DP Tool Club 8/CDASC08.ISO/VRAC/SLY138.ZIP/SIY1_C.TXT

Text File | 1993-02-22 | 21KB | 475 lines

SIY1_C.TXT     Plot a Map from a Land Description the Cheapie Way             9

                                 Chapter 1_C


              Plot a Map from a Land Description the Cheapie Way


For this chapter you will need:

a) These instructions, copies of the necessary graphs, and some graph paper.
These are available for five bux [$5] from CAVE Inc, 1/2 Fast Road, Ritner, KY
42639.

a½) Optionally, a durable plastic circular protractor and tenths of an inch &
millimeters ruler for another two bux [$2],

a-) If you are in a hurry, or are a cheapskate, you can make do the first time
with a schoolchild's semicircular protractor, a ruler, and any lined paper.

b) Pencil and paper,

c) Calculator. A common calculator makes the arithmetic a lot easier, tho you
could do it by hand if you like. If you don't own a calculator, I suggest that
you purchase one. They cost between $2 and $10 and are available almost
everywhere. The most significant difference between varieties is the quality
of the key pad. Everybody skip the fancy math the first time. I find a hand
calculator to be a lot more useful than a pop up "calculator" on a computer.  I
personally use a Sharp EL-510S (solar) and a Sharp EL-506A (battery).

You will not need:

a) Any land,

b) Any land description,

c) Any assistant,

d) Nor to leave the comfort and safety of your kitchen.

e) You don't even need this computer, except to make a printout so that these
instructions can be doodled with a pencil.

Normally I have students plot the map using the Silva Ranger compass as the
protractor. This develops familiarity with the compass and thus makes its use
in the field easier.  This compass costs $41 + $5 shipping & handling, which is
why you will use a circular protractor for learning.  If you have a Silva
Ranger, then use the instructions in the regular Chapter 1.


 SIY1_C.TXT     Plot a Map from a Land Description the Cheapie Way          10


A survey station consists of some point with an individual name and location.
The survey station may be located on the land, in a land description, or on a
map.

Survey stations on the land or on a map are connected together with lines,
similar to a "Connect-the-Dots" puzzle. These survey stations may or may not
be corners of the property. Survey stations in a land description are
connected by a set of instructions telling you how to find the next station.














                             TABLE 1

Line   Station   Station   COMPASS   TAPE         Comments
       TO        FROM      degrees   feet

1      0         0         0         0            You gotta start somewhere!

2      1         0         40        200

3      2         1         122       170

4      3         2         193       224

5      4         3         305       271          This is supposed to be the
                                                  same as station 0










 SIY1_C.TXT     Plot a Map from a Land Description the Cheapie Way          11

Look at Table 1.  The station is named "0".  This is the station TO which you
are surveying.  The station FROM which you are surveying is also named "0".
The station refers to itself.

The COMPASS direction to TO from FROM is 0.  A fancy name for the compass
direction is AZIMUTH.  The TAPE distance is also 0.

Each station must refer to either some previous station or be given some
arbitrary location. Be sure that you start someplace. The best directions in
the world are worthless if you don't know where to start.  Have you ever asked
for directions in Rural America? If so, you know about directions which start
at no where. Convert to now here.

When you get around to using CAVEMAP1.BAS you will find Graph 1 there. Or you
could register this disk and I'll send you the graphs.  Meanwhile, any piece of
lined paper can be used. Draw an arrow along one of the lines and write an "N"
near it. My graph has cheater lines on it, but they are not necessary.

Turn the graph paper so that the North Arrow points up.  Away.  To the top.
Unless there is some very good reason not to do so, always put North at the top
of your map.  This cartographic standard makes it much easier to keep the map
orientation fresh in your feeble little mind.  You will learn to *!HATE!* maps
with North in any other direction.

Station 0 is plotted as the little "x" labeled "0" on my paper Graph 1.

Line 2 of Table 1.  The station TO is named "1".  The station FROM is named
"0".  The compass direction is 40.  Lay the circular protractor on the map.
Turn the protractor so that "N" points North.  Slide the protractor around
until you can see [If you don't have Graph 1, then you won't see it until you
make it!] the "x" which marks station 0 thru the center hole.  Twist the
protractor until the N-S line on the protractor aligns with the lines on the
map.  The 40 degree compass direction lies in the direction marked "40" on the
protractor.

