, I can tell the speed of the tide (actual speed - log speed) - but since I currently don't have access to GPS speed (I have GPS for the radio but no gps display at the moment), right now, I can't use the info to get the strength of the tide (unless I'm missing something).

So going for option 3 above will lose me the Depth graph, but I will gain strength of tide?
 
Good point - I'm quite new to this, so preumably, with GPS and log, I can tell the speed of the tide (actual speed - log speed) - but since I currently don't have access to GPS speed (I have GPS for the radio but no gps display at the moment), right now, I can't use the info to get the strength of the tide (unless I'm missing something).

So going for option 3 above will lose me the Depth graph, but I will gain strength of tide?
Put them all above the main sliding hatch where everybody can see them
 
Tide data seldom needed.

Without a log how do you know what the tide strength is ?
Unless you are doing long passage legs with changes of tide you only need to hve the resultant velocity after tide and leeway have had their effect and this is what the GPS gives you directly. Why these days make it more complicated? You should always have in mind the approx speed and direction of the tide and this is plenty of info to confirm the info the plotter /GPS is givingyou.
As to where to site the instruments, I think it depends who is going to use the GPS(I assume it is a plotter) If it will be mostly the helm fit it at the binnacle but otherwise put it at the bulkhead so the navigator has access without falling over the helms(wo)man.
 
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Personally, I would rank GPS repeater and log as both more important than the windspeed.
I use GPS repeater to check that I'm clearing the next headland etc, as well as a 'progress meter'.
I use the speed log as a sail trim device, it responds more quickly than GPS and is repeatable day to day.

Wind speed is only useful for sail selection, for instance knowing how much jib you will want after heading up at the end of a run.
You can tell if it's windy once you are on the wind, you do not need to look at it constantly.

However, it's good for others on deck to see the instruments, particularly speed, it helps anyone trimming the sails.
So maybe move that one?
 
Assuming Raymarine Instruments and Seatalk bus operating, change Log at binnacle for a multi graphic display from Raymarine. Put the log by the chart table so you can fill the log out with distance covered and log reading etc. The graphic display will give you anything you want, including log for trimming, but you can switch it to almost any read out of GPS/Wind/Log/Depth rolling road or a combination etc etc. You can also get graphical displays of trends. really good for monitoring what is happening to the wind as you get a display of wind speed over the last 12 hours (or whatever you program) Is the wind increasing? A quick button or two and you get the graph of what is happening. Same with lots of other data. A really useful instrument - but not the cheapest.

We have one and wouldn't be without it.
 
Hello:

I have enough space for four instruments on my binnacle.
Currently in order I have, Auto pilot - Speed (via ships log) - depth - wind
I have aquired a GPS display which will interface with all my other instruments, but there is no space for it, so my options are as follows..

  1. Remove the ships log speed and replace with GPS - which will also show (actual) speed
  2. Don;t use the GPS and keep Speed and depth as is
  3. I can change one display to a tri data which will show speed and depth and replace one with the GPS, theoretically giving me all the current instruments I have - the downside to this is my current depth has other indicators available (e.g. a graph of the seabed) but I will lose this extra data if I remove the depth.

I was thinking with a GPS, I might not really need the log and can keep the detailed depth, what does everyone think?
Thanks
3 sounds the best option. Wind speed is easy to live without. Gps sog & cog are really handy in the cockpit IMHO. More so if the log is actually working and not fouled up :)
 
I'd rank wind-speed as the last important. If the boat is horizontal, the sails are flapping wildly, the rudder is stalled & the tea has spilled, it's time to reef......

Knowing the tide strength is IMO important because it can differ significantly to prediction depending on where you are. This can be important even on short passages with lots of tacks. Without the log, you cannot work out the actual tide.

The easiest way to get it all together is exchange the speed & depth for a bi-data display that shows both. then you can have 4 instruments showing 5 things.
 
+1 for wind unimportant. If you are wedded to keeping it though, accurate GPS is on the whole a more useful display than (almost always inaccurate) boatspeed. Just don't do multi-tide passages following the GPS rolling road straight line track.
 
What is your autopilot?
If it's an ST4000 or some of the other Raymarine ones, you can feed NMEA into it from your GPS and display COG and SOG on it.
 
Replace the log with the GPS. Your speed through the water may be interesting but it doesn't tell you if you're going backwards over the ground.

With a nominal cruising speed of 5 knots one has some interest in navigational progress and piloting manoeuvres, both of which can be handled with a GPS and, possibly, reference to a tidal stream chart.
 
I disagree about the windspeed being least important - although I'm more of a sluggish cruiser than a racer, I still like to know what the wind strength is to help decision making, especially when it's strong. Subjective estimates of wind strength are very different depending on wave shape, whether it's cloudy and dark or lovely and sunny etc.

Deciding whether to duck into a safe harbour, plug on in an onshore wind etc. etc. is partly guided keeping an eye on windspeed and gustiness.
 
Our GPS was alongside the chart table and the repeater was on the cockpit vertical side of the coach roof. I disagree that wind speed is unnecessary it's the most important thing letting you know when to reef as the wind picks up.
 
Our GPS was alongside the chart table and the repeater was on the cockpit vertical side of the coach roof. I disagree that wind speed is unnecessary it's the most important thing letting you know when to reef as the wind picks up.

Plenty here will argue that the angle of dangle tells you when to reef, but I'm with you. Windspeed is probably looked at more often that any other instrument chez moi (except the depth when the water is getting very skinny). Also, when getting close to dead downwind I prefer to look at wind direction on the instrument, rather than staring at the masthead and getting a crick in my neck while trying to avoid a gybe.
 
I can't understand reliance on wind speed numbers, isn't how the boat feels more important? Downwind on flat water on a sunny day f6 can be fun and fast but very different to beating into a 4 with some nasty wind over tide waves. Some numbers on their own don't change how the boat wants to be set up.
 
I think it depends how you sail your boat.
How many people, what kind of conditions.
Also whether you are happy to take your time, or whether you frequently find yourself wanting to make best progress.
Also what you are used to.
I've done a lot of dinghy sailing of late, I am now addicted to my digital compass.
If you sail with beginners at all, a speed log is very handy in teaching them the compromise between heading and speed upwind.
Things like depth and windspeed I like to be able to keep an eye on while I'm on deck, but not on the helm.
Hence I'm not too keen on binnacles, except for a chartplotter, which is great for pilotage.
OTOH, binnacle mounted clocks get over the problem of a cockpit full of passengers obscuring the dials.
And talking of clocks, an actual clock is nice to have on deck.
 
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