How to figure out property line over hills/woods

[beenthere]

I have a similar, although shorter, line fence problem (going over a hill) about 800'.

My plan is to pull a wire between the two known points, then lifting the wire at intervals using two posts fastened at the top, with a support wire hanging down. Like hanging the wire from a tripod (only it would be a bipod). Enough supports to get the wire hanging suspended and free from the ground. Then sighting and moving the legs of each bipod such that the support wire hangs plumb. Hope I described that well enough.
I will be stretching wire anyway, so figured this first wire would not be a useless effort or expense. The posts for the bipods would be, but figured 2x4's 8-10' long should do the job. Maybe a tripod of three posts is needed for stability. Its been on my mind for several years. So far the neighbor doesn't want a line fence. Our laws say the line fences must be shared. The right half of the line facing the neighbors property is mine to fence.

 

[archerm3]

are the survey writeups done in Magnetic north or True north?

 

[Josephm]

Beenthere, is there any way you could describe your method a little more? I am having a hard time visualizing what you have described.

Thanks,
Joseph

 

[dodge man]

I think I can picture it. Joesph, picture a tripod with a wire hanging below it. Than take the string line you want for your line and hang it from the wire below the tripod. This would allow it to hang free and give you the correct line. The problem is, if you have a 30' high hill, your tripod would have to be 30 feet high. At least thats my take on his idea, and it would work in theory if you can build the string line high enough.

 

[dmccarty]

Our north/south property lines are marked every 300 feet or so with a pin. I have those lines cleared and I mow them with the DR brush cutter a couple of times a year. This is in heavy woods.

Our east/west lines are another matter. Heavy woods and at best there is a pin every 800-900 feet. And somewhat hilly. Both my father and I have tried to use a compass to work a line through the heavy trees and brush. And we still are off quite a bit and all we are trying to do is clear a line not build a fence.

I am using a hand held GPS to do the same thing on another line and it is easier. All I want to do is get close to the line, there is old flagging up here and there in places, so I can clear the line of brush. Maybe just maybe I will be able to run string to really find the line.

But I doubt it. I have had the surveyors out to remark some lines in the past and it was worth every penny paid. I could tell my neighbors were about to put their septic field on my land. That was going to be ugly.

The new owner of the same house was putting up a fence on the property line without even know where the line was located. I had a chat, showed him the plot and handed him a compass suggesting he shoot the line and see that his fence was on my land. We were near a corner so it was easy.....

Thankfully he moved the fence posts before they put up the expensive fence wire. The fence is six feet tall. He would have been must unhappy when I removed the fence with the tractor.

The money I paid the surveyors was worth every danged penny I paid them. Kept me out of two lawsuits.

How much time and money are you going to spend putting up a fence?

How much money will it cost to pay a surveyor to put in some pins so you can know the location of the line?

How much will the lawyer charge per hour?

How much money is it worth to NOT have to move the fence?

Later,
Dan

 

[TomOfTarsus]

I'm kinda lucky in that I have high resolution orthorectified aerial photos (from the USGS national map), the resolution being 10 cm/pixel. I also had a surveyor precisely locate two corners of my house, as I was putting on an addition and needed to be certain that I wasn't going over the building lines in either direction. I also have access to a CAD program that even works in surveyor's units.

Combining these resources with my surveys, I was able to get an idea of my boundaries that are good enough for now (I.e match anecdotal decriptions), but I wouldn't build fences off of them.

Surveyors have access to GPS units that can get sub-centimeter accuracy, consumer units aren't anywhere near that close, maybe 20 - 30 ft. at best - it's what keeps geocaching fun, rathe than having you walk right up to the cache. But even with the high accuracy GPS, you have to be able to at least project a point from where you are currently located.

With a compass alone, as someone else mentioned, you have to know your local magnetic deviation. I would assume that all surveyors work in true, not magnetic, north, as magnetic changes over time. You really have to watch that.

So I'd say get the surveyor, and just minimize the no. of markers you'll need by thinking ahead as to how you can get from marker to marker with stretched strings or lasers. Everybody knows money is tight, he'll probably work with you on that.

