Anybody done much DIY surveying ?
My problem is pretty simple. By using hand-held GPS (which is nowhere near accurate enough, by itself, to locate survey irons), and curve fitting my GPS readings to the known bearings and distances of my lot lines, I have managed to predict the GPS coordinates of the ones I could not find, and thereby locate them (the hand-held GPS could get me within a 20ft circle or so).
So I now have found all my property irons (or "monuments"), and I now need to try to flag one of the lot lines. (This is to help the loggers who have the timber easement on the neighboring property to not trespass on my property again - but that's a whole 'nother story). The line is about 900ft long and heavily wooded, a lot of it pretty scrubby stuff that is nasty to clear through. So I can't just eyeball the line between the two irons and flag trees, because I can't come anywhere close to seeing one iron while standing at the other. So I need to transit the line (I guess that's the right verb). I tried it with a hand-held hikers' compass (with flip-up sighting mirror) and missed the other iron by about 20ft. That's about 1-degree accuracy, which I think is pretty good for hand-held, but the 20ft error at the other end is certainly not good enough for flagging the line. And it's not even good enough for clearing the line - I don't want to have to clear a 20ft-wide swath !
So I have built a home-made surveyors transit, roughly as described here:
http://chestofbooks.com/crafts/popu...s-to-Do/How-To-Make-A-Surveyor-s-Transit.html
I haven't tried it yet, so more later ...
My problem is pretty simple. By using hand-held GPS (which is nowhere near accurate enough, by itself, to locate survey irons), and curve fitting my GPS readings to the known bearings and distances of my lot lines, I have managed to predict the GPS coordinates of the ones I could not find, and thereby locate them (the hand-held GPS could get me within a 20ft circle or so).
So I now have found all my property irons (or "monuments"), and I now need to try to flag one of the lot lines. (This is to help the loggers who have the timber easement on the neighboring property to not trespass on my property again - but that's a whole 'nother story). The line is about 900ft long and heavily wooded, a lot of it pretty scrubby stuff that is nasty to clear through. So I can't just eyeball the line between the two irons and flag trees, because I can't come anywhere close to seeing one iron while standing at the other. So I need to transit the line (I guess that's the right verb). I tried it with a hand-held hikers' compass (with flip-up sighting mirror) and missed the other iron by about 20ft. That's about 1-degree accuracy, which I think is pretty good for hand-held, but the 20ft error at the other end is certainly not good enough for flagging the line. And it's not even good enough for clearing the line - I don't want to have to clear a 20ft-wide swath !
So I have built a home-made surveyors transit, roughly as described here:
http://chestofbooks.com/crafts/popu...s-to-Do/How-To-Make-A-Surveyor-s-Transit.html
I haven't tried it yet, so more later ...