Finding survey pins

I was thinking I'd like to have an idea where my survey pins are. I've found a couple by luck. I thought I should be able to use the directions from the survey map to go from the found pin to the next pin on the map. However, I don't understand the directions on the map. It will show the distance between the 2 pins above the line & the direction of the line below it. An example of the direction is N 50'56'14" W. I was looking for some kind of degree, like 200 degrees ne or something. Can that be converted to degrees somehow? Is there someway of using that info w/ a compass or a gps to find the next pin? I've never used a gps, but it seems there should be a way to put in a distance & direction so it would lead you to the next pin. I know they aren't 100% accurate, but would think you could get close it. I'm not putting up fence or anything. I just bought some acreage that connects to what I had & would like to know about where my lines are.

The survey info is a method called "metes and bounds" that is used for most if not all of the US. The way it works is you stand at the pin or other reference point, like a section post, and face the direction of the 1st piece of data ( N or North in your case). Then swing your transit (or arm) and point in the next direction given (50 deg to the West in your case), with 0 being straight ahead or North and 90 deg being dead to your left. Then measure along that line the distance for that "leg" of your property line. Depending upon how good your compass and transit are, you should get close enough to find the iron (if it's not buried and the surface marker gone). I used a construction transit to mark the correct position of a survey stake that a neighbor moved (long story) and then at the insistence of the neighbor had it resurveyed. I was within an inch of the surveyors position.

If you can somehow setup a reference with your existing property lines, then a compass may not be necessary, but a transit will.
OR....
you could always setup some reference lines (off of your known property line) using a 3-4-5 right triangle and use trig to calculate how far off the the 50 deg 56' 14'' is from the reference line. Best to do this on paper first.

Accuracy will also depend if you've got clear sight lines, forest to tramp through, etc.

N 50'56'14" W

That is a direction in degrees, minutes and seconds. [img]/forums/images/icons/grin.gif[/img]

Egon [img]/forums/images/icons/grin.gif[/img]

Agreed with JML755 post deleted.

jimbrown,
I disagree on your diagram of the OP's property description. It is NOT a NNE line. The bearing was N 50'56'14" <font color="red"> </font color> W. <font color="black"> </font color> This means it is a NNW line, with the bearing measured in a CCW direction from the pin and North (0 degrees) towards due West (90 degrees). Check out the definition of metes and bounds (http://en.wikipedia.org/wiki/Metes_and_bounds). And for what he's trying to do (without surveyors equipment) the 14 seconds (and probably) 56 minutes would be useless.

The direction will be 50 degrees 56 minutes 14 seconds west of north. [img]/forums/images/icons/grin.gif[/img]

Subtract from 360 and you should have a compass bearing of approximately 309 degrees. [img]/forums/images/icons/grin.gif[/img]

Egon [img]/forums/images/icons/grin.gif[/img]

Well, now I know why surveys are so expensive. Most of that goes over my head. I was thinking of using one of those handheld gps units to try to find the next pin &amp; then just going pin to pin. I haven't used one before, so I don't know if it will work. If i'm following at all, it seems you just get your direction from the N &amp; the W to be NW. Then subtract the first # from 360 for the degree. Then walk in that direction at that degree for the distance of the line. If it don't work, it will be a nice hike anyway.

Then subtract the first # from 360 for the degree. Then walk in that direction at that degree for the distance

Nope, doing the subtracting gives you a compass heading. A compass heading is in degrees and is not dependent on any other direction than true north for the compass to which the compass needle is adjusted after you set it for the declination of your local area. [img]/forums/images/icons/grin.gif[/img]

Egon [img]/forums/images/icons/grin.gif[/img]

N 50'56'14" W = 50degrees 56minutes 14 seconds North of West.

50 degrees + 56 minutes * (1 degree/60minutes)
+ 14 seconds * (1 degree/3600seconds)
= 50.9372 decimal degrees

So start from that point with a compass and sight
a hair less than 51 degrees north of west.
Facing directly west it would be 51 degrees to your right.

Pooh Bear

I appreciate the help. I think I'm starting to get it now. If I'm traveling the right degree, then that means I'm going the right direction. I'm gonna try to borrow a metal detector to help find the pin once I'm in the right general area. I have one last question though. Some of the pins are over 1000 feet apart. I've been looking at the Garmin Etrex series gps. Can you input a direction &amp; distance so it will lead you to the right place? I've talked to a few of the sales people, but none really seem to know much about it.

In case Egon hasn't sufficiently confused you... let me take a hack at it.

Can dead men vote twice?

Can - - - - -(C) Compass
Dead - - - - (D) Deviation
Men - - - - -(M) Magnetic
Vote - - - - (V) Variation
Twice - - - -(T) True

There is true north which varies little and can be assumed constant for your purposes. The compass does not give true north. The compass, strictly speaking, does not give magnetic north either.

The mathematical difference between true north and magnetic north is called Variation and variation can and often does vary from location to location. At any given location variation is typically sufficiently constant to be assumed so.