Good luck,

Tom

 

[beenthere]

Beenthere, is there any way you could describe your method a little more? I am having a hard time visualizing what you have described.

Thanks,
Joseph

"Dodge man" described it fairly well (close anyway ). Raising the taught stretched wire at the highest point of the hill so it doesn't touch the ground will allow the wire to want to be straight. I'd expect a few feet of suspension from the top of the tripod (or bipod) would be adequate. A separate plumb line hanging from the tripod as suggested by Dodge man would help knowing when the tripod is moved to the point the taught wire is in a straight line between the two end points.

More than one tripod lifting the taught wire might be necessary to keep the wire off the ground.

 

[Steve C]

Hello all,
I was wondering if someone might be able to help me with a problem I have. I need to build quite a bit of fence on a new property and only the corners are marked with survey rods.

I contacted the surveyor and, for him to come out and stake it every 100 yards or so, will be costly.

I think I can get the straight, flat parts marked out myself. I am just trying to figure out how to get it placed correctly over a wooded hill.

I have thought about putting flares out at night at the bottoms of the hill and use a 1/2" degree accuracy sighting compass and rifle scope. That way, I can go to the crest of the hill and align myself with the compass until I am dead center. Once I am dead center, the compass should read the correct bearing that is listed on the survey, when the light is in the crosshairs of the scope. This is all assuming there wont be too much brush in the way etc. to see the flares.

Does anybody know of any tricks for this? I am not sure if my idea will work or not. I really don't care if I am off a couple of feet in either direction, but would like to get it somewhat accurate.

Thanks,
Joseph

Wait for a evening when there is a little mist in the air. get 2 lasers and 2 tripods. set one tripod over each corner point. Designate the lower corner point as a beacon, and point the laser straight up in the air. Take special care that the beacon laser is perfectly plumb in the plane that is perpendicular to you direction of travel, and it will eliminate any possible deviation from a straight line. Place the second laser and tripod over the other corner marker and shoot it horizontal to intersect the beacon beam. Take a long straight stick with reflective tape on it and a level. Walk about 50 feet towards the beacon beam, hold it up to where it is hit by the horizontal laser beam, plumb it and mark the location. Repeat this process untill you can no longer reach the beam due to elevation or weakness of the laser. Move the horizontal corner laser to the last marked location, and repeat the process. You can just walk towards the other corner 50-100 feet and mark that location, move the corner lazer and the horizontal lazer to that new location and repeat the process, marching up and down hill in a lazer straight line.

 

[beenthere]

That is an interesting approach.
Do you have the name/type of laser in mind?

 

[Steve C]

That is an interesting approach.
Do you have the name/type of laser in mind?

No I do not. I have a couple of $20 lazer levels that I have used to align the blade in my table saw to get it parrallel to the fence. I clamp it to the blade and shoot it to a spot on the wall 40 foot away, mark the location, and move it to the fence and shoot another spot on the wall and mark it. I then measure the distance between the 2 marks and compare it to the distance from the blade to the fence. This allows me to adjust the machine for perfect cuts even when using thin kerf blades. The blade is perfectly parrallel to the fence. I have used the cheap ones outside but they don't have to power to go more than a hundred feet or so. A person would have to find something with a little more hp for my method to work. I have not had a need for it so I don't have any but I am sure that they are out there somewhere if you look around.

 

[jinman]

I have one property line that goes through gullys, over a hill, and through some woods. Both corners are marked with stakes. I placed white markers on each stake and had a buddy fly me over. I was planning on taking photos of my whole place, but during the flight we made a pass around the property and I got one great photo showing both corners. After having the photo, I put a straight line between the two points and looked at trees and identifying features. My neighbor had somebody walk the line and lay it out with a GPS. We were both within a foot of each other. We weren't building a fence, so this was all just for fun, but we were surprised to be so close.

I'm wondering if Google Earth might have enough resolution in your area to do something similar. I don't think I'd build a fence by it, but it would be fun just for comparison's sake.

