09 Apr 2006 21:04:58
Teredo
Portland Plotter Instructions

I've bought a boat, and with it came the plotter, alas no instructions.

Can anyone guide me to a site where I might read up?



10 Apr 2006 08:25:00
Pete Styles
Re: Portland Plotter Instructions



Teredo wrote:

>I've bought a boat, and with it came the plotter, alas no instructions.
>
>Can anyone guide me to a site where I might read up?
>
>
Basically, its a simple but clever device which is very easy to use.
To get a compass bearing from the chart, lay the plotter on the chart in
the required direction and then rotate the central circle until the
graticule (grid lines) align with any convenient lat or long grid line
on the chart. Then read off the bearing against the appropriate
deviation scale (marked in degrees east or west). Note that the main
part of the plotter is labeled 'direction of course' (or something
similar) and the rotating circle is marked 'north' - obey these
instructions!
To plot a line on the chart from a compass bearing, set up the plotter
with the compass bearing aligned with the appropriate deviation and then
align the graticules with the chart, again heeding north.
Once you get the hang of it, you'll wonder how you ever managed with
parallel rules and having to remember whether to add or subtract deviation.
HTH
Pete.



10 Apr 2006 10:35:12
Aquarius Yachting
Re: Portland Plotter Instructions

On Mon, 10 Apr 2006 08:25:00 GMT, Pete Styles wrote:

>Once you get the hang of it, you'll wonder how you ever managed with
>parallel rules and having to remember whether to add or subtract deviation.

I'm doing the RYA Day Skipper course. I tried to get on with the PP,
but hated it. I much prefer a pair of triangular protractors, I have a
dim memory of using these in Technical Drawing at school.


--

Nigel M

Sail in a Bavaria 47 around the Greek Islands
http://www.aquariusyachting.co.uk/


10 Apr 2006 10:46:11
NotMyRealName
Re: Portland Plotter Instructions

In message <wDo_f.24661$g76.12775@newsfe2-gui.ntli.net >, Pete Styles
<peter.styles@bioch.ox.ac.uk > writes
>
>
>Teredo wrote:
>
>>I've bought a boat, and with it came the plotter, alas no instructions.
>>
>>Can anyone guide me to a site where I might read up?
>>
>Basically, its a simple but clever device which is very easy to use.
>To get a compass bearing from the chart, lay the plotter on the chart
>in the required direction and then rotate the central circle until the
>graticule (grid lines) align with any convenient lat or long grid line
>on the chart. Then read off the bearing against the appropriate
>deviation scale (marked in degrees east or west). Note that the main
>part of the plotter is labeled 'direction of course' (or something
>similar) and the rotating circle is marked 'north' - obey these instructions!
>To plot a line on the chart from a compass bearing, set up the plotter
>with the compass bearing aligned with the appropriate deviation and
>then align the graticules with the chart, again heeding north.
>Once you get the hang of it, you'll wonder how you ever managed with
>parallel rules and having to remember whether to add or subtract
>deviation.
>HTH
>Pete.
>

Pete

I think you are describing a Breton plotter - AFAIR Portland plotters do
a similar job, but have no moving parts.

Spike


10 Apr 2006 11:21:10
Pete
Re: Portland Plotter Instructions



NotMyRealName wrote:
> In message <wDo_f.24661$g76.12775@newsfe2-gui.ntli.net>, Pete Styles
> <peter.styles@bioch.ox.ac.uk> writes
>
>
> Pete
>
> I think you are describing a Breton plotter - AFAIR Portland plotters do
> a similar job, but have no moving parts.
>
> Spike

Spike
No, what I was describing was:
http://www.sailboats.co.uk/Product~Portland_Course_Plotter_PLA0132.html

I've never seen a Breton plotter, but looking at eg:
http://www.seachest.co.uk/acatalog/info_1236.html
suggests that they are similar.

However, I do have memories of a fixed rectangular plotter on a charter
boat many years ago, and that I found it almost totally confusing. What
it was called escapes me.
Pete.