Make a mark on your graph at the 40 degree direction.  Use a straight edge to
draw a straight line from the "x" marking station 0 to and thru the mark you
just made marking the 40 degree direction.  Now use your ruler to measure off
200 feet [at the scale of 100 feet per inch] along the 40 degree direction.
That will be two full inches.  Now put an "x" at this point and label it "1".
Ain't this easy?!

If you can do it once, then you can do it twice.  On to Line 3 of Table 1.  The
TO station is 2.  The FROM station is 1.  The way to get to TO from FROM is to
go in a COMPASS direction of 122 degrees from North for a TAPE distance of 170
feet.


 SIY1_C.TXT     Plot a Map from a Land Description the Cheapie Way          12

Put your circular protractor on the map with the "N" end pointing the same way
as the North Arrow in the map.  Slide it until you can see station 1 thru the
peephole.  Precisely align the N-S line on the protractor with the lines on the
map, and place the center of the protractor precisely over the station.  Mark
the map along the 122 degree direction.  Remove your protractor and draw a
straight line along the 122 degree direction.  Measure off 170 feet with the
100 feet per inch ruler and mark the station.  Label it "2".

This is easier done than said.  On to line 4.  These are the instructions to
locate station 3.  Plot and label station 3.  Hopefully this is still easy.  If
you can do it thrice, then you can do it forever.  Or however long it takes to
get the job done.

Plot line 5.  Station 4 should be at the same place as station 0.  Or at least
too close to call them different.  If there is more than about 20 feet [that's
really 20 hundredths of an inch] between them, try it again.

If you have already tried it again, then give it up for a few days.  You have
blundered.  Your blunder should be obvious in hindsight.  If it is already a
few days later and you are still making the same mistake, then perhaps it is
hopeless.  You can send me back my instruments and instructions, and I'll send
you your dollars back.  Be sure to enclose the maps which you have tried to
draw so that I can improve my instructions.

Or just send me copies of your maps and whatever else you have done, and I'll
straighten you out.  If you have an idea of what went wrong, then make a note
of it.  Dave Beiter, CAVE Inc, 1/2 Fast Road, Ritner, KY 42639.  606/376-3137.

Everybody else now knows how to plot a map.

The CLOSURE ERROR is the distance on the map between two stations which are
supposed to be in the same place.  It is a check on the precision of your work,
and by implication, its accuracy.

Precision is like getting all the bullets in the same hole while target
shooting.  You have a steady hand, or a good shooting rest.  Accuracy is
getting them onto the proper target and evenly distributed around bulls eye.
Your rifle is properly sighted in.

The closure error is best thought of as a percentage of the run.  The RUN is
the distance which you have surveyed around a loop until you used the same
station location again for a closing station.  Just add up all the tape
distances.  The run for the map of the land description in Table 1 is 865 feet.

Measure the distance between station 0 and station 4 on your map.  Divide this
by 865 and push the % key.  If you have no distance between the stations, then
you have 0.0% closure error.  Congratulations.

 SIY1_C.TXT     Plot a Map from a Land Description the Cheapie Way          13

                                    Table 2

Line   Station   Station   COMPASS   TAPE         Comments
       TO        FROM      quadrants poles

1      10        10        0         0            Stone in Speed's line

2      11        10        S72E      293 3/4      Two white oaks

3      12        11        N37E      123          Corner with Davis & Green

4      13        12        N87W      352          Dogwood in Green's line

5      14        13        S3W       23           The beginning corner


Table 2 is the land description of a real parcel of land in Kentucky.  The
compass is recorded in quadrants and the distance is in poles.  This is the
common notation in Kentucky.  It keeps the landowners stupid.

The best way to handle the oddball units of measure is to convert them to the
familiar common units.  Change the quadrant notation to the 360 degree notation
and understand where you are going.  What the quadrant notation means is to
face the first direction.  Then turn the given number of degrees towards the
second direction.  You can plot this with a semicircular schoolchild's
protractor, but that won't teach you how to survey land.

Look at Table 2, Line 2.  The COMPASS direction is S72E.  What this means is to
face South, then turn 72 degrees towards the East.  Look at your circular
protractor.  South is 180 degrees.  Now count off 72 degrees around towards the
east.  You will wind up at 108 if you do it correctly.  If you have your
calculator, or are old enuf to be able to subtract with a pencil, then you can
simply subtract 72 from 180 and get that 108.

