GPS for measuring and platting?

[MNBobcat]

Hi All,

I've been doing some googling but so far no luck. I know someone here will have some suggestions.

I have about a 12 - 15 acre field in which I'm going to be installing deer exclusion fencing and then a vineyard. I am interested in (I assume) a GPS device that I could use to, for example, locate the 4 corners of my fence. Basically, to help with laying out where things need to go.

I know surveyors have those sorts of things and I hear they are terribly expensive pieces of equipment. Don't really want to hire a surveyor if I have other choices. I'm wondering if there isn't some kind of hand held GPS or the like that would allow me to do it myself? Anyone have any ideas/suggestions?

Thanks!

 

[mddorange]

Some people say that you can use an app on a smartphone.

 

[MNBobcat]

Some people say that you can use an app on a smartphone.

I found an iphone app but the GPS on the iphone is only accurate to about 15 feet.

 

[NWOutlawMX]

I'm going through this same thing and have searched for hours. There really are no truly accurate, cheap units. The big question is if any of the fence lines are on a property line? In my situation I am getting ready to put a 18' access gate to my property. I only have an easement for 25' so with the pillars I have no room for error. I checked the county maps and previous surveys looking for the corner monument that was supposed to be set in '98 to no avail. Even rented a metal detector looking for the pin with no luck, so I was out of options.

I called a local surveyor and he quoted me $400 to find the corner and update the monument and mark off 50' down the property line. One thing to keep in mind also is when they provide the service they are also required to file it with the county so you now have you're property line on record and if the neighbor tries to contest the line, they would be able to defend you in court. Note - Surveyors can't decide property disputes, only the court can do that, but if you have a licensed surveyor odds are good you'll get sided with.

Here's an example that's happening around here - a couple bought some property next to an existing land owner and because of a feature of the terrain or something they asked if they could use the corner as an access or get some sort of easement or agreement. The landowner was evidently extremely rude and declined. There must have been something already there or some reason they suspected they had a right to the section in question so they went and hired a surveyor. Turns out the existing property line was incorrect and half of the existing landowners barn and garage are over the line. They are still tied up in court but he's going to have to remove the portions over the line.

IMO - If you're going to invest in a fence and vineyard, might as well invest in making sure it gets to stay there.

 

[Redneck in training]

You can get a GPS with WAAS that is at best condition (unobstructed view of sky and WAAS transmitter nearby) precise to about 3ft of absolute error. Assuming that the error is about the same for all corners and averaging several measurement you might get reasonable good results.
If you can see all four corners then you can use surveyor transit (optical device). It will let you measure or set horizontal angles. So with some simple trigonometry you could place the corners with pretty good precision.

 

[treefarmerguy]

Gps will give you latitude and longitude. Most old deeds will list only compass bearings. I've had good lock with a sighting compass which can be found at Forestry Suppliers or Ben Meadows.

 

[Deerherd]

For what you describe, there is an App for that. As long as you aren't trying to locate actual lot lines or crowding a border, these work very well.

The one I use is Measure Map. I have attached a screenshot of a quick outline in a field. A guy who does roofing estimates turned me on to it and it's a great app for any business that needs to estimate areas.

 

[MNBobcat]

My property is all surveyed and I know where the markers are. The fence will be set about 15 feet inside the property line. Mostly what I want to be able to do is mark locations of things fairly accurately. So for example, my fence corners will need to be so many feet apart as I have fixed amounts of wire fencing. I can roll the distance with a wheel but its a lot f messing around to get things square. Would love to be able to look at a display amd walk to the point where I need to be. Accuracy on the vineyard is more important than the fence.

I'll do some reading on the GPS with WAAS. Thanks!

 

[/pine]

You can rent a theodolite that can find Mag. N on it's own...if you have a plat and can find and set the instrument up over a known corner monument etc...the instrument will do everything you want and the newest ones will give you GPS coordinates for anywhere along any of the lines...

You might see if you can rent an instrument that comes with a laptop that has all the software installed to do a "closure" from just one position if the terrain is fairly flat...

One caveat...:
Many times the angles (deg./min./sec...) marked on property plats are vectors and not bearings...