10 Apr 2006 12:32:45
Martin
Re: Portland Plotter Instructions

On Mon, 10 Apr 2006 10:46:11 +0100, NotMyRealName
<spike@notmegov.com.yuk > wrote:

>In message <wDo_f.24661$g76.12775@newsfe2-gui.ntli.net>, Pete Styles
><peter.styles@bioch.ox.ac.uk> writes
>>
>>
>>Teredo wrote:
>>
>>>I've bought a boat, and with it came the plotter, alas no instructions.
>>>
>>>Can anyone guide me to a site where I might read up?
>>>
>>Basically, its a simple but clever device which is very easy to use.
>>To get a compass bearing from the chart, lay the plotter on the chart
>>in the required direction and then rotate the central circle until the
>>graticule (grid lines) align with any convenient lat or long grid line
>>on the chart. Then read off the bearing against the appropriate
>>deviation scale (marked in degrees east or west). Note that the main
>>part of the plotter is labeled 'direction of course' (or something
>>similar) and the rotating circle is marked 'north' - obey these instructions!
>>To plot a line on the chart from a compass bearing, set up the plotter
>>with the compass bearing aligned with the appropriate deviation and
>>then align the graticules with the chart, again heeding north.
>>Once you get the hang of it, you'll wonder how you ever managed with
>>parallel rules and having to remember whether to add or subtract
>>deviation.
>>HTH
>>Pete.
>>
>
>Pete
>
>I think you are describing a Breton plotter - AFAIR Portland plotters do
>a similar job, but have no moving parts.

You can see here that your recollection is wrong -
http://www.allgadgets.co.uk/ag/product.asp?dept_id=6&pf_id=AG3907

I think you are mixing it up with a Portland Protractor
http://www.datemadirect.nl/php/artinfo.php4?A1450130
--
Martin


10 Apr 2006 11:33:24
Pete
Re: Portland Plotter Instructions



Aquarius Yachting wrote:
> On Mon, 10 Apr 2006 08:25:00 GMT, Pete Styles wrote:
>
>
>>Once you get the hang of it, you'll wonder how you ever managed with
>>parallel rules and having to remember whether to add or subtract deviation.
>
>
> I'm doing the RYA Day Skipper course. I tried to get on with the PP,
> but hated it. I much prefer a pair of triangular protractors, I have a
> dim memory of using these in Technical Drawing at school.
>
>

I'm very surprised. What is it that you so dislike? I know that you
don't comment on parallel rules, but IMHO they are difficult on the
kitchen table, and virtually impossible on a small chart table which is
going up and down, so almost anything has to be better. I love the PP
because I find it quick and very resistant to making mistakes of the
CADET type.



10 Apr 2006 14:09:49
Aquarius Yachting
Re: Portland Plotter Instructions

On Mon, 10 Apr 2006 12:32:45 +0200, Martin wrote:

My understanding is that a Portland and a Breton are similar, apart
from the size. This is confirmed by the following, link below:

"Breton Plotter. The original plotter as developed by Captain Yvonnick
Gueret. This is slightly smaller than the Portland Plotter but works
on exactly the same principal [sic]."

<http://www.seachest.co.uk/acatalog/info_1236.htmlcolor=#0000FF> >

>I think you are mixing it up with a Portland Protractor
>
http://www.datemadirect.nl/php/artinfo.php4?A1450130

I would call that a square protractor.

--

Nigel M

Sail in a Bavaria 47 around the Greek Islands
http://www.aquariusyachting.co.uk/


10 Apr 2006 06:47:32
peter
Re: Portland Plotter Instructions

Aquarius Yachting wrote:
> On Mon, 10 Apr 2006 12:32:45 +0200, Martin wrote:
>
> My understanding is that a Portland and a Breton are similar, apart
> from the size. This is confirmed by the following, link below:
>
> "Breton Plotter. The original plotter as developed by Captain Yvonnick
> Gueret. This is slightly smaller than the Portland Plotter but works
> on exactly the same principal [sic]."

I seem to recall reading that it's purely a trademark issue - the name
'Breton Plotter' is a registered trademark, so anyone who manufactures
them other than the company owning the trademark has to call them
something different.



10 Apr 2006 16:24:16
Martin
Re: Portland Plotter Instructions

On Mon, 10 Apr 2006 14:09:49 +0100, Aquarius Yachting
<reply@thegroup.email.invalid > wrote:

>On Mon, 10 Apr 2006 12:32:45 +0200, Martin wrote:
>

I didn't write this

>My understanding is that a Portland and a Breton are similar, apart
>from the size. This is confirmed by the following, link below:
>
>"Breton Plotter. The original plotter as developed by Captain Yvonnick
>Gueret. This is slightly smaller than the Portland Plotter but works
>on exactly the same principal [sic]."
>

I did write this

><http://www.seachest.co.uk/acatalog/info_1236.html>
>
>>I think you are mixing it up with a Portland Protractor
>>http://www.datemadirect.nl/php/artinfo.php4?A1450130
>
>I would call that a square protractor.

but none the less it has been sold for at least 40 years as a Portland
Protractor and for that reason people call it a Portland Protractor.

