Plotting on paper charts

Refueler

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OK ... just out of interest ....

Recently a thread mentioned plotting tools such as Parallel Rulers ... Roller Rulers ... Plath Plotter ... Triangles .... etc.

Interested to know what people actually use on their boats ....

I have 3 methods when it comes to actual plotter instruments and one that is just simply adjustable pencil compass.

1. Nautical plotter by RIGEL ... consists of a square base protractor with a centre axle rivet. Next on top is a circular protractor that is used to set variation / deviation to correct bearings - then finally a long straight edge that provides the drawing edge ... all three rotate on that centre rivet. Its actually very good on a yacht as it sits on the chart with enough friction to avoid sliding about.
2. Two triangles that slide against each other - fine when boat is not moving about too much - but soon gets hard to keep steady on the chart.
3. Roller rules - best left as conversation items !! Hard to stop sliding on paper chart ...

The other is of course pencil compass and this I use to plot a position - but it cannot of course do bearings / course / track lines.

I used to have a 'Station Plotter' .... has 3 arms so that 3 bearings can be set on it and then placed on chart to give position ... each arm set at the item bearing was taken from. But its gone missing !! I now use a piece of clear film with white board pen ! (if I can be bothered !!)

OK ... last item : Compass correction in terms of bearings / course to steer etc. I know many have little sayings to remember how to correct from / to observed ... mine is the old Merchant Navy one :

Error East - Compass Least
Error West - Compass Best
 

Sandy

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A quick rummage in the chart table will find:
  • Charts;
  • Chart correcting pen;
  • Chart correcting stencil;
  • A long rule (450mm);
  • Breton Plotter (2);
  • Propelling pencil (2B);
  • Several 2B pencils;
  • Erasers;
  • Pens;
  • Tide atlases;
  • Pilot books;
  • Log Book (my own design A3); and a
  • Magnifying glass
Other useful kit:
  • Hand bearing compass; and
  • Some decent binoculars with compass.
 

Biggles Wader

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OK ... just out of interest ....

Recently a thread mentioned plotting tools such as Parallel Rulers ... Roller Rulers ... Plath Plotter ... Triangles .... etc.

Interested to know what people actually use on their boats ....

I have 3 methods when it comes to actual plotter instruments and one that is just simply adjustable pencil compass.

1. Nautical plotter by RIGEL ... consists of a square base protractor with a centre axle rivet. Next on top is a circular protractor that is used to set variation / deviation to correct bearings - then finally a long straight edge that provides the drawing edge ... all three rotate on that centre rivet. Its actually very good on a yacht as it sits on the chart with enough friction to avoid sliding about.
2. Two triangles that slide against each other - fine when boat is not moving about too much - but soon gets hard to keep steady on the chart.
3. Roller rules - best left as conversation items !! Hard to stop sliding on paper chart ...

The other is of course pencil compass and this I use to plot a position - but it cannot of course do bearings / course / track lines.

I used to have a 'Station Plotter' .... has 3 arms so that 3 bearings can be set on it and then placed on chart to give position ... each arm set at the item bearing was taken from. But its gone missing !! I now use a piece of clear film with white board pen ! (if I can be bothered !!)

OK ... last item : Compass correction in terms of bearings / course to steer etc. I know many have little sayings to remember how to correct from / to observed ... mine is the old Merchant Navy one :

Error East - Compass Least
Error West - Compass Best
When I was in the Merchant Navy we used a nice little ditty to get True from Compass
Compass+Deviation=Magnetic+Variation=True.
Remembered by-----Captains Dick Makes Virgins Tremble.
I have forgotten almost everything else but always remember that one!
 

Refueler

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When I was in the Merchant Navy we used a nice little ditty to get True from Compass
Compass+Deviation=Magnetic+Variation=True.
Remembered by-----Captains Dick Makes Virgins Tremble.
I have forgotten almost everything else but always remember that one!

My first company was Joe Shell ... and there was an old song about a smokey Joe Shell boat ... I wish I could remember it ... but its years since I heard it.

Ok - thread drift .... think I've told this one before on RtR .. but here goes.

Shell had a fleet of old small tankers out in Singapore that supplied around the region ... quite a few used to be anchored up off Singapore waiting load or orders etc.
Radar was being fitted to new builds and of course crews on these were proud of their gear !
One old tanker in Singapore decided to have a laugh and constructed from a wood pole and a few crates - a mock radar scanner ...
Shell Eastern Office is supposed to have received a curt message from Master of a new Shell ship that arrived which was waiting installation of promised Radar .. about the old tanker in anchorage with a Radar ..
 

dunedin

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When I was in the Merchant Navy we used a nice little ditty to get True from Compass
Compass+Deviation=Magnetic+Variation=True.
Remembered by-----Captains Dick Makes Virgins Tremble.
I have forgotten almost everything else but always remember that one!
Our RN Reserve teacher used a similar adage the other way around - True Virgins Make Dull Company :)

Funny I can’t remember much else of my Higher Navigation course!
 

