laser grading

[rrayw747]

We are cutting a ditch at a grade of 0.1% using a GRADALL and a rotating laser. Where is the absolute best position for the tripod mounted laser to insure optimum accuracy?
How do you deal with curves in the ditch? Any other basic information in this area would be helpful. thanks, rrw

 

[TDAA]

You will want it relativly close to your work. The further away, the more any error will be magnified.

If you are using a laser that you dial in a percent grade, I do not believe that will work for the curve. You could set it up flat, and figure the appropriate depth from the laser at specific intervals.

 

[Hoagie]

Ask your engineer for a plate detailing flowline grades at the beginning, midpoint, and end of curves. You will have to apply some basic leveling methods to calc the 'foresights.'

I'd keep the instrument far from your work area so it isn't influenced by machinery. If it's a laser-beacon, there won't be any significant error regardless if its close or further to the work, save the instrument and human-types.

I hope this helps.

H.

 

[rrayw747]

Thanks guys for your input...rrw

 

[LCruiser]

The only place to put the laser so as to be able to use it through a curve is a the center of the arc - which could be a fair distance away... You might want to find out what the tolerance is on the grade, then move it every so often. You could move it every day, or twice a day (at lunch) or something like that. It would depend on what the size of the ditch and its use will be.