 

[newbury]

Like /pine wrote. See if you can rent a handheld survey unit.
In

at the 36 second 50 second, 1 minute 50 second you'll see a guy holding a "Contour". This hooked into a laptop and gave VERY precise measurements.

I used to train soldiers to use these, very simple, about an hour lesson. We used them primarily for mapping minefields in Iraq and Afghanistan.

Undoubtedly there are similar cheaper units now.

As an aside when we used the Contour beside a road in our training sessions we would invariably get someone slamming on the brakes because they thought we were running a speed trap.

 

[bdog]

Where are you located? I have a survey grade GPS and would be willing to help you for some barley pops if you are close by.

We recently built a 25'x50' equipment shed with six vertical columns. I placed the columns using the GPS and all were with in 1/2". It is an amazing tool. I have over 20k in it but we use it for work and it has paid for itself many times over.

 

[MNBobcat]

Where are you located? I have a survey grade GPS and would be willing to help you for some barley pops if you are close by.

We recently built a 25'x50' equipment shed with six vertical columns. I placed the columns using the GPS and all were with in 1/2". It is an amazing tool. I have over 20k in it but we use it for work and it has paid for itself many times over.

Hey Bdog,

That would have been sweet. Thanks for the offer! I live in Minnesota though. A little far for you to drive. I'd have certainly bought you some barley pops or given you some grapes or both!

Its amazing how accurate those GPS's are. I had heard they were accurate within about a half inch.

 

[Gary Fowler]

I would caution you against erecting your fence anywhere except on the property line. Those have a habit of becoming property lines after a few years then requiring another survey to straighten them out. If too many years pass it may even become impossible to rectify without extensive court cost unless the adjacent property owner is willing to just set it at survey line. We had that problem when we bought our present property. The fence line was up to 75 feet off the real line at one end. Luckily the property owner had no problem with us relocating the fence line. This did take some dozer work to clear 50+ years of timber growth.

 

[MNBobcat]

Gary,

No issues like that here. I'll be putting a road between the fence and the property line. In addition, I have the property line staked with PVC stakes about 4 feet out of the ground and painted red.

 

[oosik]

I have a Garmin hand held GPS. On a good day its accuracy will be +/- 10 feet. I've never seen a hand held anything that can match the accuracy of a tripod mounted Theodolite. But, then again, technology is one of those things that moves faster than my age.

As Gary Fowler said - fences erected "close" to property lines have a habit of BECOMING property lines with time. I don't think you want to have to defend an "inboard" set fence at a later date. Just move the fence on that side to the property line.

OR have an erected fence on the property line and the fence you want to instal and that each is separate, unique and easily identifiable.

 

[skylarkguy]

You might try checking with an engineering department at a local university. They might loan you a total station for all your survey needs.
Alternatively look into differential gps to increase the precision of your handheld unit.

 

[s219]

I found an iphone app but the GPS on the iphone is only accurate to about 15 feet.

I develop the "Theodolite" app for iPhone which is used for a lot of survey work. iPhones can get down to about 3 meter accuracy. You could buy a sub-meter GPS add-on for the iPhone (or iPad) for about $600 and get down to about 20 centimeter accuracy. However, it can take several minutes for the hardware to settle out to that level of accuracy. Me, I recommend using good old fashioned common sense, with a combination of the app, surveyor's tape, and Brunton pocket transit (great tool). Using those tools, I was able to survey quite a bit of our property and develop the site plan. The real surveyors where impressed I came within an inch on the foundation pins. I am of the opinion that surveying is more about technique than equipment. Multiple measurements can be used to reduce the error of any one tool.

Normally, if your property corners are marked, the app with onboard GPS can get you close enough to find the pin, and then it's a matter of shooting bearings to other corners where pins may not be available. Shooting bearings from two directions can let you triangulate a missing pin pretty well.

Good luck!

 

[RippySkippy]

I know you're on top of this. If you need a reason to "get it right" look up Adverse Possession and Minnesota state laws specifically.

 

[EddieWalker]

I've found that the first thing to do is clear the area you are going to be working on. Then I use a wheel to walk of the distances. It's accurate within a foot and when I put flags out, I can double check my measurements, or create an area and then measure off of it. Old School is sometimes still the fastest, easiest and most accurate. It's always the most affordable!!