To translate quadrants to degrees, use the following rules:

If the compass direction is a cardinal direction (N, E, S, or W), then
   translate to ([0 or 360], 90, 180, or 270).

If a direction is within a quadrant, then do the following with the number of
   degrees within the quadrant:

   If the quadrant is NE, then add the degrees to 0.

   If the quadrant is SE, then subtract the degrees from 180.

   If the quadrant is SW, then add the degrees to 180.

 SIY1_C.TXT     Plot a Map from a Land Description the Cheapie Way          14

   If the quadrant is NW, then subtract the degrees from 360.

To translate your normal compass direction (azimuth) into the quadrant system,
use the following rules:

   If the direction is a cardinal direction ([0 or 360], 90, 180, or 270) then
   translate to (N, E, S, or W).

   If the compass direction is greater than 0 and less than 90, then the
   degrees are correct and the quadrant is NE.

   If the compass direction is greater than 90 and less than 180, then subtract
   the degrees from 180, and the quadrant is SE.

   If the compass direction is greater than 180 and less than 270, then
   subtract 180 from the degrees, and the quadrant is SW.

   If the compass direction is greater than 270 and less than 360, then
   subtract the degrees from 360, and the quadrant is NW.

Believe me, the quadrant system made a lot of sense in Antiquity (B. C.,
Before Calculators) when the arithmetic was done by hand.  Today its only use
today is to confuse those who would survey it themselves.

A pole is the same as a rod, is the same as a perch.  Still confused?  That's
16.5 feet in the English system of measurement.

To plot a map at the scale of 100 poles to the inch, you could make a new ruler
labeled so that each tenth of an inch equals 10 poles.  Each inch is 100
poles.  Or you can use your old 100 feet per inch ruler and mentally change the
scale from feet to poles.

Typical Kentucky land corners are identified under comments.

Translate the compass directions and plot a map of this property.  Plot it on
the same graph paper as you used before.  Draw a North Arrow pointing towards
the top of the paper.  Note the scale; "100 poles per inch".  Start where I
have marked an "x" and labeled it "10".

When I plotted a map of the data of Table 2, I really couldn't see any closure
error.  Calculating with a hand calculator, I determined the closure error to
be 3.0 poles, or 0.4%.  The direction to station 0 from station 4 is 293
degrees.  Compare this with the closure error of your plot.  Remember, the
percent closure error is the map measured distance between the two stations
representing the same location on the ground, divided by the run around the
surveyed loop, times 100%.  You should come out with a closure error of less
than 2%.  Anything more is blunder.

 SIY1_C.TXT     Plot a Map from a Land Description the Cheapie Way          15

A bit more about blunder and error.  Error is a small difference of opinion
which sneaks into measurements.  This is due to the unfortunate fact that the
real world isn't mathematically perfect.

Error is a part of this method, as it is with all real measurements.  So far
you have made errors in placing the exact center of the protractor over the
station, in aligning the protractor with the lines on the graph paper, in
getting the mark exactly at the proper degree, in placing the straightedge so
that the direction line goes exactly thru the from station and the direction
mark, in placing your distance ruler with 0 exactly over the station, in
guesstimating where some distance such as 293 3/4 really is on the ruler, and
in getting the station mark exactly where you want it.  And the protractor and
ruler have error in their manufacture.  Plus a few more errors that I haven't
thought of yet.

You can never eliminate all the errors.  Just realize that they are there, and
manage them.






Blunders are the *BIG* mistakes.  The most common blunder in surveying is to
read the wrong end of the compass.  You are going just exactly bassackwards
from where you think you are going.  Blunders are obvious when you notice
them.  When eliminated, they are gone completely.  Except that friends keep
reminding you of the time when you surveyed for half a day before realizing
that your compass was always pointing toward your new belt axe!

Blunders, by definition, are big enuf to catch and cure.  Always be sure that
your work has built-in blunder traps.  When they are not caught, little blunders
become BIG ERRORS.















 SIY1_C.TXT     Plot a Map from a Land Description the Cheapie Way          16

                                    Table 3


TO     FROM      COMPASS   TAPE                   COMMENTS

20     20        0         0

21     20        122       127 feet

22     21        8         169 feet

23     22        3         103 feet

24     23        86        211 feet

25     24        92        174 feet


26     25        S15E      12 poles

27     26        S14E      5 rods 7 links

28     27        S86W      7 poles 5 links

29     28        S2E       1 chain 32 links

30     29        S86W      13 rods 13 links


31     30        N4W       6 poles 1.5 links

32     31        N8E       3 perches

33     32        278       245 feet               supposed to close on 20

34     33        237       15 feet                closes on 20


Table 3 gives you some more practice in plotting a map.  Note that the
direction and distance units vary.  Translate all of this to into degrees and
feet.  Plot a map from this land description.

