Small Compass Q

[Yannis]

Does anybody know a compass which is dash mounted and its diameter is not more than 5-6 cm (2 inches give or take) ? How good can it be ?
Thanx.

[IRGuy]

Yannis...

There are quite a few small compasses in that size range here in the US for vehicles, sold in auto parts stores.. I have one mounted on the dash of my pickup truck. Mine is mounted on a flat foot that is held on the top of the dash with Velcro. I would not think it is accurate enough to navigate a boat with, but for other general, less demanding applications it is fine. They don't cost very much.. if you want I can send you one.. no charge, we can call it an investment in international relations!

I can send you a picture of what I have if you like.. just send me an email and let me know.

Frank Bryson
IRGuy@aol.com

[mike ohlstein]

You could install a fluxgate compass down below, and mount a display anywhere. If you have autopilot, then you already have a fluxgate compass, and could probably tap into it.

[Yannis]

First of all, its a good idea that IRGuy stands for Frank Bryson. It rhimes !!
Second, I thank you for both your info and your offer. I believe we also have those tough-car compasses.

On the other hand, in the Cyclades where I almost always cruise, almost nothing is beyond daily eye view and fogs are, almost as well, unknown.

I wish a compass that will fit in the dash hole of the (removed) tiller dial. It's small and I would like to fill it with a similar compass. I already removed the main compass.

I have 2 other compasses aboard too. One is the GPS's.

[mike ohlstein]

There are also plenty of small compass's made for small planes that dash mount.

[Yannis]

Mike,
What is fluxgate?
Planes, good idea, I have a friend who flies, I'll ask him . Thanx.

PS An autohelm on a Bertram? Where's the fun !

[Tony Meola]

https://www.ritchienavigation.com/resea ... ash-mount/

About like this? Or maybe this.

https://www.ritchienavigation.com/resea ... ash-mount/

https://www.ritchienavigation.com/resea ... ead-mount/

[Navatech]

What is fluxgate?

Fluxgate compasses are "electronic" compasses...

An autohelm on a Bertram? Where's the fun !

When you have to steer for hours on end the fun wears off...

[Yannis]

Tony thank you. More like the first one; the others, although very tempting, don't fit.
Nav, you're right, I had forgotten the very long trips; only temporarily, I believe, due to the long winter...

[Navatech]

More like the first one

The cheapest one I have found on-line...

Contact the seller and see if he'll ship to Greece... If he/she can't be convinced to ship to Greece, let me know and I can help out...

[Tony Meola]

Yannis

Be careful. I am not sure it fluid in it so it is going to rock and roll a lot. Might be hard to read in a sloppy sea.

Also can not be compensated so you would need magnets if it is off.

[Navatech]

Yannis, Tony raises a good point about being liquid filled (dampened)... Personally I wouldn't worry too much about compensation (you don't have a mass of metal on your FB right)...

If you want I can hop over tomorrow to my local West Marine and see if they have this item in stock... Just so that I can see what it looks like in real life...

UPDATE: one of the reviewers here complained that the liquid seeped out of the compass... So, I guess that answers that question...

[Yannis]

Tony and Nav,

Thank you for your advice and consideration.
I was supposed to go myself to the Ritchie importer's store yesterday morning, but stopped instead at Ikea for other chores so I'll just postpone it for next week.
Depending on whether they carry the item, the price etc, I might come back to you.
Until then, I'm preparing for Easter amid rain and some snow; apparently it will clear for Sunday to grill the lamb on the spit...

[Rawleigh]

I have one of these older Ritchie electronic compasses to mount in an existing hole on my bridge that now has an old aircraft fluxgate in it. Looks like Ritchie does not make it anymore though.

http://www.foreandaftmarine.com/128-M2W.htm

[Yannis]

I'm not sure I have ever seen an electronic compass before. I had no idea they existed.
Looks great and, what's even better I suppose, is the accuracy.
But at $200 the small one, it looks like I'll never have it...

What installation does it require? What else?

[Navatech]

What installation does it require? What else?

