Deviation card /table?

[Cruisingdad]

I give up. Which button is that on my GPS?

- CD

[BlueWaterMD]

I just daysail and weekend in protected waters. I barely even use my compass.

[SimonV]

Compass I have two of those, the one in the binoks needs a shake to work and the one at the helm is currently held in place with duct tape

[Maine Sail]

Originally Posted by erps

Do you find that the deviation card changes much between your two season checks?

Yes it sometimes does but it is usually due to changes I've made in the cockpit. Also it is important to calibrate your compass to how you usually sail. For me I always have my plotter, depth and AP on. I actually have two deviations cards, an electronics on card and an electronics off card..

[Maine Sail]

Originally Posted by AdamLein

Maine, I appreciate the need for a proper deviation card in lots of situations, but I also suspect there are many sailors who are almost never in such situations. Day sailors in inland waters who never go out when there's a potential for fog, and carry a GPS... they've (we've) pretty much got it covered.
.

You're in BC. The last time I sailed up in that area I found the fog banks to appear just as they do in Maine from out of nowhere.

7:00 am beautiful crisp blue sky day
8:00 am NOAA confirms beautiful high pressure weather
9:00 am Sailing out of the Fox Isle Thorofare we see this

By 9:20 we were in pea soup for the next 5 hours.... I guess it depends where you sail. In Maine if you don't take navigation seriously you can get into big trouble!!

[npronpro]

If you are going to stay in the same area - like Gulf coast of Florida, or the Bahamas - can you adjust your compass to "true" and then have it synched up with your GPS?

Rleated qustion - can you 'swing' the compass, moving to each heading using the GPS and adjust the compass; and then make a deviation chart?

[johnferrell]

You can use the GPS to swing the compass but you need to account for the local magnetic variation by setting your GPS to magnetic. If it only displays true heading you need to steer for the magnetic heading by adding or subtracting the magnetic variation. If west mag var add to the true heading and subtract if it is east mag var. i.e if you are trying to steer magnetic 0 and your mag var is 10 west you would sail 350 on the GPS. Adjsutments should be made at 90 then 180 then half of the the error at 270 and 0. then swing every thirty degree and record the differnce between your magnetic heading and the heading on the compass--this would be your deviation.

[CaptainForce]

We used to cruise over to the Bahamas before the time of GPS with dead rekoning and a RDF. I had made a deviation card, but stopped using it and instead I would take a pelorus to the bow and call out a mark for the helmsman to note the heading on the binnacle compass. I know there could be some cause for deviation at the bow for some vessels, but I had negligible effects on my boat and this plan always gave us a course that was successful. 'take care and joy, Aythya crew

[sahara]

I keep my boat at a well known boatyard in SW Harbor, Maine. Last year I had new electronics installed at the helm, and when I got on board for the first time in the spring, there was a new deviation card sitting on the nav station. I never have to ask them for this, they just do as part of the routine of properly preparing a boat for cruising. IMO, their reputation for excellence is well deserved.

[pukeslip]

I go wherever the wind takes me. Part of the joy in sailing is that I can leave time on shore, along with the rest of life's troubles. I always find my way back home, with or without an accurate compass.