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Navigation/Charting/Plotting Tools?

19K views 46 replies 14 participants last post by  Boasun 
#1 ·
I've been wondering about what tools I'll need at the nav station. Two I can think of right off: A pair of dividers and either a parallel rule (I think it's called?) or a pair of triangles. Those two will allow me to determine distance and bearing, correct? Watching a Garmin instructional video, there's a guy using a clear plastic, rectangular thing with a half-circle in the middle and all kinds of graduations all over. What's that? Looks like something else I should probably have? (And learn how to use ;)) Anything else, besides soft lead pencils (what hardness works best?), sharpener and erasers? And charts, of course :D If I choose to use a mechanical pencil, what thickness works best?

(This is just the Great Lakes I'll be navigating, so I think I can forgo the expense and learning curve of a sextant and celestial navigation for the nonce.)

TIA,
Jim
 
#2 · (Edited)
SEMIJim-

I'd recommend dividers-the kind that you can open and close with one hand;



a GPS Plotter instead of parallel rules or triangles, which moves up and down the chart without moving laterally.



A protractor is a good idea.



Or a Chart Plotter, if you want to have one item that combines the protractor and the parallel rules.



As for pencils... I would highly recommend using a fairly soft lead, like a 2B, as it will leave darker marks on the chart and is softer so will not damage the chart paper as much as harder leads might. A good gum rubber eraser is also highly recommended. If you use a mechanical pencil, go with either .5 or .7 mm lead, anything larger is going to be hard to mark the chart precisely, and anything smaller is hard to see.

A few other things I've found useful.

1) Post-It flags... are good for keeping track of your position on the chart, without having to constantly mark and erase the chart.

2) A mylar or vellum overlay that is large enough to cover the chart can go a long way to helping you mark the chart without damaging it.

3) A large clear plastic envelope or case can serve the same purpose and serve to protect the charts from spray when used in the cockpit.

4) If you use the clear overlays, a grease pencil is a good way to mark the charts for dangers... since it is very, very, obvious.
 
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#3 ·
I use a set of dividers (I like the ones that have the option of inserting a pencil lead into one of the arms--Weems and Plath makes a good one) and a parallel rule. Along with a mechanical pencil and a good eraser, these tools have served most of my navigational needs. There are a few cases where a triangle protractor comes in handy, but I rarely use it.

Regards,

Leff
 
#4 ·
SD,

The GPS Plotter is a parallel rule, is it not? (Albeit a very nice one :).)

Where's a good place to get dividers like those?

Any protractor, or something special? (And what, precisely, do you use it for?)

I really gotta make a navigation book choice...

Thanks,
Jim
 
#5 ·
leffklm said:
I use a set of dividers (I like the ones that have the option of inserting a pencil lead into one of the arms--Weems and Plath makes a good one)
I briefly tried to find dividers at the Weems & Plath site. Ironically, I found their site difficult to navigate! Perhaps I need to download their catalogue?

leffklm said:
and a parallel rule. Along with a mechanical pencil and a good eraser, these tools have served most of my navigational needs. There are a few cases where a triangle protractor comes in handy, but I rarely use it.
Thanks, Leff. Do you have a suggestion for lead hardness and, since you use a mechanical pencil (I've always preferred them) thickness?

Jim
 
#6 ·
Jim-

I'd recommend The Boater's Bowditch as a good book for you to get on navigation. It is a more readable, re-written and edited version of Bowditch's, designed for the small craft navigator specifically.

The GPS Plotter is a parallel rule, but it moves perpendicular to the long axis, rather than at an angle to it... and it has small holes for a pencil tip to fit into at various locations on it. I have one... the only thing I didn't like was the rubber feet...they came off about a week after I started using mine... and had to be replaced. :D

Defender.com, landfall navigation, west marine, bluewater books, all sell the navigation tools.

If you do use a mechanical pencil on-board, highly recommend you spray it down with Boeshield T9 to prevent it from corroding and jamming. I use the Pilot Vanishing Point mechanical pencils. They have a lead type indicator collar and an extended fine tip that retracts to protect it from breakage or damage. BTW, I generally use HB lead in the mechanical pencils, as it is a bit harder than 2B, so it doesn't break as readily IMHO.

