establishing crown and grading

[alexis.marcil]

Hi,

What is the recognized technique to establish a crown in a gravel driveway? Can it be done with the front bucket even if it can't be angled?

also, how can you grade with a tlb while keeping the crown in the road?

thanks

 

[Dickjr.]

It may be possible if you have enough witdth form the center of the road for the edge of the bucket to run from the center both side. I always thought anything could be done with a backhoe until I bought my Komatsu D39. A little patience and anything can be done.

 

[JS580SL]

I agree with Dickjr. Patience is key. It can be tricky using a backhoe but with time and experiance its very do able. Swinging the boom to one side can help a little bit sometimes. Shifts the weight enough to help one side of the bucket cut a little more. As far as spreading gravel level, think of it some what like a butter knife.

The hardest part is going to be getting started. Like Dickjr said as well you really need enough room to make a crown on a driveway. Do you have a grading/cleanup bucket?

 

[RonG]

When you have done a fair amount of grading with a backhoe or for that matter any rubber tired machine you soon...............or eventually at least learn how important tire pressure is to getting the job done properly.You can use that to your advantage by lowering the pressure on one side and you will find that you can grade in both directions,one side going and the other side coming back and make it look like you know what you are doing.
I generally prefer a rubber tired machine when grading driveways from the garage to the street to prepare for paving because you can back right out on to the pavement whereas using a dozer inhibits your range of travel so the loader bucket allows you to grade and move excess material from driveway to driveway in the "process".That is when you realize how important tire pressure can be,at least from one side to the other.They need to be equal to keep the machine level.Ron G

 

[AussieChris]

Just put a large bucket on the back hoe and fill it with dirt. Then just swing it to one side (doesn’t have to be way out beyond the width of the machine). The rear tyre should bag out enough on that side to tilt the front bucket.

 

[RonG]

Just put a large bucket on the back hoe and fill it with dirt. Then just swing it to one side (doesn’t have to be way out beyond the width of the machine). The rear tyre should bag out enough on that side to tilt the front bucket.

The problem with that is that it takes weight off of the drive wheel on the opposite side and it spins easily which is just what you don't want.No need to be digging holes to fill in again and it robs you of pushing power.Ron G

 

[AussieChris]

Yes, that’s a good point Ron and I hadn’t considered that problem. I guess it’s not so bad on a 4WD machine (and I have a diff lock if needed) but I was thinking more in terms of pushing loose material rather than cutting hard ground.

Chris
Brisbane Australia.

 

[handtpipeline]

I prefer to use the backhoe boom as a counterweight to "tilt" the machine some. You can lower the tire pressure on one side, but unless you have an air compressor handy, it's a pain to air back up. In harder material, I have kind of "pre-ripped" the material where I want to cut deeper, by using the rear bucket teeth as a sort of ripper, driving forward with the teeth just barely digging in. Then when you use your loader bucket, it'll dig in easier on the side you ripped, helping tilt the machine some. Of course, I'd rather use a dozer or the grader, but sometimes it's easier just to use what you have on the jobsite.

 

[oceanobob]

I have found what was mentioned above to be the point - you have to get started. Assuming the ground is flat and the area is narrow, I have learned to take the bucket and as I enter the stock pile, cause the bucket to go sideways by steering sharply so the bucket only gets material on the one side or the other. Then dump/spread this material in the area that is low, or in this case where it is to be higher. Gently backdrag. Soon the material will be angled and from that point on, remember to keep the rear axle in that zone and the profile can be continued using the full buckets and back dragging. Make adjustments as above, or turn the tractor around and use the hoe to trim (see below).
This is the other way that I do this: I have an extra 2' bucket with a four foot wide straight blade about one foot tall. Some folks have 'em wider, this size is pretty good. Get the compacted subgrade centerline fairly correct in elevation and not so important on the shoulders - just high or a little high is good for these areas. Turn around and set the outriggers just to touch to reduce bouncing when you unlatch the boom (I have Case), then place bucket on ground to just one side of center and lift machine slightly and then press outrigger back to ground. This will angle the machine and blade and not dig scrape marks with the ourigger pads, or cause the tractor to move sideways. Cut the excess with the straight blade, then pull the spoils to you as you do so. Set bucket on ground near center and lift machine, bias the outrigger the other way and repeat above on the other side. Then back to center, hold outriggers up, raise em slightly, lower machine down, complete final raising. Bring boom up, turn your seat, move ahead about 6 or 8 feet.
Turn your seat, set up, move the majority of the spoils pile to you and repeat the above. When pile is pretty big turn around and pick up with 4:1.
Since the center grade is set as per above, you should not dig on the center - only the sides of the crown.
When I first got the backhoe I wanted a dozer w PAT blade but now I can do these things with the 'hoe since it is usually the machine that is on the job already it saves me from hauling another machine.
Sometimes when backdragging, you can swing the bucket to one side but it doesn't have the same effect as an articulated loader. And you can back into something too!

 

[Conn]

learn how important tire pressure is to getting the job done properly.You can use that to your advantage by lowering the pressure on one side and you will find that you can grade in both directions, Ron G

What pressures do you typically use? For eg. 15 psi to 35 psi. Do you adjust all 4 tires, or just the rears?

 

[RonG]

I never measured the result of lowering the tire pressure.Just let enough out to accomplish your task.I must say that I never really did that intentionally but have run many machines with a low tire and know what it can do to your attempts to grade while in that configuration.My objective when answering this post originally was to give some direction to someone with possibly limited experience to help get the job done.
It would be an option if I had long stretches of road to maintain but I would likely either do my grading by getting my machine in position to establish my grade which involves some of the techniques that oceanbob has posted or more than likely get the correct machine for the job.
I would think that lowering the pressure 30% or so could be done safely with a plan in mind to air it back up as soon as possible after you complete your task.
Almost any operator here has run rubber tired machines that have a chronic leaking tire on them,sometimes they go for months and more before the leak gets repaired and they all know what it does to any attempts to carry a grade.
Running those machines is good practice because you learn the principles of grading by virtue of the machine forcing you to get it in position to accomplish your goals.
Ron G

 

[Revicm]

This is something I have been wondering about for a year now. Thanks for all the enlightening posts. The only driveway I have to do is my own on the farm I bought a year ago, but its the most important. Two bellydump loads of A and I am still working on it. Any other grading I do (when at work) is on shoulders and its just to fill old post holes.