In the overall scheme of things, when you compare the cost of a good fence and the labor you'll do building it, a surveyor's fee is "chicken feed." I'd hire the surveyor and count his fee as money well spent.

 

[Josephm]

SteveC, thanks for the laser idea. That is really a unique idea that sounds pretty good!

 

[Josephm]

Beenthere, I think I understand your tripod idea. If you clear the top of the hill so that the line is suspended from the ground, a very taught wire will want to pull itself straight.

With that said, if you have the tripod in the incorrect location in the center of the run, the horizontal wire you stretch will want to pull your vertical wire to one side or the other. When you hit dead center, the vertical will be exactly plumb. I have drawn a picture. Please let me know if this is what you mean:

Thanks,
Joseph

 

[Steve C]

SteveC, thanks for the laser idea. That is really a unique idea that sounds pretty good!

I used to be a mechanical designer before I became old and and umemployed.

I found over the years that not knowing how things are supposed to be done is sometimes an advantage when it comes to solving problems. It allows me to use my imagination to explore other ways of doing things that are normaly done some other way because I have no preconcieved ideas of the "right way" to do things.

As a result I have invented several mechanical devices that have been adopted as "M.E.T." (most effective technology) for use in chemical processing plants world wide.

Using the lasers to set the arbor of my table saw perpendicular to the fence is by far the most accurate method I have ever used. When I figured out how to do it the results were amazing. My cheap old cast iron Craftsman saw now cuts great, the blade doesn't rub at all on either side of the cut even when using thin kerf Frued blades.

 

[Pilot]

The way we learned in Forest Surveying class in the early 70's was to use a transit.

First, don't rely on the azimuth on the old survey. Things change and if you look at aerial navigation charts, they show the latest compass deviation and it changes frequently. So the azimuth is only a starting point.

Set up the transit (rent one) on a corner and shoot the azimuth. Use a plumb bob to center the transit exactly over the corner. Set a pin (best to use a stake with a nail in it, the nail being exactly under the plumb bob) out 100 ft.--measure carefully. Move the transit to the pin, then sight back to your corner. You will need a partner with a plumb bob and sight on the string holding the plumb bob. The neat thing about a transit is that it rotates vertically; i.e., it flips up and over to now shoot forward. There is no error from turning. So flip it forward, go out another 100 ft. and set another pin, sight back to your last pin, etc.

What you are doing is projecting a straight line. It doesn't matter if you hit your next corner, you just need to lay out a straight line from one corner to somewhere near the second corner.

When you get out the distance shown on your plat map--say, 2640 ft--you should be near your next corner. Measure the error which should be 90 degrees from your ending point. Then you prorate that error over your line. So if your line is 1000 ft. long and you are off 10 feet, you adjust 1 foot for every 100 ft. along the line from your starting point. If all your measurements are done carefully and correctly, your line should be right on.

You are going thru the woods, you say? What if you have a tree right on your line? You will need to offset. Go 2 pins back, say to the pin at the 300 ft. mark. Measure an arbitrary distance, say exactly 5 feet exactly 90 degrees off to the side of your line. Do the same at the 400 ft. pin, set up the transit at that one, sight back to the 300 footer, flip the scope up and over and sight forward.

Offsets introduce error and you want to avoid them if possible. It is probably better if you have a known obstacle to offset from your starting point and run a perfectly straight line than to have an offset in the middle.

Trying to lay out a property line with a compass is a waste of time. You won't be accurate enough. 1 degree of error equates to 92 feet at one mile. A compass with 1/2 degree error sounds pretty good, but it will still give you as much as 23 feet of error at half a mile and that doesn't even count operator error, errors with declination, or local attraction.

 

[beenthere]

Beenthere, I think I understand your tripod idea. If you clear the top of the hill so that the line is suspended from the ground, a very taught wire will want to pull itself straight.