There is also a difference between magnetic headings and compass readings which is called deviation. Deviation may be negligible with your compass use, especially if little or no ferromagnetic substances or electric currents are close to the compass. Try to read your compass while it is NOT NEAR iron, steel, nickle, electric devices, magnets, etc.

A good hand held GPS will typically get you to within several feet (low double digits) of a specific point. Depending on the features of your GPS it may or may not give you a readout of distance and bearing to a reference point or otherwise be useful for your task.

Surveyors use GPS units with temporarily stationed fixed location auxiliary equipment and can get accuracies to within a fraction of an inch. No commercial off the shelf consumer grade units will get even close to that. The best most GPS can do is to deliver good repeatability, i.e. bring you back really close to the same point once that point has been registered by the unit. Absolute accuracy is less. The ability to take you to a specific spot via lat and lon is less accurate than the ability to return you to a spot.

An engineer's compass (style of instrument) is the minimum instrument to use to try to follow metes and bounds. That in concert with a good 300 ft tape should git 'er done if your sight lines are not obscured in heavy brush, timber, or by topography.

Pat

</font><blockquote><font class="small">In reply to:</font><hr />
So start from that point with a compass and sight
a hair less than 51 degrees north of west.

[/ QUOTE ]

Sorry, that will not work.

With the heading given you have to start from true north and then go the 51??? to the west. [img]/forums/images/icons/grin.gif[/img]

Pooh bear, if the heading had been written as W51 degrees N then you would be correct. [img]/forums/images/icons/grin.gif[/img]

</font><blockquote><font class="small">In reply to:</font><hr />
There is also a difference between magnetic headings and compass readings which is called deviation.

[/ QUOTE ]

This should show up on topographic maps as Declination. [img]/forums/images/icons/grin.gif[/img]

Egon [img]/forums/images/icons/grin.gif[/img]

Right you are Egon. Don't you just hate having to disambiguate overloaded identifiers?

Pat

Well how about SSE or WNW all parts of the compass ??? whatchya macallits! [ Rose maybe] [img]/forums/images/icons/grin.gif[/img]

AlBald1:
in your case set the declination for your on your compass. Then figure out your compass heading and using that pace off the distance if looking for an established pin. When near the proper area start looking around. In most cases it will help to have help. Get the helper out ahead and the get them to stand on the line as shown by your compass heading. Then you go stand in their spot and repeat the procedure and on and on. [img]/forums/images/icons/grin.gif[/img]

What's this about swinging a compass Pat?? [img]/forums/images/icons/grin.gif[/img]

Egon [img]/forums/images/icons/grin.gif[/img]

Oh yes!!! Declination is a source of confusion for some of us since the angle the earth's magnetic flux lines make with a horizontal plane normal to the earth's surface "could be" called declination but the topo map's use of the term is to indicate a horizontal variance not a vertical one.

Not to worry though, even though a compass needle suspended such that it can pivot vertically as well as horizontally will still, via its vertical projection, indicate the proper horizontal component of the earth's magnetic field.

Again, I do not like overloaded identifiers that require disambiguation, as often in normal discourse confusion results far easier than recognizing another's use of terminology to be in variance with our own.

Pat

Egon, I can swing it or box it.

Pat

Ok, then I got a question about my own survey pins.
Last summer I calculated a heading of 4.94dd S of E.
Should I have used 4.94dd E of S instead?

A neighbor put a fence up and I suspected it was in the wrong place.
But 4.94dd S of E showed it in the right place.
But if it should really be 4.94dd E of S then it is way off.

But it looks right the way it is according to the survey map.
All my angles came out right when I drew it up in AutoCad.
I took the survey map and recalculated it to decimal degrees (dd).
So now I'm real confuzzled.

I just drew it up again in AutoCad using 4.94dd E of S and
there is no way that could be correct.

I'll have to get the original survey map to check my figures.

Pooh Bear

http://i35.tinypic.com/34efdir.jpg

The line from the left comes down the center of a dry ditch.
On the end of that one line is 4.94dd S of E and the other
line is 4.94dd E of S. My neighbor would pitch a fit if I tried
to put a fence up on a heading 4.94 E of S.

Panorama view of my house with aerial views and maps

Given a survey heading of say;

N50degreesE

Then the first direction set would be north and the angle would be 50 degrees to the east.

W50degreesS:

First direction would be west then 50 degrees south of west.

Or so I recall the system.

Egon [img]/forums/images/icons/grin.gif[/img]
[img]/forums/images/icons/grin.gif[/img] [img]/forums/images/icons/grin.gif[/img]

Pooh, Very nice presentation. I hope your property is safe from flooding in case Al Gore's Revenge is unleashed up stream of you .

What application software did you use to stitch the pans together? I typically eschew Photoshop and anything at all complicated and just go super simple, IrfanView.

Again, nice presentation.

Around here the surveyors use a metal detector to find buried rods (typically rebar.)

Pat

I used MS Paint to put the pictures together.
Yep, if it can't be done with Paint or Irfanview then I don't do it.

My parents house next door has been completely surrounded
by flood water but it stayed just below the wood floor joists.
Flood of 2003
My house is out of the flood plain of the river.

Pooh Bear