Compass deviation

[JD-MDR]

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I moved the ignition panel. It wasn't bad the wire harness reached .Compass reading is 73 degrees. Same as my handheld.It was showing 120.The neighbor has 80 degrees. I will figure out how to adjust it. For now I put the panel under the breakers and used the wires for the knot meter for the compass light. I only use the Sounder when I anchor Maybe it will be ok. Also the VHF is over there.

[John Stone]

JD
That seems like a good start. Don’t worry what the neighbors boat compass reads . . . His could be off. It’s only important that your compass is accurate. I’d look hard at moving everything eventually. Also, one thing “the experts” recommend is to twist any wires running past or near the compass. Don’t underestimate the influence of electromagnetic radiation on a compass.

I look forward to hearing how it turns out.

[Jim Davis]

In the VHF, the speaker and microphone have magnets in them. Most likely the chassis inside the radio is steel.

As to adjusting there are several good sources of information. Ritchie publishes fairly easy to follow instructions. You should be able to get it close, then make a deviation table if needed.

[tjr818]

Every aircraft that I have flown has a magnetic compass in addition to all of the fancy electronics, right next to the magnetic compass is a compass deviation chart, a little paper thing about 2" x 3". They usually look similar to this:
http://www.boldmethod.com/images/learn- ... iation.jpg

It is almost impossible to adjust all error out of a magnetic compass aboard any vessel.
Her is a link to a USCG form for the chart.

https://media.defense.gov/2017/Oct/16/2 ... G_2596.PDF

[Steve Laume]

So now you can only start your engine from down below? What if you needed it suddenly while at the helm alone? Will you ever start it from down there and not both to go topside and check for exhaust water flow? Will you need to go back and forth several times to adjust the throttle to the desired RPMs? This just doesn't seem like the right solution to correcting the compass.

I think I would be building a nice protective box for it to be mounted on the mizzen mast. On a tiller boat, a bulkhead mounted compass would work for me. If you are sitting all the way at the back of the cockpit it would be pretty hard to read, especially at night. On the mizzen, you will be able to move to any height that you desire, It will be closer and easier to read. Most importantly, it will be well away from forces that might influence it's accuracy. You will never have to ask a guest to move so you can see it or have an annoying lump on the backrest.

The mizzen just seems like the best place for it, Steve.

[JD-MDR]

It's just tacked there while I decide wha I want to do.Good point. Its only a little stretch further than where it was. Some day I want push button starter and audible slarms. I don't think I need to see it all the time I can hear and smell whenever I sense a problem.. I will soon have auto pilot which I will use always.Personally I don't want any stuff around the mizzen . Space is tight enough already. When I worked on commercial boats it was good practice to start and shut down from the engine room.That way you can check the oil while your there and you can see that everything is OK. It Just a side note. I was at it to. 2 AM moving the radio it was a real pain. I'm going sailing now. I've never tried the Spinnaker or the mizzen staysail. The pole is different I'm not sure how it goes.

[John Stone]

Steve makes a good point, as he often does. Certainly you want to be able to see the compass from your normal steering station, but I assume you have already come to that resolution since the compass is on the bulkhead and you have experience with it in that position.

I don't understand the fascination with having instruments in the cockpit much less engine gauges. In September I spent three days sailing with a friend on his CD 36. The engine ignition and all gauges were below in the saloon near the companionway. It worked fine. Additionally, they were out of the weather thus they suffer no ill effects from long term exposure to rain, salt spray, or a pooped cockpit.

I don't have an inboard in the Far Reach, and seldom have the outboard and use it even less. But if I do install an inboard someday, I would want the instrument panel below deck.

Keep it simple. Reduce clutter. Increase reliability. Be smart and safe. Focus on sailing and seamanship. In the long run, I think such an approach will lead to maximum enjoyment of your boat.

[Neil Gordon]

As a general rule we'd recommend guages over lights and buzzers alone, and for good reason. The same reasons suggest the guages should be visible.

[Steve Kuhar]

Most of our sailing is VFR with probably less than 10% of our time sailing on a compass course. On our 25D we used a surface mount compass mounted on the INSIDE of the bottom companion way drop board. When we need the compass we just put the drop board in backwards. It makes it a little bit clumsy stepping over it to get into the cabin, but it is doable. An additional advantage with an offset companionway is that you can also offset the compass mount on the drop board so that the compass is nearly on the boats centerline when in use. The compass is also inside and out of the weather when the boat is not in use.

All just some food for thought.

Steve Kuhar

[John Stone]

Very clever idea Steve. I like it.

[Nebe]

To get around my compass being off, when i use my navionics app to lay a course, it will shoot a red arrow on the chart. I wander my bow around slowly until my red line is on the way point and immediately look at my compass. With this technique, the compass could be 200° off and it wouldn't matter. ( until my iPhone stops working)

[Neil Gordon]

To get around my compass being off, when i use my navionics app to lay a course, it will shoot a red arrow on the chart. I wander my bow around slowly until my red line is on the way point and immediately look at my compass. With this technique, the compass could be 200° off and it wouldn't matter. ( until my iPhone stops working)

Remember that the course on the app included built in adjustments for leeway and current.

A deviation table remains a good idea. If the deviation on any particular bearing is small enough, you can ignore the table altogether.

[JD-MDR]

Thanks everyone I will keep all these points in mind when I go to finish this. I'm gonna move the sounder then every thing will be on the starboard side. I like the compass right where I have it. What do I need the inclinometer for. I will start to repair the fiberglass. Now I have to focus on new sails. I didn't get a response when I asked about Ullman sails. There is a Ullman loft here. I got Doyle for my previous boat. I really like theirs But their loft is too far down the coast. They don't come this far up. I raised the Spinnaker at the slip It seems like it's not gonna be easy to take down by myself . I did use me 150 genoa. Didnt last long. I think all my sails are 40 yrs old.