--
Martin


10 Apr 2006 15:34:01
Aquarius Yachting
Re: Portland Plotter Instructions

On Mon, 10 Apr 2006 16:24:16 +0200, Martin wrote:

>I didn't write this

No, you wrote the quoted text, do try to keep up ;-0

--

Nigel M

Sail in a Bavaria 47 around the Greek Islands
http://www.aquariusyachting.co.uk/


10 Apr 2006 15:32:28
chris
Re: Portland Plotter Instructions

"peter" <peter@pandasys.co.uk > wrote in message
news:1144676852.264921.3100@j33g2000cwa.googlegroups.com...
> Aquarius Yachting wrote:
> > On Mon, 10 Apr 2006 12:32:45 +0200, Martin wrote:
> >
> > My understanding is that a Portland and a Breton are similar, apart
> > from the size. This is confirmed by the following, link below:
> >
> > "Breton Plotter. The original plotter as developed by Captain Yvonnick
> > Gueret. This is slightly smaller than the Portland Plotter but works
> > on exactly the same principal [sic]."
>
> I seem to recall reading that it's purely a trademark issue - the name
> 'Breton Plotter' is a registered trademark, so anyone who manufactures
> them other than the company owning the trademark has to call them
> something different.
>
IMHO Whatever you choose to call them, I think the Portland plotter is
brilliantly simple to use but the square protractor is a virtually useless
gimmick.

--
ChrisR
to reply please erase any numerals from email address




10 Apr 2006 16:18:44
News f2s
Re: Portland Plotter Instructions


"chris" <chris1@yachtsmen2.co.uk > wrote in message
news:443a6ce9@nntp.onyx.net...

> IMHO Whatever you choose to call them, I think the Portland
> plotter is
> brilliantly simple to use but the square protractor is a
> virtually useless
> gimmick.

The square protractor ('Douglas' Combined Protractor & Parallel
Rule) was standard issue to RAF aircrew in WW2. It was easy to
stow and easy to use in confined spaces. Everything the
Portland plotter does can be done with the Square protractor,
which is, agreed, a little less intuitive to use. Yes, I've
still got mine.

At some stage the design of AM stores ref 6B/47 was re-labelled a
'Portland Protractor', and then produced in different sizes.

I think those who use the square protractor might call it
brilliantly simple, whilst the Portland, perhaps,
adds un-necessary gimmiks :-)
--
JimB
http://www.jimbaerselman.f2s.com/
for opinions comparing Greek cruising areas, N Spain too






10 Apr 2006 08:26:29
Re: Portland Plotter Instructions

News f2s wrote:

> I think those who use the square protractor might call it
> brilliantly simple, whilst the Portland, perhaps,
> adds un-necessary gimmiks :-)


Cue 500 post thread shouting match on between those who say you
shouldn't rely on the Portland Plotter because it might 'go wrong' and
those who use it all the time without problem.



10 Apr 2006 17:27:38
Martin
Re: Portland Plotter Instructions

On Mon, 10 Apr 2006 15:32:28 +0100, "chris" <chris1@yachtsmen2.co.uk >
wrote:

>IMHO Whatever you choose to call them, I think the Portland plotter is
>brilliantly simple to use but the square protractor is a virtually useless
>gimmick.

Despite which we use the protractor most of the time in preference to
the plotter.
--
Martin


10 Apr 2006 17:49:17
Martin
Re: Portland Plotter Instructions

On Mon, 10 Apr 2006 16:18:44 +0100, "News f2s"
<jimb@seesignature.f2s.com > wrote:

>
>"chris" <chris1@yachtsmen2.co.uk> wrote in message
>news:443a6ce9@nntp.onyx.net...
>
>> IMHO Whatever you choose to call them, I think the Portland
>> plotter is
>> brilliantly simple to use but the square protractor is a
>> virtually useless
>> gimmick.
>
>The square protractor ('Douglas' Combined Protractor & Parallel
>Rule) was standard issue to RAF aircrew in WW2. It was easy to
>stow and easy to use in confined spaces. Everything the
>Portland plotter does can be done with the Square protractor,
>which is, agreed, a little less intuitive to use. Yes, I've
>still got mine.
>
>At some stage the design of AM stores ref 6B/47 was re-labelled a
>'Portland Protractor', and then produced in different sizes.
>
>I think those who use the square protractor might call it
>brilliantly simple, whilst the Portland, perhaps,
>adds un-necessary gimmiks :-)

LOL Brilliant!
--
Martin


10 Apr 2006 17:50:06
Martin
Re: Portland Plotter Instructions

On 10 Apr 2006 08:26:29 -0700, toad_oftoadhall@yahoo.co.uk wrote:

>News f2s wrote:
>
>> I think those who use the square protractor might call it
>> brilliantly simple, whilst the Portland, perhaps,
>> adds un-necessary gimmiks :-)
>
>
>Cue 500 post thread shouting match on between those who say you
>shouldn't rely on the Portland Plotter because it might 'go wrong' and
>those who use it all the time without problem.