SEMIJim said:
SD,

The GPS Plotter is a parallel rule, is it not? (Albeit a very nice one :).)

Where's a good place to get dividers like those?

Any protractor, or something special? (And what, precisely, do you use it for?)

I really gotta make a navigation book choice...

Thanks,
Jim
 
#7 ·
SEMIJim said:
I briefly tried to find dividers at the Weems & Plath site. Ironically, I found their site difficult to navigate! Perhaps I need to download their catalogue?

Thanks, Leff. Do you have a suggestion for lead hardness and, since you use a mechanical pencil (I've always preferred them) thickness?

Jim
These are the dividers that I use. I use it almost exclusively with the pencil lead in one of the arms (for marking off distances on the chart) instead of dual steel points. I haven't tried the ones that SD mentions, but they can be bought from Weems and Plath also.

Weems Plath Nautical Products; Commercial Grade Marine Navigation Tools and Gifts for Boating Enthusiasts

I haven't paid much attention to the lead hardness or thickness, but like SD mentions, softer leads will be easier on the charts. I tend towards thinner leads since I find it hard to be accurate with thicker lines (0.5mm is nice).

I learned coastal nav. with the ASA 105 text (by Tom Tursi or something like that). I wasn't blown away by the quality of the book, but it got the job done.

Regards,

Leff
 
#8 ·
Semi...may I tell you to throw away the parallel rules and plodding over to the compass rose AND most course line drawing. There is a $15 miracle called the Weems and Plath Course protractor that will allow you to plot a course (magnetic or true) between any two points in less than 10 seconds. Buy it and you will shower me with praise!! (G) I did all my navigation chart work in the cockpit in seconds and never used a parallel rule in 6 years of cruising. Next to the miracle cloth this is the holy grail of under $20 must have boat items!! This and some dividers are all you need.


http://us.st11.yimg.com/us.st.yimg.com/I/landfallnav_1958_22055106

For those of you who I've made curious...here's the one page "operators manual".
http://www.weems-plath.com/uploaded_files/instruction.255.pdf
 
#9 · (Edited)
By Jove, I believe you're right, cam! And at less than half the price of the Weems & Plath GPS Plotter, a real bargain! I think I'll go with that, the dividers/compass Leff recommended, Boater's Bowditch, that SD recommends, one of my good ol' mechanical pencils (mostly plastic, btw, SD) and a good eraser.

My plan is to use the hand-held GPS that's coming with the boat to establish position and plot the course this way--using my GPS/chartplotter/sonar for confirmation/verification.

Thanks, gentlemen, all of you!

Jim
 
#10 ·
Good enuf. ;)
 
#11 ·
camaraderie said:
Semi...may I tell you to throw away the parallel rules and plodding over to the compass rose AND most course line drawing. There is a $15 miracle called the Weems and Plath Course protractor that will allow you to plot a course (magnetic or true) between any two points in less than 10 seconds. Buy it and you will shower me with praise!! (G) I did all my navigation chart work in the cockpit in seconds and never used a parallel rule in 6 years of cruising. Next to the miracle cloth this is the holy grail of under $20 must have boat items!! This and some dividers are all you need.


http://us.st11.yimg.com/us.st.yimg.com/I/landfallnav_1958_22055106

For those of you who I've made curious...here's the one page "operators manual".
http://www.weems-plath.com/uploaded_files/instruction.255.pdf
Cam,

That is so cool! I'm going to order one tonight.

Regards,

Leff
 
#12 ·
Jim, you might also want to look at a "rolling ruler"

Staedtler Rolling Ruler

No traditional but a talented tool. I carried over a lot of drafting tools to my nav kit, and can only say that everyone may have slightly different tastes in what works best for them. Three-arm gizmos from the Weems & Plath collection...old circular slide rules...some tools do racing nav problems (wind/current/course) particularly, so I'd look at the catalogs and also look at some art supply (drafting) sources for alternatives as well.

