Rolling ruler or Parallel plotter?

[Moontide]

Another vote for triangles - way easier, especially when in sloppy stuff

[El Pinguino]

Originally Posted by Reefmagnet

I settled on a portland plotter for use in tight spaces

Ditto..... // rules and triangles are fine on a nice big chart table on a nice big ship but on a folded chart on a yacht's small chart table Portland plotters are the way to go.

And also ... while a good full sized set of 'Capt Field's Improved' are a wonderful bit of kit the little 12 or 15 inch 'yacht' ones are usually miserable 'consumer grade' things.

And also also... the compass rose on your folded chart will invariably be over by the fiddle and under your coffee cup......

[Jim Cate]

When I was doing lots of chart work, what I really lusted after was a drafting machine! To me, this seems the ideal answer on a decent sized chart table. Never got around to mounting one, and mostly used parallel rules. Tried a roller (perhaps not a very good one) and found it useless at sea.

Jim

[Deltasailor]

Originally Posted by Cadence

Mark they are a hell of a lot cheaper. Lining up Side HH with side HH on page whatever is a bitch. It does suffice for coastal cruising. Saves a bunch of storage. Acquiring full sized charts at any give point for a remote destination can prove to be problematical. It beats relying on electronics entirely which can leave you hanging out to dry.

I agree with Mark proper charts are the best. I use a parallel rule and keep an hourly log. It gives me something to do on long night watches and as has happened the log weeded up. I had only to go back an hour!
Once in the dark sailing the east coast of Spain my chart did not have enough detail I used a road map to identify towns and did a running fix to fix my position on my paper chart. Long before chart plotters!

[barnakiel]

I use triangles on our boat. This is what I got used to at school and our nav table is small.

I have used parallel rullers on full size Admiralty size tables. They are fine when you have enough space.

There are other nice devices but somehow with triangles I always managed draw whatever I needed to draw.

Cheers,

b.

[Pelagic]

There still exists today many remote coastlines, approaches and harbours where the electronic charts do not have the details of the original surveyed paper charts.

I carry charts for those places and prepare them ahead of time with safe course/ reciprocals and parallel index safety and danger radar CPA's for using offset EBLs

So that means drawing many 90° lines and measurements off of your course line.

Nothing does this quicker and more accurately than a pair of Triangles

[NevisDog]

Parallel rulers and roller ruler can drive you mad on a small boat; a pair of navigational triangles are so much easier, or the RYA version of the Portland Plotter (from Blundell Harling) is even easier on small chart pages. I often print off A4 paper charts on board from OpenCPN, use them until they disintegrate then print some more - only cost is for the paper and ink.

If anyone else out there gets their full-size charts laminated (making them almost indestructible, but of course impossible to update) then don't go for the 'silk' (low reflection) finish, as the wax pencil lines are so much harder to wipe off than with the smooth plastic.

[Capt.Don]

Originally Posted by Jim Cate

Well, I've found that the rollers often slip on the shiny glass of the MFD when I try to use them, but then the long legs of the parallel rules catch on the knobs.

What's a modern navigator to do?

Jim

And the dividers put little holes in the screen

[hellosailor]

The Portland Plotter is either a copy or the daddy of the naval aviation plotter, and that was meant so that a pilot could use it on their knee. Vastly underappreciated for years.

But since there are so many rolling rulers available under ten bucks on Amazon, and so many more that are larger and supposedly "Professional" for under $25 with free Prime returns...

Why not just order a cheap one, or a better one with the option of a return, and see how your hands like it?

Nav tools, drafting tools, things like questions of which kind of pencil (lead? mechanical? what kind of lead? thin? hard? thicker?) are really something you need to get your hands on to see what makes them happy.

Now, should I wear the brown socks? Or the blue ones?

[qwert]

Even simpler and smaller is the 'Douglas combined protractor and parallel rule' which measures 5 inches x 5 inches x 1/16 and is completely flat. It's so simple its really hard to get confused if you're as navigationally challenged as myself ............

[StuM]

Inherited these two when I bought the current boat:

[Reefmagnet]

Originally Posted by hellosailor

...

things like questions of which kind of pencil (lead? mechanical? what kind of lead? thin? hard? thicker?) are really something you need to get your hands on to see what makes them happy.

...

Pencils are soooo 20th century. Fine whiteboard markers for laminated charts or erasable pens for paper.

[rhubstuff]

I've used the same Mk II Weems and Plath Air Navigation Plotter/Protractor exclusively for 49 years. One thin piece of plastic, no moving parts, accurate to 1/2 degree, works on any surface, and cheap.

[Alan Mighty]

Originally Posted by hellosailor

The Portland Plotter is either a copy or the daddy of the naval aviation plotter, and that was meant so that a pilot could use it on their knee. Vastly underappreciated for years.

The naval aviation plotter comes later than the naval course plotter. Or earlier, depending on your point of view.

The name 'Portland Plotter' is an unfortunate accident that disguises the real origins of the device. And that unfortunate accident is partly because of Anglophonic disregard for anything that was not developed by Anglophones. Which is to say that I think the real history of the device requires a Francophone scholar to reveal.

To make the story short:

* Admiral Jean Émile Paul Cras (1879-1932) came up with an improved course plotter, the Cras Plotter (Règle Cras) that was standard use for the navy of France;

* a captain of fishing vessels and merchant vessels, Yvonnick Guéret (1933-2002), improved the Cras plotter in 1964 and called it Rapporteur Breton (let's call it the Breton plotter). In 1966 YG set up a company to manufacture and market the Breton plotter.

* a company in the land known as Perfidious Albion (usually abbreviated as UK), Blundell Harling, had been producing a line of chart table instruments under the brand name 'Portland'. Blundell Harling began producing a copy of the Breton plotter, initially branding its copy with the ungainly name of the Portland Series Breton plotter (Rapporteur Breton). Blundell Harling shortened the name a little but for many years still included 'Rapporteur Breton' in the name, showing that not all residents of Albion disrespected Breton or France.

* other 'Albion perfide' companies and companies in the US (including Weems & Plath), copied the Blundell Harling device, using names including 'Portland course plotter' and 'Weems protractor'.

* in 1991 Guéret was granted French patents for two tiny parts of his Breton plotter: his use of red and green colours and his use of reverse print numerals. In case you are interested, those patents are FR2675895 and FR2679328.

* a couple of small UK firms have created improved versions of the Breton plotter. From time to time small numbers of those superb improved versions have been sold at chandlers in the UK. If you're lucky, you have one of them. I'm jealous. I use a Weems protactor and think it's wonderful for work on a small boat in a seaway. I've seen a couple of the improved versions and wish I had one.

* a company in France still produces a Breton plotter and claims it is the direct descendant of Guéret. Take a Captain Cook by pointing your browser to: rapporteurbreton.com The same company also produces the Cras Plotter (which looks very much like the naval aviation plotter). If you're keen you can buy one of each and have a bit of real navigation history.

[Alan Mighty]

Originally Posted by StuM

Inherited these two when I bought the current boat:

Versions of the Cras Plotter! Lucky you, Stu.