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Survey Nails and Benchmarks


RSCONSTRUCTION

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Were they measured for inclusion in the data base?  That's really what matters for logging here.  Generaly, don't bother trying to put them in Waymarking if they weren't in the data base.  A nail is usually a temporary mark unless set in a very solid mounting.  You won't find many nails in the NGS data base and the geocaching list of benchmarks is an old snapshot of the NGS data.

I HAVE seen a few nails in the data base, but they were part of US Geological Survey work that included disks and got added to NGS, but those nails (usually in wood) weren't really permanent enough and probably shouldn't have been included.

 

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RSCONSTRUCTION,

Lots of non-standard marks with PID's out there.   This link will cover most of them.

    https://www.ngs.noaa.gov/web/about_ngs/history/Survey_Mark_Art.pdf   

Early on I had a lot of fun trying to figure out if 1/4 inch threaded bolt was what had been placed on a building front in Belgrade in 1907 during the PLN (Precise Level Net) run between Butte and Huntley, Montana.  See Note 4, Page 162 (168 of 334 on line ) in Special Publication #18.

Have fun filling your quiver.

kayakbird

 

 

 

 

Edited by kayakbird
To correct date of PLN run.
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On 9/21/2017 at 9:24 AM, Bill93 said:

Were they measured for inclusion in the data base?  That's really what matters for logging here.  Generaly, don't bother trying to put them in Waymarking if they weren't in the data base.  A nail is usually a temporary mark unless set in a very solid mounting.  You won't find many nails in the NGS data base and the geocaching list of benchmarks is an old snapshot of the NGS data.

I HAVE seen a few nails in the data base, but they were part of US Geological Survey work that included disks and got added to NGS, but those nails (usually in wood) weren't really permanent enough and probably shouldn't have been included.

 

These nails I've seen don't typically have two letters followed by four numbers like other benchmarks, but rather just four numbers. They often do have a trianglulation symbol drawn around them or painted next to them. These nails range from MAG nails to 60D's and others. 

Most of them also have a plastic washer labeled "Survey Marker - Do Not Remove". If not, they have Survey ribbons under them that range in color from orange to blue or pink, and sometimes multiple colors. 

Edited by RSCONSTRUCTION
To add more details about the nails
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15 hours ago, kayakbird said:

Looks like a temporary point - maybe placed by your DOT (state or county roads).  What is your location?  I have most of the western states in GSAK based Excel files and could maybe suggest some interesting PIDs in your area. 

kayakbird

I'm am in Loudoun County VA. Most of these nails they seem to use to set up total stations (survey tool) on them so they can see property markers, or lines of sight. I talked to the surveyor who was here a month ago surveying property lines for the developer's  lien. I saw him replace missing nails with new ones. 

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It's almost certain these nails do not have high-accuracy geodetic coordinates, and won't be in the NGS data base so you can log them.

They are either cadastral (property corners or reference marks to find those) or for construction (e.g. upcoming road work).  A curb is not stable enough over decades, and a nail in a crack less so, but are useful in the shorter term.

The painted numbers you see near those nails are the point identification the surveyor uses on this project, and won't be part of any larger scheme.  It is rare to find the NGS PID (like AA1234) marked on an NGS point. Their procedures do not call for marking a PID, just a DESIGNATION.  Sometimes a user will paint the PID on the concrete or a stake to help find it during their work in the area.

Edited by Bill93
Add info
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Thanks Bill93 for that info. 

I went to a neighborhood near my area that is fairly new (still under construction) and found a good example of a nail in the curb with the markings I've been talking about

I believe the mark that is here is the MAG nails PID. 

But why do they have the triangulation marking? That still leads me to believe that they have an NGS or benchmark related status somehow? 

IMG_7112.JPG

Edited by RSCONSTRUCTION
To add details
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Anybody can paint a triangle around a point for whatever meaning they want to give it for their own purposes.

I don't see a 2-letter, 4-number PID there, which is the format used by NGS.

I'd suggest that you not pursue the route of finding some mark and then trying to figure out what it is.  

Look in the geocaching data base for some marks that have been found by others and locate them yourself to get familiar with what is typically in that data base and the environments where the were typically set.

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A few, quick, Excel data sorts on Montana's 15911 PIDs comes up with 211 that were placed by the GLO (Government Land Office) and just over half of those are cadastral points in the rectangular survey used out west.  SP0396 was of interest to me because of the three shallow pits which had not been noted in the data sheet prior to my recovery.

Others might have 100 plus year old bearing trees for RM's, but chisel marks or Monel rivets on railroad structures may be easier to find in your area.

kayakbird

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I have seen a number of triangle markings on what was obviously a local survey. Those points might be county-placed marks (especially the one marked T103), or just something local surveyors placed while doing work. They would have marked them with a triangle because the indicate a horizontal point, just like a tri-station. 

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Nails are typically work points.   MAG nail is a brand of magnetic (for surveyors use) masonry nail, another is PK (Parker-Kalon).  Actually the PK nails never had a center point but they found out surveyors used them so much they started to make with a defined center point.  At the DOT we used these for all construction lay out, centerline alignment points, bench marks, traverse points etc for project work.  We had brass tags about the size of quarter we often put the blank side up. I seen professional surveyors use similar with the license number, name etc to mark one of their control points or witness.   In short, mostly used as work point, cost effective.  I seen them used by non-surveyors to mark important locations, police accident reconstruction for instance or builders.  

f8a6a15f-bb46-4fdc-a350-e80be7e0e3e2_zps

PS-When we used flagging with the nail we called it "gift wrapping".

Edited by Z15
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