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Old 03-10-2011, 12:56   #16
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Re: Replace Compass at Helm with GPS

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I know that some people will be horrified at the idea but I am just wondering if it really is so bad an idea.....
You've got that right. Count me as one of the horrified people who thinks it's a bad idea.

You might want to think about resale for a moment. If, as a prospective buyer, I were to board a boat where the owner had ripped out two fine compasses in order to accomplish whatever it is you're trying to accomplish, I'd turn right around and walk the other way, convinced that the original owner was a lunatic.
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Old 03-10-2011, 13:16   #17
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Re: Replace Compass at Helm with GPS

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You've got that right. Count me as one of the horrified people who thinks it's a bad idea.

You might want to think about resale for a moment. If, as a prospective buyer, I were to board a boat where the owner had ripped out two fine compasses in order to accomplish whatever it is you're trying to accomplish, I'd turn right around and walk the other way, convinced that the original owner was a lunatic.

I guess it depends on how big the chart plotter is, too. I just have a little 441s. A friend made a mount for the chart plotter over the compass. He twisted the wires, which prevents the electrical current from throwing the compass off.

I would mention that the chartplotter compass reading and the old fashioned compass reading are always several degrees apart.
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Old 03-10-2011, 13:31   #18
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Re: Replace Compass at Helm with GPS

To me the idea is totally horrifying. As if someone proposed painting over all the windows of his car and replacing with an LCD screen.

How do you orient yourself if you don't look at your compass? Don't you keep an eye on the compass? How do you know where you're going?

To me it is THE fundamental instrument on board. Looking at the compass is like looking out the windshield of my car. I would be totally lost without it, but I suppose others may sail differently.
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Old 03-10-2011, 13:32   #19
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Re: Replace Compass at Helm with GPS

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You've got that right. Count me as one of the horrified people who thinks it's a bad idea.

You might want to think about resale for a moment. If, as a prospective buyer, I were to board a boat where the owner had ripped out two fine compasses in order to accomplish whatever it is you're trying to accomplish, I'd turn right around and walk the other way, convinced that the original owner was a lunatic.
LOL!

+1
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Old 03-10-2011, 13:41   #20
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Re: Replace Compass at Helm with GPS

You might want to check the legal requirements for the country in which your boat is registered. In Canada a magnetic compass is a requirement.
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Old 03-10-2011, 13:51   #21
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Re: Replace Compass at Helm with GPS

A compass gives a steady reading but the GPS is "updated" & is not as useful when sea gets up, sun does not get on the display on a compass. Keep the compasses.
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Old 03-10-2011, 14:40   #22
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Re: Replace Compass at Helm with GPS

I think when this "type" of question comes up to do something the old way or go with the new we have to ask if we are doing it the old way just because of tradition or because it is dependable.

The new technologies add a lot of features and ease of use but with that convenience comes increased complexity, steeper learning curves and arguably greater potential for equipment failure. Conversely, the old technologies typically are simpler to use but in some ways require more knowledge and effort by the user. Each technology has it's good and bad points and when working together can often fill-in the shortcomings of the other.

A common thread in this discussion is keeping redundant systems that can work when others fail. I think the key to success with redundant systems is that we need to also maintain the skills to use those systems. So steering a bearing on a compass course is just as important as steering by a plotter display.

Where I sail, there are places where magnetic disturbances makes a compass unreliable but I have also seen the GPS lose satellite locks for no apparent reason.

On a personal note, I force myself to maintain a paper log and chart in addition to setting routes on the plotter. It takes a lot more time but I can often find something on paper that isn't in the software or visa versa.
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Old 03-10-2011, 15:10   #23
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Re: Replace Compass at Helm with GPS

As I mentioned, I am not thinking of going "compass free"

My thought is really just to move my two compasses from the primary "navigation position" and either placing one centrally on the table or using two smaller compasses set closer to the rail.
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Old 03-10-2011, 15:25   #24
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Re: Replace Compass at Helm with GPS

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Originally Posted by ADMPRTR View Post
I think when this "type" of question comes up to do something the old way or go with the new we have to ask if we are doing it the old way just because of tradition or because it is dependable.

The new technologies add a lot of features and ease of use but with that convenience comes increased complexity, steeper learning curves and arguably greater potential for equipment failure. Conversely, the old technologies typically are simpler to use but in some ways require more knowledge and effort by the user. Each technology has it's good and bad points and when working together can often fill-in the shortcomings of the other.

A common thread in this discussion is keeping redundant systems that can work when others fail. I think the key to success with redundant systems is that we need to also maintain the skills to use those systems. So steering a bearing on a compass course is just as important as steering by a plotter display.

Where I sail, there are places where magnetic disturbances makes a compass unreliable but I have also seen the GPS lose satellite locks for no apparent reason.

On a personal note, I force myself to maintain a paper log and chart in addition to setting routes on the plotter. It takes a lot more time but I can often find something on paper that isn't in the software or visa versa.
I don't think a compass is easier unless you came up using that method before chart plotters or sailed a long time in unknown waters without one.