As for the mechanical pencil <G> how precise do you plan to be? Some folks prefer a softer lead because it is blacker and easier to see, ditto a thicker lead. Probably the 0.5mm (1/2mm) is the most common mechanical pencil lead for drafting and general use, easy to get refills AND the leads are available in red and cyan (light blue) as well as a wide range of hardnesses. The harder lead makes a finer line--but if you don't need that tight a plot, sometimes a thicker line is just as good.<G> Odds are you can try a couple out at a local drafting or art supply store. Or just buy a bag of disposable mechanical pencils (the ones with the white erasers erase best, the orange "bic" ones make a nice crisp thin line) at a back-to-school sale, a buck for a dozen. A good thing to have when you can't find "THE" mechanical pencil too.<G>
 
#13 ·
I use two navigation triangles. I find them more convenient than a parallel rule or the rolling rule. The parallel rules with the protractor attached are from the aviation industry originally.

A number two pencil seems to work the best. Erasability is more of a factor than fineness of point. get a box of 'em. Save the short nub of the oldest one. It is a navigational fact, you can probably look it up in Bowditch, that a brand new, freshly sharpened pencil will not last for eight hours on any size vessel. The entire crew of said vessel can be interrogated at length and your new pencil will not show up. That is, until you reach port, at which time you'll be rolling in them. On the other hand, a two inch pencil stub will survive collisions, typhoons, and myriad other catastrophes untouched. Tie it or tape it near your navigation station or chart table and rest easy, secure in the knowledge you will always have a pencil. This information is not warranteed for pencils of greater length than two inches.

You may find that you use the same chart, and courses, repeatedly. Once you have established the course you wish to use for a particular voyage, you can ink it in. Wait until you are sure that is the one you want to lay down permanently. Don't ink it if you do not have the Scotch tape that you can write on with the pencil. Place the scotch tape over the inked course. This will allow you to plot positions with pencil, easily erase them, and protect the chart and the inked in course. do not use red ink.

As the Dog mentioned on dividers. Try them out before purchase. Everybody is a bit different. I do not care for the bow dividers but do like ones with long arms. They should be comfortable for one handed operation and be easily controllable that way. Keep their points sharp, using only the lightest pressure on the chart, so as to not punch a hole in the chart. A divider hole in a chart can turn the most taciturn navigator into a thoroughly po'd shipmate.
 
#14 ·
"A number two pencil seems to work the best. Erasability is more of a factor than fineness of point."

Oh, you like to make dirt? (Sharpening pencils.) Or, you were trained in covert weapons and found out the TSA will allow you to carry sharpened #2 pencils even when you can't bring your ice pick on board?<G>

I've found the Bic "orange" disposable mechanical pencils are really close to a really good #2 pencil--and they don't make dirt. The erasers on them are similar, but a white vinyl eraser really beats anything that comes on a pencil. They're also available at art supply stores, as "sticks" in holders that are similar to pens. At least one brand of the disposable mechanical pencils also come with the white vinyl eraser top, too.
 
#15 ·
I've got three, four... a half-dozen (I don't recall) mechanical pencils, and a bunch of leads, from back in the day when we did software design flow-charting by hand. Haven't seen use in years, and years. I've also got two-and-a-half Staedtler white vinyl drafting erasers (from back in the same time-period). So I suspect I'm pretty well set for pencils and erasers :).

I've even still got my old HP 15C calculator. (Good ol' RPN. Can't beat it :cool:) Batteries are dead, but that should be no problem.

Thanks for the other hints and tricks, guys :).

Jim
 
#16 ·
SEMIJim said:
I've even still got my old HP 15C calculator. (Good ol' RPN. Can't beat it :cool:) Batteries are dead, but that should be no problem.
Old calculator, eh? I've got one of these:


I was able to get the almanac to work until just three weeks ago. It's still a great astro calculator, and it must have been a huge time saver 25 years ago.

DATAMATH
 
#17 ·
I've found the Bic "orange" disposable mechanical pencils are really close to a really good #2 pencil--and they don't make dirt.
Being an architect from the dark ages - before CAD became mainstream, I have a number of old, brass barrel tech drafting pencils of various grades and lead thicknesses. I like the weight of these crafted instruments and prefer 0.3 mm and 0.7mm for chart plotting purposes. I must agree that sharpening pencils onboard is not the way to go.

