> Was this one of those control points for a big Highway job? Someone probably sat up their GPS on it and collected data for an OPUS session; when they found out the coords' didn't match, they adjusted to fit.
>
> Am I close?
>
> :snarky:
> B-)
No Radar. It is for a large preliminary route survey and generally, if asked, we will share benchmarks and control for checks, convenience and what not, but this particular control point is for the most part private information.
Beer,
Were your coordinates inked in just beyond the range of the photo? Can't think of any reason to do that except for conventional instrument visibility, but moving that much isn't going to improve line of sight anyway.
If that was not done in jest, it must have been done by the guy that I worked with a while back that used to make chainmen move 1X2's to fit design coordinates and then tack hubs set for clearing limits. No, I am not kidding.
By the way we use WTF, in these parts. like the Hoffman boys do on Gold Rush.
JA, PLS SoCal
> Beer,
>
> Were your coordinates inked in just beyond the range of the photo? Can't think of any reason to do that except for conventional instrument visibility, but moving that much isn't going to improve line of sight anyway.
>
> If that was not done in jest, it must have been done by the guy that I worked with a while back that used to make chainmen move 1X2's to fit design coordinates and then tack hubs set for clearing limits. No, I am not kidding.
>
> By the way we use WTF, in these parts. like the Hoffman boys do on Gold Rush.
>
> JA, PLS SoCal
That's the thing JA, the coords are only known to our two crews and nobody else. They are not inked or written on lath or have been published in any way. If they were "correcting" the control point, I don't know what they would of been correcting it to because they don't have that information.
Yeah we use that term here also but I'm just following forum rules. Believe me, I had some other choice words when it was discovered....
Tacking clearing limit hubs? Hmmmm.... It sounds like that chief needs one of these manuals to study.
Here's a link to a another pretty good manual for him...
Beer Legs,
What did you use to get such a nice scribe?
A battery operated [msg=227562]cut off grinder[/msg]. It works real slick. 4 seconds and you have a real nice cross cut.
I've inadvertently done that when cutting a control point. I use a diamond-blade saw, and sometimes I'll try to deepen a cut but slip and end up with two crossing cuts.
I wonder if one of your own crews was trying to "clean up" the original and ended up making a hash of it.
The other crew didn't owe up to it, and I believe them.
We recently performed a precise control network with the proper equipment (0.5", 1mm instrument with the tribrachs and strider bubbles etc. calibrated to the instrument by the factory), procedures and documentation. We had the contractor pour 3'x 3' blocks of 3 sack concrete for our placement of the control monuments. Once the monuments were set in the prescribed locations, we recorded redundant measurements from various setups- accounting for most sources of error and then, performed error analysis.
The end result? The contractors surveyor came out and set cup tacks 0.02'-0.03' from our brass brads based on a single angle and distance radial stakeout.
I went out with another guy (years ago) and staked a building. We staked the corner hubs, turn 90's direct and reverse, tweaked, double-checked distances, and when we got it where we thought we wanted it, we measured diagonals and got the building right-on and set offsets. I think most guys go through this kind of rigorous work to set building corners.
The contractor came out the next day and complimented us.... But then the kicker. He said he checked our work and it was exactly right-on. He said that most the time he checks other surveyor's work and has to beat the hubs and tweak them until he gets them right on. I was thinking that this was probably merely the first time that his checks matched the surveyor's layout. All the other times he was probably moving the hubs off of a good layout.
Another job we did the same year, also a building. Staked it out one day, and the boss comes up to us in the nice mountain job and calls us back to check the old job. Seems that the contractors in-house "surveyor" checked our work and thought we were a foot off. We checked and double-checked every measurement and all the diagonals. everything was great. Told the contractor that it all fits like a glove. I'm sure we had to charge him for breaking off another job and coming 30 miles into town to find out we were correct. I am guessing that maybe their inhouse surveyor didn't last to long at that job.
Heh... Well at least he had something to pincushion to...