Portland Protractors can't go wrong - they have no moving parts.
--
Martin


10 Apr 2006 15:49:32
Pete Styles
Re: Portland Plotter Instructions

This is a multi-part message in MIME format.
--------------010701030407070806090508
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit



toad_oftoadhall@yahoo.co.uk wrote:

>News f2s wrote:
>
>
>
>>I think those who use the square protractor might call it
>>brilliantly simple, whilst the Portland, perhaps,
>>adds un-necessary gimmiks :-)
>>
>>
>
>
>Cue 500 post thread shouting match on between those who say you
>shouldn't rely on the Portland Plotter because it might 'go wrong' and
>those who use it all the time without problem.
>
I've argued here in the past that those who say that you shouldn't rely
on GPS incase it goes wrong/batteries go flat/satelites fall out of the
sky etc., that logic dictates that everyone should therefore carry a
spare PP just in case the primary one gets trodden on. :-)


--------------010701030407070806090508
Content-Type: text/html; charset=us-ascii
Content-Transfer-Encoding: 7bit

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" >
<html >
<head >
<meta http-equiv="Content-Type" content="text/html;charset=ISO-8859-1" >
<title ></title>
</head >
<body text="#000000" bgcolor="#ffffff" >
<br >
<br >
<a class="moz-txt-link-abbreviated" href="mailto:toad_oftoadhall@yahoo.co.uk" >toad_oftoadhall@yahoo.co.uk</a> wrote:<br>
<blockquote type="cite"
cite="mid1144682789.520181.319610@i39g2000cwa.googlegroups.com" >
<pre wrap="" >News f2s wrote:

</pre >
<blockquote type="cite" >
<pre wrap="" >I think those who use the square protractor might call it
brilliantly simple, whilst the Portland, perhaps,
adds un-necessary gimmiks :-)
</pre >
</blockquote >
<pre wrap="" ><!---->

Cue 500 post thread shouting match on between those who say you
shouldn't rely on the Portland Plotter because it might 'go wrong' and
those who use it all the time without problem.</pre >
</blockquote >
I've argued here in the past that those who say that you shouldn't rely
on GPS incase it goes wrong/batteries go flat/satelites fall out of the
sky etc., that logic dictates that everyone should therefore carry a
spare PP just in case the primary one gets trodden on. :-)<br >
<br >
</body >
</html >

--------------010701030407070806090508--



10 Apr 2006 15:50:34
Pete Styles
Re: Portland Plotter Instructions



Martin wrote:

>On 10 Apr 2006 08:26:29 -0700, toad_oftoadhall@yahoo.co.uk wrote:
>
>
>
>>News f2s wrote:
>>
>>
>>
>>>I think those who use the square protractor might call it
>>>brilliantly simple, whilst the Portland, perhaps,
>>>adds un-necessary gimmiks :-)
>>>
>>>
>>Cue 500 post thread shouting match on between those who say you
>>shouldn't rely on the Portland Plotter because it might 'go wrong' and
>>those who use it all the time without problem.
>>
>>
>
>Portland Protractors can't go wrong - they have no moving parts.
>
...but you can still tread on them!



10 Apr 2006 19:18:56
Martin
Re: Portland Plotter Instructions

On Mon, 10 Apr 2006 15:49:32 GMT, Pete Styles
<peter.styles@bioch.ox.ac.uk > wrote:

>
>
>toad_oftoadhall@yahoo.co.uk wrote:
>
>>News f2s wrote:
>>
>>
>>
>>>I think those who use the square protractor might call it
>>>brilliantly simple, whilst the Portland, perhaps,
>>>adds un-necessary gimmiks :-)
>>>
>>>
>>
>>
>>Cue 500 post thread shouting match on between those who say you
>>shouldn't rely on the Portland Plotter because it might 'go wrong' and
>>those who use it all the time without problem.
>>
>I've argued here in the past that those who say that you shouldn't rely
>on GPS incase it goes wrong/batteries go flat/satelites fall out of the
>sky etc., that logic dictates that everyone should therefore carry a
>spare PP just in case the primary one gets trodden on. :-)

I know from experience that spilt whiskey and rum doesn't wash off the
scale.
--
Martin


10 Apr 2006 10:54:57
Re: Portland Plotter Instructions

Martin wrote:
> On 10 Apr 2006 08:26:29 -0700, toad_oftoadhall@yahoo.co.uk wrote:
>
> >News f2s wrote:
> >
> >> I think those who use the square protractor might call it
> >> brilliantly simple, whilst the Portland, perhaps,
> >> adds un-necessary gimmiks :-)
> >
> >
> >Cue 500 post thread shouting match on between those who say you
> >shouldn't rely on the Portland Plotter because it might 'go wrong' and
> >those who use it all the time without problem.
>
> Portland Protractors can't go wrong - they have no moving parts.