Basically it needs power... Otherwise there's not much to it... You put the display wherever you want it... The sensor itself is preferably installed centerline and as low as possible in the boat... Waterline height is best... Then you have to connect the sensor to the display...

About what it is and how it works...

I have one of these which you can have for free (shipping on me, donation to the site appreciated)... It was in my boat but unused... The wires had been cut close to the sensor and the boat had been last operated with Garmin equipment... I installed a new Iron Mike (autopilot) that came with its own... If you have a Raymarine GPS you should be able to hook it up... Possibly other MFD's as well...

[Yannis]

Nav you're a wealth of mechanical insight !

Thank you for your offer, but I think this is too complicated for me. A compass plus a sensor plus connections etc, I'm more like " le vieil homme et la mer" type of thing.
Plus, I need a compass that when all electricity (so to speak) fails, it still works. A needle compass.

[Carl]

I need a compass that when all electricity (so to speak) fails, it still works. A needle compass.

Then your going to want a pretty light, buoyant compass, as movement will only be had if your swimming. Boats don't go too far without power.
Unless you just want to know the direction your drifting.



However, I do agree...simple needle that points the way when all else fails is a must for me.

Heading back one afternoon from offshore and sun is behind us...Hey buddy, where we going, I ask. Home! he answers. I don't think so...he tells me GPS says we are right on track. I asked the heading on compass and get due E...ast....oops. Wrong waypoint and a quick 180. Yeah I like those little needles too....even a cheap one points sorta right.

[Navatech]

Nav you're a wealth of mechanical insight !

Google is your friend ;-)

I think this is too complicated for me. A compass plus a sensor plus connections etc

It's really not that complicated... One single multiple strand cable will get the power to the unit and return the signal to the MFD... The connection itself is a simple NMEA 0183 connection...

I need a compass that when all electricity (so to speak) fails, it still works. A needle compass.

We ALL need one of those... And, as long as it ROUGHLY points in the right direction you're good to go... I don't know exactly where you boat but assuming it's the Aegean as long as you're going east or west you should hit land pretty soon... Now, if instead you're going north or south you might need to go for a while till you hit land... Unless you get lucky and hit one of the islands... Of course, if you don't know where you are you might be so unlucky as to actually hit one of the islands...

That happened once to an Israeli naval vessel... ripped the bottom out of the chain locker and the forward compartment... They had to go in reverse all the way to Haifa... Roughly 500 nautical miles... Yeah, they filled the compartment with anything and everything floating they could find... There's a reason the navy uses closed cell foam mattresses... But they were worried the shoring of the 2nd bulkhead wouldn't be enough... And with two major compartments compromised the safety of the vessel would have been questionable... 500 miles at about 5 knots... NOT fun!... But they made it... Without assistance... And the boat was back on duty a couple of months later...

Aside from time there's the problem that if you land on the wrong beach south you might run across a Jihadi with a more or less sharp knife... NOT good!... Just kidding of course... I doubt you carry enough fuel to go that far south... What is it?!... About 350 nautical miles from Athens to North Africa?!... And roughly half that from the south of Crete?!...

[Yannis]

Yeah I like those little needles too....even a cheap one points sorta right.

That's what I thought too; when GPS fails, at least you can return home, or at least towards home.

What is it?!... About 350 nautical miles from Athens to North Africa... And roughly half that from the south of Crete?!...

I believe your numbers are OK, the point is that the occasions in which you're in real need of a compass in the Aegean are limited. In very few instances can you be more than 5-15 n.m. away from land. Which makes it pretty much a "look around and cruise" type of situation.

[Navatech]

In very few instances can you be more than 5-15 n.m. away from land. Which makes it pretty much a "look around and cruise" type of situation.

Look around and cruise is fine... It's the barely underwater "islands" (such as the one the Israeli naval vessel encountered) which would worry me... You really need to know where you are... Having local knowledge makes a difference too... Some things just aren't to be found on the maps... The simple reason that most maps are made for commercial vessels... Us pleasure boaters can go where the commercial vessels can't go... But most map makers don't address those areas...

Luckily with modern GPS and depth sounders data collected by pleasure boaters is being collected and added to the available knowledge ("standard" maps)...