I think there's no doubt that a chartplotter is a valuable tool, but having been on a boat when the chartplotter failed I know that knowing other ways to navigate is crucial.
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Old 03-10-2011, 15:34   #25
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Re: Replace Compass at Helm with GPS

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As I mentioned, I am not thinking of going "compass free"

My thought is really just to move my two compasses from the primary "navigation position" and either placing one centrally on the table or using two smaller compasses set closer to the rail.
Ya, that's a good idea (sorry for the misunderstanding).

The only potential issue that I see is that the parallax for the compass will be out by the angle that you are in relation to it.

For example, if you are positioned at 10 degrees off the centre then when you are on the starboard side you will need to subtract the compass bearing (i.e. 0 degrees becomes 350) and visa versa for the port heading (0 becomes 10 degrees) (or is it the other way around ). It might get confusing, especially if you have to take into account variation and deviation.
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Old 03-10-2011, 15:39   #26
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Quote:
Originally Posted by Dockhead
To me the idea is totally horrifying. As if someone proposed painting over all the windows of his car and replacing with an LCD screen.

How do you orient yourself if you don't look at your compass? Don't you keep an eye on the compass? How do you know where you're going?

To me it is THE fundamental instrument on board. Looking at the compass is like looking out the windshield of my car. I would be totally lost without it, but I suppose others may sail differently.
A fluxgate reading fed to a chartplotter and displayed is a compass. It works like any other compass. That way you know what way you're going.
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Old 03-10-2011, 15:44   #27
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Re: Replace Compass at Helm with GPS

Hey guys,

Let's not over-worry this issue! Remember... in many (most?) tiller steered boats the compass(es) are mounted on the bulkhead at the forward end of the cockpit in much the same manner as suggested here. Works with them, will work in Hoppy's case, so what's the big deal?

He's NOT abandoning the magnetic compass, just moving it to a new location.

Don't think I would do this, but see no real reason that he shouldn't do it if he wants.

Cheers,

Jim
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Old 03-10-2011, 15:51   #28
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Re: Replace Compass at Helm with GPS

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I don't think a compass is easier unless you came up using that method before chart plotters or sailed a long time in unknown waters without one.
I agree but I am thinking of someone who has not seen either.

I guess what I meant is that the technology of a compass is simpler and you don't need any special skills to look at it (after all, it is just numbers spinning past a mark). However, to understand and act properly on a compass requires special knowledge and skills.

Compare this to a chartplotter. You have to turn it on, know how to use the toggle to set a course, know to press the button that sets your current location, know how to read the display etc. Then you also need that special knowledge on how to use it properly.

As technology, the initial barrier to entry is more difficult with a GPS compared to a compass but a compass needs more special knowledge to use it properly. Once you learn the basics, however, a GPS is probably easier to use which is why it is so popular.

Does that explain it better?
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Old 03-10-2011, 16:16   #29
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Quote:
Originally Posted by ADMPRTR
I agree but I am thinking of someone who has not seen either.

I guess what I meant is that the technology of a compass is simpler and you don't need any special skills to look at it (after all, it is just numbers spinning past a mark). However, to understand and act properly on a compass requires special knowledge and skills.

Compare this to a chartplotter. You have to turn it on, know how to use the toggle to set a course, know to press the button that sets your current location, know how to read the display etc. Then you also need that special knowledge on how to use it properly.

As technology, the initial barrier to entry is more difficult with a GPS compared to a compass but a compass needs more special knowledge to use it properly. Once you learn the basics, however, a GPS is probably easier to use which is why it is so popular.

Does that explain it better?
Not really IMHO. A simple gps is very easy to use it provides course in simple numbers what could be easier. Whereas a compass is actually a complex instrument requiring careful and professional calibration and manual accounting for errors. As a result most modern compasses are the least accurate of all devices on board. ( then there's steel vessels )

There is much merit in the OPs suggestion.
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Old 03-10-2011, 17:33   #30
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Re: Replace Compass at Helm with GPS

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Hey guys,

Let's not over-worry this issue! Remember... in many (most?) tiller steered boats the compass(es) are mounted on the bulkhead at the forward end of the cockpit in much the same manner as suggested here. Works with them, will work in Hoppy's case, so what's the big deal?

He's NOT abandoning the magnetic compass, just moving it to a new location.

Don't think I would do this, but see no real reason that he shouldn't do it if he wants.

Cheers,

Jim
Having had a tiller boat and now a wheel boat, it's not a problem with a tiller because you sit further forward. I have a friend with a tiller boat, and he has his 441 mounted inside the companion on an arm that swings out. He can see it from where he sits. But on my bigger boat, and sitting at the back end, I wouldn't be able to read it from there.

A compass is easier to read, though, and if it's backup, I want my primary source of information in front of me where I can read it easily.
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