I'm curious. How does everyone go about physically setting property corners? I mean do you go out with RTK and work your way to the corner position, and drive a rod and keep measuring to the rod and beating it over until you are correct within a hundredth (or four)? Do you set a (or some) temporary point(s) and measure that in and set up a gun and actually tape it in from the temporary mark? Two marks and double-tape it in? If you don't set temporary marks, and just set it from RTK, do you come back and measure it in on a different day and try to beat it over to mean the difference, or do you just use your second measurement as a check?
Excuse me for asking. I see a lot of talk about accuracy, etc. but I consider it difficult setting a mark at a measurement as opposed to measuring to an existing mark.
(I know it depends.... but how do you set it from GPS and how do you do it from a total station as a general rule?)
Which ever way is most obtuse and difficult must be the right way, right??? Wait that will be what someone else says...
I do it the way you said first. Find the position, drive the rod, check the cap.
Then, on my way back, I will shoot some of them again an hour later for a feel good...
Then, there are always corners that aren't appropriate for RTK, so I will shoot some of the others as a feel good/QC with the total station while I have it set up.
(In a plat for instance.)
With TS I set, turn to the back sight and zero, turn angle again, shoot.
With RTK if its my own stuff I shoot and walk a good distance away, set a nail, shoot second nail, inverse. I then Do the same procedure again at a later time, usually at least a few hours.
Checking the same point at a later time with GPS is useless. Your numbers might repeat within .01' but might be out 10' in reality. Until you remove the source of the multipath you're wasting your time.
[sarcasm]We usually just toss 'em out the window of the truck when we're driving by. Where they land is where the corner is.[/sarcasm]
😀
> Checking the same point at a later time with GPS is useless. Your numbers might repeat within .01' but might be out 10' in reality. Until you remove the source of the multipath you're wasting your time.
This is not the case. I am not sure where you got this information, but this statement is in error. The purpose of a different shot at a different time is to have a different geometry with different paths (including multi-path) for the satellite signals.
For actual factual information on this and many other RTK topics, please click here.
> With TS I set, turn to the back sight and zero, turn angle again, shoot.
>
> With RTK if its my own stuff I shoot and walk a good distance away, set a nail, shoot second nail, inverse. I then Do the same procedure again at a later time, usually at least a few hours.
>
> Checking the same point at a later time with GPS is useless. Your numbers might repeat within .01' but might be out 10' in reality. Until you remove the source of the multipath you're wasting your time.
I suppose it could happen, but I've never had the same wrong RTK reading twice. Checking the same point twice is not useless.
Like many are saying, know the right tool for the right job.
> Like many are saying, know the right tool for the right job.
So what does that mean? Do you know the precision of your rtk work like Kent McM is toting below? Have you gone through a complete check and can say that you have set them monument to the specs called for for ALTA survey?
We don’t use any gps/rtk/etc. at all. Just a 2 man crews with a TS to stake all houses and property corners. I don’t and won’t ever worry about 0.04’. It’s always fun to see all the GPS salesmen telling me how much I could improve productivity with their new miraculous state of the art equipment. Regardless of all the bells and whistles that GPS has we can perform more efficiently without it. Much more efficiently!
Y’all have a great weekend! B-)
> > Like many are saying, know the right tool for the right job.
>
> So what does that mean? Do you know the precision of your rtk work like Kent McM is toting below? Have you gone through a complete check and can say that you have set them monument to the specs called for for ALTA survey?
Personally, I do not set every property corner to ALTA specs (on non-ALTA surveys). I don't know many surveyors that do, though I'm sure there are members on this board who will differ.
Of the boundaries we perform, most are large rural non ALTA's. Our rule of thumb is to set the pin cap w/in 0.02'...in reality I'm comfortable they are 0.04' or so.
Basically what it means is in the woods we use the Trimble S6 to set pins, in the fields we use RTK. We hammer the pin in the ground, and then tweak it until the calc'd point is 0.02' or better.
these days, it's important to have as many tools in your toolbox as possible.
excluding GPS as an option doesn't make sense to me. Like many have said, the right tool for the right job.
I recommend wearing steel toed boots for this task.
(also useful for those existing monuments that are a tenth out)
😉
I knew you guys would have it all figured out. If you don't want to hear my "ramblings" you might stop here.:stakeout:
I grew up surveying in a culture of running a traverse and getting precisions that almost always exceeded 1/100,000 closure. The firm I worked for would set corners from a traverse point generally by turning the calculated angle, getting a rough distance and going around 2' past the calculated position and setting a stake on line. We would poke a hole in the stake and then turn the angle again from the backsite in reverse and mark another hole and the rodman would split the to marks and set a sight-tack. We would measure to the sight tack, and figure how far to come back to the instrument. We would use a hand-tape and set the monument while the instrumentman gave line. We would then either traverse through the pin we set, or at minimum, shoot it from another setup.
This was pretty tedious but provided a fair amount of precision. The firm I worked for had the 'we measure better than you do' syndrom and virtually never accepted other pins (of course you had to come from somewhere, and that somewhere was usually the point of beginning, or the original subdivision control).
This setting of pincushions always bothered me even as a new rodman. by the time I was licensed I had come to the conclusion that you don't keep setting pins within a foot of others. And since then I have become an even greater advocate of JB Stahl's and Jeff Lucas' preachings. I am more prone to use monuments I find, even if I don't know where they came from unless I have enough evidence to dispute them (more than an angle and a distance).
So, having adopted that philsophy, I wonder why I care about setting my monuments more precisely than within a couple of tenths?
What about original corners? Do you go through a higher level of care when your monuments are the first original monuments of a boundary?
I still hold the position that all of my work should have a certain acceptable order of precision, but I see it all around me where people use RTK or spray in corners and set them straight from one angle of the gun. Yes, often times they double check their locations to ascertain there wasn't a "bust". If I follow behind those surveyors I will accept their corner monuments as well..... So what's the use of precision anyway? I am uncertain at this time. (Oh yeah, and don't get me started on subdivisions and/or legal descriptions that don't even close. Again why do I worry about the hundredth after I have worked out the descriptions 10' bust.)
Every other surveyor I know never has any of this "doubt" about the right way to do things. I guess I take that stance too a lot of times. But what do I know (maybe I'll as my wife; she usually knows everything).