My Portland Plotter has a moving disc. It has the label 'Portland
Course Plotter'.

...and I've trodden on two and broken them.



10 Apr 2006 20:53:04
Alan Frame
Re: Portland Plotter Instructions

Martin <me@privacy.net > wrote:
> <peter.styles@bioch.ox.ac.uk> wrote:
> >Martin wrote:
> >>On 10 Apr 2006 08:26:29 -0700, toad_oftoadhall@yahoo.co.uk wrote:
> >>>News f2s wrote:

> >>>>I think those who use the square protractor might call it
> >>>>brilliantly simple, whilst the Portland, perhaps,
> >>>>adds un-necessary gimmiks :-)
> >>>>
> >>>Cue 500 post thread shouting match on between those who say you
> >>>shouldn't rely on the Portland Plotter because it might 'go wrong' and
> >>>those who use it all the time without problem.
> >>
> >>Portland Protractors can't go wrong - they have no moving parts.
> >>
> >...but you can still tread on them!
>
> and slip and break a leg? :-)

Yeah, but you've got a spare leg, haven't you? ;-)

rgds, Alan
--
99 Ducati 748BP, 95 Ducati 600SS, 81 Guzzi Monza, 74 MV Agusta 350
"Ride to Work, Work to Ride" SI# 7.067 DoD#1930 PGP Key 0xBDED56C5


10 Apr 2006 20:18:54
Ronald Raygun
Re: Portland Plotter Instructions

Martin wrote:

> On Mon, 10 Apr 2006 15:49:32 GMT, Pete Styles
> <peter.styles@bioch.ox.ac.uk> wrote:
>>I've argued here in the past that those who say that you shouldn't rely
>>on GPS incase it goes wrong/batteries go flat/satelites fall out of the
>>sky etc., that logic dictates that everyone should therefore carry a
>>spare PP just in case the primary one gets trodden on. :-)
>
> I know from experience that spilt whiskey and rum doesn't wash off the
> scale.

That's ambiguous. Which of the following are you saying?

(1) The ink with which the plotter's scale is printed will not be
washed off by the odd spillage of alcohol.

(2) If you spill alcohol on the plotter's scale it will leave stains
which can't be washed off.

What does the GPS do when you spill spirits on it?



11 Apr 2006 00:45:26
chris
Re: Portland Plotter Instructions

I suppose like the marmite advert says, we apparently love it or hate it!
Maybe its the same for plotters versus protractors and perhaps the reason
both are still sold :-)

I agree the Douglas Protractor is attractive for its simplicity (which is
why I bought one) but I personally found the Portland plotter quicker and
easier to deploy on a restricted chart table.
--
ChrisR
to reply please erase any numerals from email address

"Martin" <me@privacy.net > wrote in message
news:g9uk3299rasjj262he10jpqdfeqcgd2tjv@4ax.com...
> On Mon, 10 Apr 2006 15:32:28 +0100, "chris" <chris1@yachtsmen2.co.uk>
> wrote:
>
> >IMHO Whatever you choose to call them, I think the Portland plotter is
> >brilliantly simple to use but the square protractor is a virtually
useless
> >gimmick.
>
> Despite which we use the protractor most of the time in preference to
> the plotter.
> --
> Martin




11 Apr 2006 02:22:37
Re: Portland Plotter Instructions

Pete Styles wrote:

> I've argued here in the past that those who say that you shouldn't rely
> on GPS incase it goes wrong/batteries go flat/satelites fall out of the
> sky etc., that logic dictates that everyone should therefore carry a
> spare PP just in case the primary one gets trodden on. :-)

Funny, I was watching the 'Sailing Watch' thread to see if similar
logic was applied to wearing a wrist watch when sailing. It wasn't.



11 Apr 2006 10:35:02
Graham Frankland
Re: Portland Plotter Instructions

"Martin" <me@privacy.net > wrote in message
news:rq4l325b7ovui57pfjtedqc103g1vj326e@4ax.com...
> I know from experience that spilt whiskey and rum doesn't wash off the
> scale.
>
Neither does acetone - glued mine up a treat when I spilled some on it.

Graham.