At the risk of seeming ignorant, I have some questions about Laser Levels. I haven't ever used a Laser Level before, and I would like to know if it is practical for grading construction stakes. However, I am not talking simple layout of a pad where the elevations are the same at each stake; consider grading stakes for a road in a subdivision. I think it would be fantastic if one could setup a laser level, walk to a stake, find grade of an elevation, or adjust for cut/fill using the controller on the level rod. Of course, this would imply that I am looking for a unique elevation at each stake and not the same elevation at each one. Is this wishful thinking on my part?
Absolutely. All it does, at least the one we had at the time (15 years ago), is give you a constant reference plane and you do the rest just like you would do with a regular level. I don't have any idea what the current state of the technology is today. Basically it gives you the ability to do one man grading.
Darrell,
It's easier to just take the prism off the rod, (adjust the rod ht) and place it on top of the stake, then measure down from the top of the stake for your grade.
I have Topcon laser level (RL-H3C), It is the entry grade of the Topcon line. I really like it. I use it all the time for elevation certificates when working by myself.
I regularly close level loops with it 0.02'. I keep it calibrated, and I treat it with care. It has it's place. I have used it in a manner that you describe, however, I would probably use the robot for verticals if I had very many stakes to grade, especially if there was alot of vertical difference.
It is really helpful if you have some grades to check by yourself.
Good luck.
They work pretty well for a reasonably
level area.
I used one to grade the road connecting noble park to Cairo Road as seen on this map - if the google map link works correctly. The stakes had been placed on Friday. Saturday morning, I went out and graded them by myself so that we (the field crew) could head to an out of town project on Monday morning with no delay.
I've also used one on a railroad spur. That project worked very well also.
Either you can set a stable point at the grade stake then slide the laser receiver to the foresight reading or you can preset the calced foresight reading and slide the level rod along the grade stake to mark.
Works very well and they actually can get good data.
Laser Levels
I haven't been around one for years so they might be much improved by now. My recollection is that the contractors' ginny-hoppers would be using one to grade a site and they would push it beyond its horizontal limits of accuracy. They'd come up to us while we're staking the site and tell us there's a problem but it would turn out they were a little bit out of level and trying to use their laser level beyond its intended range. For installing paneling in a room they're swell, but unless they've improved a great deal, I wouldn't want to try and grade a very large site with one.
Laser Levels
Steve: wouldn't moving the laser level to a new point solve the distance limitations?
Laser Levels
Laser level with a lenker rod is quick easy and accurate. I do construction stakeout with my hiperpros then grade with the laser.
Laser Levels
I have personally checked vertical accuracy of my LB-4 in single plane, fine mode to 800' with .02' error. I did not expect it to be that accurate.
Most newer lasers allow for XY gradient inputs assuming you are working on a straight horz vert alignment. They are actually very useful tools.
Laser Levels
AGL makes a Smart Rod that lists for $595 that diplays either the elevation or cut/fill based on a benchmark. You need a good self leveling laser to use with it. They cost between $900-$1500 depending on the range and accuracy.
Laser Levels
:good:
Another way to make your roadway staking easier is to utilize a robotic total station. I use the Trimble 5600 series with the ACU controller.
I enter the roadway information from the plans and am able to give cuts and fills anywhere within the roadway limits. It is very easy to enter vertical/horizontal offsets to stake sub-grade and RP's on the fly. The roadway work goes very quickly and has proven it's reliability over numerous road, landfill, and airport projects.
I also utilize surface models to stake larger parking areas.
The only reason I mention this is that is it much much faster than a laser level and much more flexable.
If you want to establish an elevation, stake out a dummy point with an elevation of 0. Set your rod down, the cut will be your elevation.
I know times are not good for upgrading, but the market is flooded with used robots.
JRL