What sort of closure error did you get?  What is this in terms of percent
closure error?  Is this an acceptable closure error?  The actual calculated
closure error is 0.00%.  Station 33 was supposed to be the closing station as I
produced these data.  The distance for station 34 is my closure error when hand
plotting the map.  My hand plotting error was 0.8%, which I consider to be
excessive.  That's why I use a computer.  And the computer is easier too.
 SIY1_C.TXT     Plot a Map from a Land Description the Cheapie Way          17

Take another look at your map.  The closure error should be quite small.  Now
look at the boundary of the parcel and think about it.  Is it possible to make
a blunder and still have a small closure error?  Possible, but not probable.

You are now ready to plot a map of whatever interests you.  You may need to
translate the land description into the proper format to plot. Some units of
distance which you may encounter are: a pole or a perch or a rod, 16.5 feet; a
rope, 20 feet; a chain, 66 feet; a link, [a hundredth chain] 0.66 feet; a
furlong, (ten chains) 660 feet; a yard, 3.00 feet; a meter, 3.28 feet; la vara,
2.78 feet (Texas, variable).

If your map comes out too tiny, or if it won't fit on the paper, then you will
have to change the scale of your map.  A square plot containing 10 acres has
the length of each side exactly one furlong, or 660 feet.  At a scale of 100
feet per inch, the map of that 10 acre square would be 6.6 inches square.  This
fits nicely on the graph paper.  You might want to plot on a few different
scales just to see what happens.  If you run off the graph paper, you can add
another piece to that side.  Line up the grid lines.  Mark how the two sheets
connect, or tape them together.

You can obtain a copy of the deed for a parcel of land by visiting your
Recorder of Deeds, or whatever title s\he holds in your county.  Just walk into
the courthouse and ask for deeds.

You will need help finding what you want, so ask.  The deeds are indexed in
various ways, depending upon where you are.  In Wayne County Kentucky, deeds
are indexed alphabetically by date. Really! I said that you would need help!

To actually survey land, you will need different instruments.  The protractor
will be replaced with a compass.  I use the Silva Ranger type 15 compass for
all of my surveying work.  It is comparatively cheap ($41 + $5 shipping &
handling), precise to about one degree (the same as your hand plots), fits in
your pocket, and is nearly indestructible.  Anyone can quickly learn to take
good compass directions with it.

You may already have a compass sufficient to survey it yourself.  The Brunton
pocket transit is also known as the Army Artillery compass.  These are commonly
available in Army surplus stores, after having been dropped by an excited
soldier.  They can be rebuilt for approximately $50.  They are slower, more
difficult to use, much more delicate, and more expensive than the Silva Ranger,
but if you have it, use it.

A lensatic compass, also known as an Army marching compass, is not sufficient.
This fine product of the American military-industrial complex was diabolically
engineered.  Without eight weeks of Basic Training in the use of the
bassackwards scale, you are sure to get lost with it.  Should The Enemy attempt
to use one of these marching compasses, he would immediately become completely
disoriented.  He couldn't even find his way back from the latrine with it.
Leave your lensatic marching compass in the latrine where it belongs.
 SIY1_C.TXT     Plot a Map from a Land Description the Cheapie Way          18

A Boy Scout compass, a car compass, a "survival knife" compass, or other such
compasses are not capable of being read to a sufficient precision.  There are
several other types of compass which are capable of a one degree precision.  If
you think that you might have one of these, ask.

The ruler will be replaced by a tape measure.  A 200 foot fiberglass and PVC
surveyor's tape costs $27 + $5 shipping & handling.  You can get away with
using a carpenters tape measure if you are careful not to snag or step on it.
It's nice to get more than 12 feet in a shot, too!  A steel tape will work
until somebody steps on it.  And you might not want to be holding onto the end
of a 200 foot lightning rod.

If you have any problems, comments, criticisms, or corrections, contact:

Dave Beiter
CAVE Inc
1/2 Fast Road
Ritner, KY 42639

606/376-3137