Do you guys rock your rods? If not, why not?
Back in the Midwest we had a lot of relief. Most of our work was done with automatic levels and mound city rods. Rocking the rod gave us good results.
Here in the valley things are pretty flat. It's unusual to read more than 8 feet so we use Philly or bar code digital rods. Those lend themselves to using a rod bubble holding plumb and steady.
It's best to have both handy. A Surveyor can never have too many tools...
Webbed feet, post: 322646, member: 10038 wrote: Do you guys rock your rods? If not, why not?
No- Digital level- it's 2015
It's not a bad habit to have the rodman give it a 'rock'. Although I've found it difficult to find a rodman that can rock it correctly. It's almost like you need to run the gun before you actually know how to rock the rod properly. We keep a bubble with the level rods nowadays. Seems to work.
Rankin_File, post: 322651, member: 101 wrote: Digital level- it's 2015
Saw one of those once reading a rod that was 30 degrees out of plumb...
Rankin_File, post: 322651, member: 101 wrote: No- Digital level- it's 2015
At least you didn't say RTK I guess...
I have heard that trimble digital levels have a routine for reading a rocked rod but did not believe it at the time.
I do not rock a rod on a flat surface, when using a digital level, when using a pocket tape, or when taking a shot on one section.
It's been all TS or digital for me for years.
[USER=10038]@Webbed feet[/USER] - that's why you don't rock them- you set them up plumb/ communicate with the instrument man and let him take the shot-
btw- back when we ran optical level instruments - we did wave the rod.
Rankin_File, post: 322663, member: 101 wrote: [USER=10038]@Webbed feet[/USER] - that's why you don't rock them- you set them up plumb/ communicate with the instrument man and let him take the shot-
btw- back when we ran optical level instruments - we did wave the rod.[/QUOTE
Fine if you are on flat ground, if your bubble is at 4 feet +- how do you know you're plumb at 20 feet?
Webbed feet, post: 322664, member: 10038 wrote:
if I was concerned enough about my level loop to be waving the rod, you can bet I wouldn't be using a 25 ft rod in the first place... our digital rods are 3 meter folding rods...
No dirty comments yet about wives/girlfiends/etc rocking our rods?
I do, but then I don't get the digital, I just grab the old equipment when I head out, leave the new stuff to the young guys, I feel safer that way.
And I still will have the rod waved at me. And I will still peg the level. And I will still read three wires.
[USER=700]@MightyMoe[/USER] - why do you think I grab the rod when it's time to run levels- :-D- besides most of the problems in a level loop come from WHERE THE SHOT WAS TAKEN
We use a digital level. Our digital level will not read if the level is out of level and the rod is not plumb. Id has an error code for each condition. The only busted loops happen when someone reads a rod optically. For those of you still using optical levels, how often do you have to re run a loop? We routinely get 2nd order closures when we close back on a loop, using fiber glass rods and truning on a screw driver stuck in the ground.
I have never used a digital level, but why would you need to rock a digital level rod? I understand rocking a optical level rod to help see which number you are reading. Btw in college we watched an Australia video on how to run a level loop, they call the rod a staff. We had a few survey ninjas during the field part of the lab. When I get a new guy on my crew I tell him to get the staff, we need to run a level. Most of them are smart enough to figure it out.
Rankin_File, post: 322765, member: 101 wrote: [USER=700]@MightyMoe[/USER] - why do you think I grab the rod when it's time to run levels- :-D- besides most of the problems in a level loop come from WHERE THE SHOT WAS TAKEN
When it's time to get it right, then it's time for me to stay away and let the boys do their thing:-) I'm just around to do fill in.....you know little stuff here and there
Scott Ellis, post: 322778, member: 7154 wrote: why would you need to rock a digital level rod? I understand rocking a optical level rod to help see which number you are reading
Rocking the rod isn't just for reading the digits. If it's tilted the line of sight will intercept a higher mark and give you error. A bubble level on the rod makes it easier to maintain plumb, but waving the rod is the time-honored substitute. The instrument operator takes the lowest mark that the crosshair intercepts.
I can see that the digital level might be designed to detect when the rod is tilted sideways, but is it smart enough to know that the rod is leaning toward or away?
typically, you set your inst up to take several reading, 3-5 and use a mean- if you're waving around- it gives you an error, and yo get to try again...plump it up and hold still- NGS used bi-pods for their runs- so what does that tell you about rocking?
I always rock the rod or ask to have it rocked if I'm reading the level. I figure it can't hurt. It may seem crazy, but I prefer reading the level to a digital. Then again, I seldom run loops anymore, but when I did I was able to get very good closures over 2 miles or more using this method, a cheap-o level and balancing the distances on turns. I always run a peg test in the beginning if it's for control or something with very tight accuracies.
I previously worked for a firm that picked up a project for underground gas storage caverns and the specs required the level loops to close within 0.01 foot. We purchased a Leica digital level and the loops were phenomenal. After I left, it went into disuse. No one liked using it because the optical was faster for most of the work they do. We do not have one in our firm and still use the optical as I feel for construction staking it to be faster. If I am wrong, let me know.
