Laser Grading

[Industrial Toys]

Maybe that is where GPS would be more usefull than a laser. If you have to cut six feet it can tell you that.

Jenkinsph. How do you get the laser up that high? Do you have a regular tripod and then a pole?

 

[jenkinsph]

Maybe that is where GPS would be more usefull than a laser. If you have to cut six feet it can tell you that.

Jenkinsph. How do you get the laser up that high? Do you have a regular tripod and then a pole?

I think the GPS systems are great but I can't make that pay or afford those systems anyway. A good laser set up with two receivers, hydraulics with proportional control and a good laser runs about $12,000 best I can tell. GPS would be $25,000 and beyond.


About the height of the laser, I am planning on 10' to clear the cab of my tractor and a larger tractor later if needed. The mounting for the laser has to be rock solid for long distance use or all is lost. I will likely buy a very good elevating tripod for the short shots and make a larger heavy duty stand for the longer field shots. Wind can be a real problem in my locale in the early spring when most of the leveling work is taking place. When you consider a 1000' shot it doesn't take much movement to have the laser line jumping up and down and worthless. I am working on a drawing now to design a good stand for the field work.

 

[dodge man]

Yeah, GPS is very expensive to add for machine control. What's nice about GPS is does the vertical and the horizontal at the same time. If you are grading a site all at the same elevation, it doesn't matter but for something like a highway, it works great. GPS is accurate to about and inch in the vertical, which is good enough for dirt work but not paving. Topcon actually makes a system that combines GPS and lazers for use in paving. Needless to say its big bucks.

I'm not sure exactly what it cost to add GPS to something like a dozer or motor grader. There is usually a GPS antenna on both corners of the blade. I'd just guess your talking $50,000 or more by the time you add everything up.

For reference, a survey grade GPS system, which is accurate to about an inch, cost in the neighborhood of about 20 to 30k. It also takes a lot of training and experience to learn how to use it. The companies that are big into machine control usually have someone on staff that understands all this stuff and also knows how to setup the files that are loaded into the controller that the equipment operator follows. A lazer system is much easier to use for someone starting out.

 

[Industrial Toys]

If you have a thousand foot range on the laser, it's a thin beam and you only have let's say a foot or so of receiver looking at that beam, how is that supposed to work?

Still curious about the single and dual slope, understanding neither!

 

[dodge man]

If you have a thousand foot range on the laser, it's a thin beam and you only have let's say a foot or so of receiver looking at that beam, how is that supposed to work?

Still curious about the single and dual slope, understanding neither!

Say your laser is setup at elevation 105. Say you want what your are grading at elevation 100. You would put your receiver at the point on your rod where it picks up the beam and see where you are at. Say the beam is picked up at the 10 foot mark on the rod. It should be at the 5 foot mark to be at grade. This means you need to fill 5 foot of dirt to be at grade.

Say the beam is at the 2' mark. That means the elevation is 103 and you need to cut 3 feet of dirt to be at grade.

Hope that makes sense.

 

[Industrial Toys]

You speak of a ten foot rod. THAT would make sense. But some of the receivers I see are only like a foot long. Maybe not even that. That is an awfully small window to work with.

 

[jenkinsph]

You speak of a ten foot rod. THAT would make sense. But some of the receivers I see are only like a foot long. Maybe not even that. That is an awfully small window to work with.

Most of the receivers that are a foot long only pick up a band of 5 to 9 inches. If you are willing to spend several thousand you can get a wider band and a motorized unit which will scope up and down the rod. When I start out grading I usually cut down the highest spots and pull them to the lowest spots. I can then run a landplane grader blade over the field to smooth everything out. I don't see the need for a laser on the machine to help me determine where to make a 5' cut or fill in a similar hole. 90% of grading work is smoothing out the last 10% of the job. For my work leveling irrigated fields the water levels out and tells the story, everybody knows whether you get it right or not.

About the single slope vs dual slope, you can set the angle of slope you wan't possibly to follow terrain or to an incline. With a dual slope laser you can set up two slopes at the same time, for instance you might need to set up for a 10 degree slope running north to south and only 2 degree slope east to west. The laser is not set up level all the time like you might do for grading a concrete slab.

 

[Complete Turf Care]

You speak of a ten foot rod. THAT would make sense. But some of the receivers I see are only like a foot long. Maybe not even that. That is an awfully small window to work with.

You have to move the receiver up or down on the rod to get within the working range of the laser beam.

I have a dual slope laser transmitter. I use it to grade football fields. Here is an example of how 'dual' slope works.

If I set up my transmitter behind the goal post in the north endzone, and I want to grade my field to have a peak at the center of the field (in a straight line between goal posts), and I want it to slope towards the sideline (east and west). And, I also want it to slope towards the south. A 'dual' slope transmitter allows me to set my laser in both east and south directions, or west and south. A 'single' slope transmitter would only allow me to set my laser in one direction. South, or east, or west. For my needs, a 'dual' slope was my only option.

They also make a 'cone' transmitter, which is for use in constructing baseball fields, where the transmitter is set up on the pitcher's mound, or home plate, and the field is graded outwards from there.

 

[Complete Turf Care]

And, a remote to adjust the slope is a good option.

And different brand receivers should be compatible with transmitters. In my case I borrowed a 'cone' transmitter to do a baseball field, and it was a different brand than my transmitter, and it worked flawlessly with my receiver.

 

[dodge man]

To use the laser, most people use a level rod, they can be up to 25' long but most of the time a shorter one is used for a laser. The way I've seen them used the receiver is attached to the rod. If the guy doesn't know where the beam is, he just lifts the rod up and down until he finds it. You then have an idea where to put the receiver to get the signal.