Poignard

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Has anyone ever seen one of these?

It's a Blundell Harling 'Portland'GPS Plotter intended to enable quick and easy plotting of Lat/Long co-ordinates from a GPS, almanac, or waypoint list onto a chart, and vice-versa.

It also functions as a simple parallel rule

I bought this years ago but have never got around to using it. The plastic case is a bit battered but, judging by the condition of the non-slip rubber feet underneath, the actual instrument doesn't look as if it has been used.

[I could sell it if anyone is interested ;)]

BH Portland GPS Plotter (1).jpg
 

veshengro

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Parallel Rule, Brass Dividers, Breton Plotter, 2 B Pencils etc:

For Refueler's benefit, I remember a rude shanty that began..

There was once a mad Shell Tanker man from the Port of Abadan
who ran off with the Daughter of the local Headman...

I think that is the only line which will not get me banned
Back in the days when it was The Persian Gulf. :LOL:
 

MADRIGAL

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A quick rummage in the chart table will find:
  • Charts;
  • Chart correcting pen;
  • Chart correcting stencil;
  • A long rule (450mm);
  • Breton Plotter (2);
  • Propelling pencil (2B);
  • Several 2B pencils;
  • Erasers;
  • Pens;
  • Tide atlases;
  • Pilot books;
  • Log Book (my own design A3); and a
  • Magnifying glass
Other useful kit:
  • Hand bearing compass; and
  • Some decent binoculars with compass.
I especially like my binoculars with built-in compass.
 

Boathook

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Has anyone ever seen one of these?

It's a Blundell Harling 'Portland'GPS Plotter intended to enable quick and easy plotting of Lat/Long co-ordinates from a GPS, almanac, or waypoint list onto a chart, and vice-versa.

It also functions as a simple parallel rule

I bought this years ago but have never got around to using it. The plastic case is a bit battered but, judging by the condition of the non-slip rubber feet underneath, the actual instrument doesn't look as if it has been used.

[I could sell it if anyone is interested ;)]

View attachment 171453
Thats what I mainly use when I plot a position. Also have a rolling parallel ruler.
 

ctva

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I only ever used the Portland type plotter as it's so simple. Those John Goode ones pictured above are in a drawer somewhere as well.

As to remembering variation, I've always used the hill version, add for mag, get rid for grid. However this is all about to be reversed over the next few years here in the UK...
 

Daydream believer

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Has anyone ever seen one of these?

It's a Blundell Harling 'Portland'GPS Plotter intended to enable quick and easy plotting of Lat/Long co-ordinates from a GPS, almanac, or waypoint list onto a chart, and vice-versa.

It also functions as a simple parallel rule

I bought this years ago but have never got around to using it. The plastic case is a bit battered but, judging by the condition of the non-slip rubber feet underneath, the actual instrument doesn't look as if it has been used.

[I could sell it if anyone is interested ;)]

View attachment 171453
I have one & do use it when setting points for new charts on my yeoman plotter
 

Stemar

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Got the kit on board, but haven't used it for years.

About the only time I use paper charts is for route planning at home. I keep a passage log where I note our position every hour on passage but out of sight of land (rare theses days), I go from waypoint to waypoint.
 

rogerthebodger

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Having started work at 16 as a mechanical design draftsman using a drawing board I still have all my drafting tools.

I also used then for vector diagrams for force analysis and velocity diagrams so navigation came as second nature
 

Refueler

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One boat - guy had obtained a small draftsmans fixed 'cantilever' arm .... fixed to his chart table ... gave him quite a steady form to use ... it also hinged up so he could still open the chart top.
 

rogerthebodger

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One boat - guy had obtained a small draftsmans fixed 'cantilever' arm .... fixed to his chart table ... gave him quite a steady form to use ... it also hinged up so he could still open the chart top.

I could do that on my chart table using a tee square on the left hand. side except for the fiddle rails would need to be removed

My TV computer is mounted on a cantilever are so I could attach a drawing board to that if I wished
 

Skylark

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I share the view that on a small boat, a parallel rule is the work of the Devil.

In the classroom, the ubiquitous Portland/Bretton plotter wins every time.

On my boat I like to use the Portland Protractor. No moving parts is an advantage.

I do have a Portland Station Pointer for 3-bearing fixes but confess that I rarely use it.

How about the sharp thingies? I often find compasses either too tight or too lose. My strong preference is a Weems & Plath 7 inch ultralight, as shown in the picture. The adjusting screw has a nice light touch with little to no backlash.

For a pencil, I've always used a Pentel mechanical pencil with 0.7mm 2B lead.

Nav Instruments.jpg
 
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