GPS ???

gumbydamnit

I am looking to buy a GPS and have no idea of what brand or type, never messed with one. I want one to locat property corners and be able to set points so I can mark off straight line from point to point. Anybody have one they use for such a thing? Or does anyone have any suggestions as to what I could get. Do not want to spend a ton of money but do not want a pos either. I can research all day but would like to have some info from someone with hands on experience. Thanks............TOM

336marlin

I don't use one for that but use one of the handheld type on a regular basis. For locating property corners accurately you would need a very expensive system such as that used by surveyors that relies on differential beacons for mm accuracy. I've found the handheld devices such as made by Magellan and Garmin to be accurate to within (+/-) 6' when checked at known "monuments" as those set by USGS. They can be had for from $99 to $300. Used to be the average handhelds weren't very accurate; possibly (+/-) 45' but the government lifted a restriction on their signals years ago that increased the accuracy. Also, accuracy suffers under tree canopy and is confused by reflected signals among buildings. Garmin has worked at making their handheld units very user friendly.

mbsams

A portable, handheld GPS is not accurate enough for property bounderies. At best you will be +/- 15 feet or so and thats if you let it update for several minutes in one spot. Typically you will be +/- 10-15 meters. For an aproximation they are great. Special purpose and very very expensive systems can be accurate to the centimeter.

rsnyder55

Have you looked for the surveyors markers?

gunnut505

You don't need "beacons" or any of that hogwash to get a straight line 1100' long and be able to walk it.
You need to hire a surveyor to determine your land boundary because your neighbor will contest whatever you come up with. That's where you save money.
A surveyor will locate the township corners, section corners, or other surveying control and from your deed (or whatever your previous owner filed) will determine your true positions.
A surveyor does a very good job of resolving disputes with adjoining property owners by marking and locating your (and their) property corners relative to the township, parish or subdivision plats filed in the county clerks' office.
Or, you can estimate where you think you need to be, mark off 1100' in any random line, and make an angle (is it 90? could it be 84.53.15?) to your best guess, and then proceed to mark off another 1100'.
When you bought the place, a survey should have been included in your paperwork at closing. Find it and shop for a surveyor.

You could get a half-fast idea of your line by establishing a point on any old handheld GPS by turning it on over the point, waiting about 10 minutes, then store the point as "1". Go to the other end of the line (look for the survey cap/rod/rebar) and establish it as "2".
Now punch in goto "1", and walk in as straight a line as you are able, marking your progress every 50-100' with a stick, lath, flag, or some other mark you'll be able to see as you walk to "1". That's as half-fast as they get.

MBK

Good topic for GENERAL.

A Garmin handheld with maps will help you, they also do area calculations.

You can take corner readings then go to Google Earth and set those points, then draw lines for the distance.

gunnut505

US5840- You're talking about a Surveyor's Inspection Report, which is not a survey, but a rough drawing for the title company. You'd be foolish to rely upon a SIR to do anything but soak up coffee spills. It is only "good" for 90 days or so, and is not designed to be filed as a statement of boundary or ownership delineation. A Survey is a document that shows exactly where a piece of property is, the adjoinders, their lines' orientations, areas of the property concerned, what book and page the information was filed in at the county clerk's office or recorder's office, and which plats were used to determine those positions.
Anyone who buys a piece of property without getting it surveyed is either an idiot, or trusts his neighbors more than he should.
MBK- Google Earth is about 1500' off for position in my area (nM); and it is possibly worse in your area. Using Photo I.D.; pick a tree that you can actually visit and take a shot (establish a point/set of coordinates), then enter them into GE and see how far off you really are.
Gumby-Surveyors spend about $35K for the least expensive centimeter-level GPS receivers made by Trimble, Wild, Topcon, etc. and are able to determine positions to a resolution about the size of a spinning dime; any handheld will give you a set of numbers, but nobody knows just exactly how "good" they are without the software to crunch those numbers with.
Another possible solution would be to visit a pawnshop to find a used theodolite (surveying instrument that turns/measures angles) and tripod that you could set up on one of the points of your line, sight the other end, and start setting points in between. However, that line is only as good as the guy that set the points you use. You would also need to find an EDM (Electronic Distance Measuring device) and some reflectors to shoot distances with, or you could find (at that same pawnshop) a 300' surveyor's chain (tested and certified to be exactly 300', and each foot mark is exactly 1 foot) and have someone look through the theodolite to keep you on line while you measure the distance with the chain.

Basil_O

I agree with gunnut505. We've got a GPS system for measuring and setting property corners, mapping, and construction staking. Yep we've got at least $35K into it. Mind you that's for one crew. It's the cost of playing this game nowadays. If you want something to hold up when push comes to shove - hire a surveyor and have him prepare a plat of survey for you. If you want to do it the old fashion way, I can tell you this. I still have the "old line of sight" equipment and remember how to use it, but whenever I get it out to do some work, help that knows how to, cut brush, catch line, set a point, and measure ahead with and steel tape and plumb bobs is hard to find these days.

MBK

Dear GunNut,

I beta test for Delorme. I have tested my Google Earth Coordinates long ago and found them to agree with 2 GPS handhelds I own. I did this standing on a USGS Monument.

If you are 1500 feet off, I would sure like to see confirmation posted.

I never said using Google Earth to set boundaries was appropriate, but it is helpful for confirming fencelines and measuring.

The local county might have online GIS information that the OP might use to get recorded corners. In many parts of the West, an old fenceline establishes boundaries through adverse possession, open and notorious use. Getting a new survey doesn't change anything.

gunnut505

Try the little photo ID test in the earlier post; you may have been really lucky and chose one of the "pin" points used by GE to keep the photo and area aligned.
Old fencelines are not reliable indicators of anything; could have been a cross-fence to keep the cows out of the cornfield. They are also not used to establish boundaries; a surveyor uses deeds, section breakdowns, township breakdowns or other information to re-establish the original positions recorded at the county clerk or other recording authorities' offices.
GIS is nowhere near as accurate or reliable as centimeter-level survey quality equipment; that's why GIS outfits are only $500 or so and do only mapping-quality positioning.
Adverse Possession usually refers to easements or roads thru another's property, and sometimes, even with "open & notorious" use for 5 years do not revert to the user instead of the lawful owner.
Getting a new survey re-establishes the original; if there has been a subdivision of land nearby or on the property concerned, it could change everything.
I get my coords straight from NGS when I want to search out a monument or establish a baseline for a survey; if I use GE to find a photo ID point, I know there's going to be as much as 1500' difference between what GE gives and what the true coords are. Don't know how I'd be able to post the screen shot of my Garmin versus a screenshot of where I'm standing versus the true position of the point.
BTW-I've been a GPS surveyor since 1976; we used to have to go out in the middle of the night (when the SVs were visible) to occupy a position for several hours to receive enough data to be able to process a position for it. That took several observations on the same point on successive nights with another 2-3 units on other points simultaneously. Back then, we called it Doppler Surveying. Nowadays, almost anyone can claim to be a GPS surveyor if they have the dough to buy the gear and hire someone who knows how to use it properly. Then again, there's that pesky licensing thing.....