Sea Kayak Navigation: Plotting Your Position With A Compass

chodups

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I'm stealing that!

Yeah Philip is very clever in so many ways. Particularly with words and I have stolen from him before. "Paddling in green water up to my elbows" comes to mind as one of my larcenies.

Thank you, Philip for the article and another Philipism for me to kype. "Unlost".......yeah that's the ticket.........
 

mick_allen

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Hey Philip or anyone . . . are there really flimsy, almost throwaway type cheap, cheap, cheap, douglas type protractors that you could simply tuck one away in every chart or map? There's no movable parts so thin poly or plastic. Hole not even necessary.

Hmm, maybe a thin plastic that can go thru a printer would work?
 

red kite

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Hey Philip or anyone . . . are there really flimsy, almost throwaway type cheap, cheap, cheap, douglas type protractors that you could simply tuck one away in every chart or map? There's no movable parts so thin poly or plastic. Hole not even necessary.

Hmm, maybe a thin plastic that can go thru a printer would work?
I seem to remember clear decal compass charts at Binnacle or similar. Cheap? Not really.
Edit: These are what I was thinking of.

In terms of printing your own: Tried this? ;-) (I'm sure they are available cheaper elsewhere...)
 
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mick_allen

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yah, a few of those sheets would be fine, I'll check them out next time in an office store.
This is a Douglas protractor example that I'm referring to. It's not an exact example but good enough for basics: [this is a png file so should be a transparency in some printers]

DouglasProtractor2.png



using Philips Nav 1 from his blog, you set it on the map with the centre on your start, orthogonals in line with the map grids [one method], and read off the true bearing to the next waypt, or subtract the variance from that bearing to get a compass bearing. I like the idea of having a few of these as they'd lay flat and compact in a chart case or holder [you'd need one handy to move around over the chart in the case, of course], and have the more bulky compass elsewhere on boat, in hand, or on skirt.
 

kayakwriter

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I buy the protractors by the dozen or so from Flight City (which happens to be on my route from home to Jericho Beach Kayak.) At $2.95 each, I can afford to put one in every chart bag, and to give them away to friends. They are a thin and flexible plastic - slightly thicker than the page protectors you'd use in a 3-ring binder. They don't come with the centre string - that's a custom mod (as I think the kids are calling it these days) I do that myself with a small drill bit and rot-proof synthetic cord.
 

red kite

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really flimsy, almost throwaway type cheap, cheap, cheap, [...] protractors

I guess we have a terminology mix up here, Mick.
The part above is what I reacted to...

I've used the type you both are linking to for pretty much my entire paddling career, I would NOT call them flimsy. In fact most of them seem to be printed on PETG, so nearly indestructable, there are polycarbonate variations whch are slightly more brittle. Nor did I consider them cheap cheap cheap (I think for the first one I paid something like $6 retail way back when, I've seen some fancy ones last year at $20 or so - the price on the ones Kayakwriter is linking to is likely the best deal I've ever seen.)
 

mick_allen

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Yah, I like the round protractor approach: more compass intuitive and if string used, less hangup at corners as there ain't any.
The other aspect with printing is that one can accommodate for an average [yearly or so, say] variation in the setup. For example a quick overview shows that a 16deg 20min 'average' might be ok and as quick chart 'on the go' use probably is to a degree or a few something like this could be easily printed up for a few yrs use and then modify:
CompassProtractorModified.png


the internal grid divisions make no sense at this non-scale, so disregard.
 

red kite

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Yah, I like the round protractor approach: more compass intuitive and if string used, less hangup at corners as there ain't any.
The other aspect with printing is that one can accommodate for an average [yearly or so, say] variation in the setup. For example a quick overview shows that a 16deg 20min 'average' might be ok and as quick chart 'on the go' use probably is to a degree or a few something like this could be easily printed up for a few yrs use and then modify:
View attachment 13393

the internal grid divisions make no sense at this non-scale, so disregard.

The only caveat I see with the round version: If I want to plot a course with a line drawn directly on the chart during the trip (say in camp planning for the next day's leg that might deviate somewhat from the big picture trip plan due to weather) - I use the straght edge of the square cockpit plotter for that.
 
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mick_allen

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If you print it there's no restriction on how you cut it out: could have curved, straight or even zigzag sides - at least that would simulate how I actually paddle even when I do want to go straight!

Anyway here's a cleaned up version without extraneous divisions - and with an 'average' lower BC variance noted.

CompassProtractorVaried&Rev.png


and if you can get a printable acrylic page for 69cents like red kite shows above, here's an 8.5 x 11 format of 4 copies in png form - I guess one each for under 20cents.

Anyway, an idea.
 

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Roy222

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It all sounds good in a calm sea but hoe do you mange this navigation in rough water?

When I was a kid and fished Lake Champlaine with my father he would do something like what you describe.
He would line two two object on shore, like a telephone pole and a barn silo and then follow that line until two other objects lined up.
He keep a little book with all the fishing spot alignments.
 
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