Yah. The old coordinate system is throwing me for a loop. The angle is
"supposed to be" ~~ 8.3° east. However, the quarter section corners are
well known, and the actual angle from the SE corner to the NE corner
comes to ~~ 7.4° east. However, the easement description says 8.3°
(along the boundary). So I just faithfully followed the angle called out
in the easement description, and ended up 12 feet east of the actual
boundary line. It can't be there, because that's not even on the same
quarter section.
What do surveyors do in a case like this? All the internal angles are
going to end up off by about 1° too (or are they?). Crazyness.
The road built on the easement has been in place for almost 50 years. A
sane person would re-pin all the corners of the easement along the
centerline of the road, and move on, because the description of the
road/easement do not match. The errors I see between what's described in
the survey documents and what is on the ground vary by between 30 and 60
feet.
I'm sure part of it is because the terrain is extremely tough. Slopes of
100%, and lots of trees. I have no clue how they did the original survey
in 1970. Today, you can GPS almost any point you want/need.
bp
<part15sbs{at}gmail{dot}com>
On 11/27/2016 10:49 AM, Chuck McCown wrote:
Oh, OK, yeah, totally forget geocodes when doing metes and bounds.
All the datum conversions etc prove to be worthless when trying to be
very precise.
And most section lines are not true NWES and most section lines are
not one mile either. Sometimes you luck out with an exact mile lying
on one of the ordinate directions but that is infrequent.
You have to use physical monuments and the DMS lines of the metes and
bounds. Frequently they are in that old "N 12 deg 3 min 2 sec E" format.
I just go through and convert all the angles to Cartesian angles
first and then start laying down lines in the drafting program. Or in
google earth. You can describe a line/path with a bearing and distance
in GE.
-----Original Message----- From: Bill Prince
Sent: Sunday, November 27, 2016 11:35 AM
To: af@afmug.com
Subject: Re: [AFMUG] Converting vectors to a shape (.SHP) file?
The easement starts at the eastern boundary of the quarter section
(which is not true north south; a little over 8° east). According to the
description it is supposed to be on that line at a certain distance from
the corner.
When I drew it on GE, I just measured that distance on that line, and it
actually comes out 35' north of where the road actually got laid. No big
deal, the easement is 60' wide, so it mostly fits.
However, when I used this tool to get a lat/lon, the point is about 12'
to the east of the point I measured. Now I know that drawing something
like this in GE is somewhat error prone, but I did not expect it to be
this far off.
bp
<part15sbs{at}gmail{dot}com>
On 11/27/2016 10:28 AM, Chuck McCown wrote:
The easements I do are totally desk top, no survey. But I do have the
recorded metes and bounds of the property to go by and generally use
its boundary. But my point is, easements are generally a lot more
loose than a property description used on a deed. I am not surprised
that you may find a significant error. After all, the easement was
just to get the landowner to allow something to be put there. If it
is a public utility company and it gets contested they will just file
a quiet title action and get it corrected due to having the right of
eminent domain.
Have you compared the metes and bounds of the easement with the
parcel boundaries or is it just heading cross country through the
middle of a parcel?
-----Original Message----- From: Bill Prince
Sent: Sunday, November 27, 2016 11:17 AM
To: af@afmug.com
Subject: Re: [AFMUG] Converting vectors to a shape (.SHP) file?
This is actually for an easement, and it's open on both ends. It does
start at the corner of a quarter section, but from there it's just a
zig-zag line. Internal coordinates are unknown.
To make it more complicated, the original coordinates are based on the
"California Coordinate System, zone III", which was derived using NAD27.
So I had to convert those CCS-zone III, to NAD27 (lat/lon), then to
NAD83 (lat/lon), and then to WGS84 to get something close to something I
can use with GE.
I did convert the first vector, and it appears to be off by about 12'.
Something stinks...
bp
<part15sbs{at}gmail{dot}com>
On 11/27/2016 10:01 AM, Chuck McCown wrote:
I do this on a regular basis for easement work. There is a nice
range/township/section overlay you can buy for GE so you can at
least find the section corners. Most metes and bounds use a section
corner or a quarter corner as the point of beginning. If a parcel
is complex, I actually lay it out in solidworks, my 3D mechanical
design program, that way I can just directly enter the angle
directions and distances. And the parcel almost always closes. You
could do that with any drafting program most likely.
Then I export that to an image and import the image into GE. Stretch
and rotate to fit the visible landmarks and monuments.
There will always be an error in closing unless they wind up with a
"more or less" to point of beginning. That takes all the slop out.
-----Original Message----- From: Bill Prince
Sent: Sunday, November 27, 2016 10:49 AM
To: af@afmug.com
Subject: Re: [AFMUG] Converting vectors to a shape (.SHP) file?
The vectors describe a property line, and start at a fixed WGS84
coordinate. Then it's a series of distances and azimuths from there. I
tried drawing them with GE, but there is an accumulation of small
errors. There are about 10 vectors total.
Something like starting at point lat/lon, go 700 feet azimuth 8° 27'
42", then 200 feet azimuth 27° 15' 08", and so on.
bp
<part15sbs{at}gmail{dot}com>
On 11/27/2016 9:13 AM, Chuck McCown wrote:
Is the end result displaying your vectors on GE? If so there are
ways to just import them as a text file.
I did it, don't recall how, perhaps I used some kind of app but in
the end, it was easy. I may have just drawn a line and then
reverse engineered the KMZ or KML file.
-----Original Message----- From: Bill Prince
Sent: Sunday, November 27, 2016 8:58 AM
To: Motorola III
Subject: [AFMUG] Converting vectors to a shape (.SHP) file?
I have a boundary between parcels that is described as a series of
vectors (distance & bearing) from one point. Apparently this can be
imported into Google earth as a shape file (.SHP extension). I have
been
looking for, but not finding a tool that allows me to enter the
vectors
in text, and spit out the .SHP file. Does anyone know where I might
find
this?