I also have several German made K&E divider and compass sets, from my college days and some older collectable sets in leather cases. Very impressive weight and balance with some all brass and combination blued steel-brass, machine tooled components.

When working at the nav station with my archaic pencils, antique dividers and parallel rule, verse from The Rime of the Ancient Mariner echoes through my mind.
 
#20 ·
Yeah, that's what I'm finding, SH :(. The vendor SD pointed to for some of his suggestions has all three items, but shipping to get 'em here would cost nearly 50% of the cost of the items!

Hey! Anybody headed to the Detroit River powerboat races this weekend, from Wakefield, MA, or close by? :p

Jim
 
#23 ·
If you sign up for the USPS basic boating, or navigation courses, you get one of their proprietary plastic plotting protractors. The course is free, but the protractor and course book are included for a nominal course material's charge. It's perhaps the best value out there.

It's been many years since my wife and I took the course, but I still use my protractor on occasion.
 
#24 ·
hellosailor,

Yeah, but the time... I'd like to have them NLT mid-next-week. West Marine doesn't even list most, or maybe even any of them on their web site.

cam,

I noticed. But for the other two I'd have to go two other Amazon sellers. Again: The shipping would be a killer.

Good news: Persistence paid off. Found a place on the west side of Michigan that had all three items I wanted in stock. (Got the last Weems Protractor they had, too.) They think they'll even be able to ship today. So I might have 'em by Monday or so.

Oh yeah: And their prices were competitive :).

Thanks again for the help, guys!

Jim
 
#25 · (Edited)
Mechanical pencils, eh? How can you guys complicate things any more? I can think of a dozen ways to sharpen a pencil on a boat or ship. I'm at a loss as to how to fix a rusted or salt encrusted mechanical pencil, or fish the leads out of a dark bilge. But hey, it must work for ya.

I lost track of how many charts I'd cleaned up about a month on my second mate's license. The desirability of a soft lead is that it erases easily, if somewhat messily, and does not imprint the chart the way a harder lead does. A harder lead will leave it's imprint, and some lead, on the chart. You have to really press down with the eraser to get down into the imprint the harder lead makes, thus scrubbing away paper. If you are using the same chart for multiple plotting of DR tracks, those imprints can be distracting. Particularly under red light at night.

Val,

I purchased one of the first NC-77's to come out. What a great machine! Calculating Great Circle courses for trans oceanic passages went from a two hour ordeal to a seven minute, if that, breeze. Of course, I still charged the company the two hours OT for laying out the GC as the NC-77 was my own. I did not find it quite as handy for stars, but that's probably just me. Hidebound. I'll bet not many people know that you can use your GPS to calculate compass error. And I don't mean by monitoring CMG on it. Started out using the Tamaya for that as well. Wished I'd thought of that little nugget when I was debating Cam on the relative merits of celestial navigation. (g)
 
#26 ·
Sailaway-
"Mechanical pencils, eh? How can you guys complicate things any more? "
I'd argue that you've got it backwards. I've known some mechanical pencils to fail, or apparently fail, when a short lead jammed them. No problem, the ones sold for drafting and other "real" non-cosmetic use almost all have a cleaning needle on the underside of the lead, to clear jams. A sewing needle or straight pin also works.
Never had one rust or wear out, although I think my oldest is only 25-30 years old. But best of all? I can buy a box of disposable mechanicals that use .5mm lead for a buck, and if I add more lead (they're refillable, too) to each one, each one can outlast 5+ Ticonderogas. With no sharpening, no dirt to make, nothing to look for in the bilge, just one "pencil" that keeps writing for years.
If it breaks? I don't need to whip out something sharp or rough to make a new point, I can grab the next one. But, if that's a "complication" for you...obviously you've bought the Pardeys' old boat and still have no engine, right?< VBG >

The NC-77 was a miracle, but a used PalmIII for $25 and some nav software for $20 more becomes much easier to FIND. More versatile, easier to replace or carry a spare, too. John Manson's Pilot Navigator Software - Handheld Software for Pilots & Sailors strongly recommended, he's a very accommodating and responsive author/vendor as well.

Dunno how you can accept the NC-77 if a mechanical pencil is too complicated for your style, though. < VBG >
 
#30 ·
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