With that said, if you have the tripod in the incorrect location in the center of the run, the horizontal wire you stretch will want to pull your vertical wire to one side or the other. When you hit dead center, the vertical will be exactly plumb. I have drawn a picture. Please let me know if this is what you mean:

Thanks,
Joseph

Great drawing. Just the way I envisioned it. And a plumb line hanging separate from the top of the tripod should help verify being on-line. Setting up on the top of the hill at minimum, and other locations if the wire wants to drop to the ground, should do the trick. Maybe just a two-leg support would work, as long as it doesn't fall over (and it shouldn't).
I'd think that would get you pretty close to being straight.

Now, you won't hurt my feelings if you try something else suggested.

 

[Steve C]

The way we learned in Forest Surveying class in the early 70's was to use a transit.

First, don't rely on the azimuth on the old survey. Things change and if you look at aerial navigation charts, they show the latest compass deviation and it changes frequently. So the azimuth is only a starting point.

Set up the transit (rent one) on a corner and shoot the azimuth. Use a plumb bob to center the transit exactly over the corner. Set a pin (best to use a stake with a nail in it, the nail being exactly under the plumb bob) out 100 ft.--measure carefully. Move the transit to the pin, then sight back to your corner. You will need a partner with a plumb bob and sight on the string holding the plumb bob. The neat thing about a transit is that it rotates vertically; i.e., it flips up and over to now shoot forward. There is no error from turning. So flip it forward, go out another 100 ft. and set another pin, sight back to your last pin, etc.

What you are doing is projecting a straight line. It doesn't matter if you hit your next corner, you just need to lay out a straight line from one corner to somewhere near the second corner.

When you get out the distance shown on your plat map--say, 2640 ft--you should be near your next corner. Measure the error which should be 90 degrees from your ending point. Then you prorate that error over your line. So if your line is 1000 ft. long and you are off 10 feet, you adjust 1 foot for every 100 ft. along the line from your starting point. If all your measurements are done carefully and correctly, your line should be right on.

You are going thru the woods, you say? What if you have a tree right on your line? You will need to offset. Go 2 pins back, say to the pin at the 300 ft. mark. Measure an arbitrary distance, say exactly 5 feet exactly 90 degrees off to the side of your line. Do the same at the 400 ft. pin, set up the transit at that one, sight back to the 300 footer, flip the scope up and over and sight forward.

Offsets introduce error and you want to avoid them if possible. It is probably better if you have a known obstacle to offset from your starting point and run a perfectly straight line than to have an offset in the middle.

Trying to lay out a property line with a compass is a waste of time. You won't be accurate enough. 1 degree of error equates to 92 feet at one mile. A compass with 1/2 degree error sounds pretty good, but it will still give you as much as 23 feet of error at half a mile and that doesn't even count operator error, errors with declination, or local attraction.

Excelent description on how to do it! Thank you. Now I get to shop for a transit...I have always wanted one!

 

[beenthere]

Pilot
Your suggestion is one I also learned in Forestry. And it is the best if familiar with a transit and can get hands on one.
Your method will likely be the one the surveyors use. They may go out as far as they can see to place a marker, and measure to that point. Then leapfrog to the next point further out. When they can tie into the end point, they will likely turn that angle and with the distances, figure out what the offsets need to be at each intermediate marker.
Prolly the best way, if a transit can be used.

 

[Josephm]

Ok, I have been poking around on the internet. I think I figured out what Pilot is saying.

From my last reference stake already there from the survey, I have 2 I can see back to the road. So I have something like this:

River bank and hill--existing stake 3--existing stake 2---existing stake 1--road

So, I would setup at stake 3 that is already there. Then, shoot backwards to stake 2. With that angle setting, I would flip the transit 180 degrees and then shoot forward toward the river bank/hill - as far as I could see then set a stake there. Then move to that new stake and shoot backwards towards 3, flip, and repeat.

So, a couple of key points that I have heard are:

1.) The transit must be level and plumb bob'd on the reference stake.
2.) A helper must hold a plumb bob infront of you to mark the next point accurately.

Are there any other key tips for this?

Thanks again to everyone for their help!

Joseph

 

[Josephm]

One question I have about Pilot's method. Does the survey plat footage show straight line footage? Or, does that footage account for going up and down hills (ground contour)?

Thanks,
Joseph