Dirt Moving Bulldozer blade cutting angle

   / Bulldozer blade cutting angle #1  

timbatrader

Silver Member
Joined
Oct 6, 2012
Messages
248
Location
Pakihi New Zealand
Tractor
YCT306S-S bulldozer Leyland 344 tractor, Mountain Raise MR926S wheel Loader, Hitachi 19U mini Excavator
I am having trouble controlling the depth of cut my blade takes My Yuchai YCT306S-S dozer has a six way blade so I can control every angle except the cutting angle.
On my Bobcat skid steer I can lift the front of the fourway bucket to leave a dozer blade by using the tilt function I can control the cutting angle to get a continuous push. On the dozer without control of the cutting angle the blade keeps digging in requiring me to back off leaving a series of divots rather than a smooth track.
One way to describe it would be to think of trying to chisel out a rebate in timber with the chisel the wrong way around the chisel keeps digging in.
As I am a timber machinist by trade I am thinking in terms of timber machinery. The angle on the dozer blade is the equivalent to a circular saw with a hook angle of 30 degrees, which is very aggressive and will pull the timber in.
First Question am I right in thinking this is an aggressive angle that is giving me problems or is it just poor operator technique and I need some schooling on how to operate
Second Question can I get some feed back as to the cutting edge angle on other machines dozer blade measured in degrees off vertical i.e. a straight up and down blade would be zero degrees
IMG_0835.jpgIMG_0837.jpg
 
   / Bulldozer blade cutting angle #2  
What are you trying to push with it? Dirt, then you need to watch the blade like a hawk and adjust as necessary.
 
   / Bulldozer blade cutting angle #3  
I run Dozers for a living so I know this for fact. You must constantly be moving the blade to achieve a smooth cut, up and down basically non stop ( 1/2 inch up , 1/2 inch down , repeat repeat repeat..........). The more seat time you get the easier it will become. Slow and steady wins the race with a dozer. Try to slowly load your blade as you go over a distance , not in a 2 foot gouge will make your machine easier to operate.
 
   / Bulldozer blade cutting angle
  • Thread Starter
#4  
Mainly pushing dirt cleaning up exciting tracks cut into step country so lots of slips washouts and rutted out tracks to keep open one of the reasons New Zealand is so green is the high rain fall we get but it makes maintaining tracks on steep country hard work. The main point I am trying get answers to is on my Bobcat I can reduce the cutting angle which makes it much easier to keep moving forward with a controlled amount of dirt in the blade on the dozer with a sharper cutting angle once the blade cuts in the hydraulics’ don’t seem to have the power to raze it up and it dives in if you don’t stop to raise it
 
   / Bulldozer blade cutting angle #5  
It depends on the soil you are working in, and as far as the cutting edge angle, the rake is very close from dozers to scrapers, and road graders. The controls of the Chinese dozers are very coarse and don't lend well to the midwife touch (I changed all my controls over to Prince and Brand when I installed the top'n tilt TPH). Another issue to understand with these small dozers is the weight, and they are pretty light. I found that in working red clay set a light cut and leave the controls alone. If you're working glacial till then you have to constantly adjust the blade height. If you're working caliche, give the blade maximum down force. Never use any gear higher than 2H for dozing, and always push in a straight line (make the turn, then push) your steering clutches will thank you.

30HP Dozer also: http://www.youtube.com/watch?v=iOALrvSVYgc - YouTube

Pulling stump & backfill - YouTube

Hardpan - YouTube
 
   / Bulldozer blade cutting angle #6  
The main point I am trying get answers to is on my Bobcat I can reduce the cutting angle which makes it much easier to keep moving forward with a controlled amount of dirt in the blade on the dozer with a sharper cutting angle once the blade cuts in the hydraulics don稚 seem to have the power to raze it up and it dives in if you don稚 stop to raise it
As soon as you understand that a bulldozer was specifically designed to be a bulldozer, and a skid steer was specifically designed to be a loader you'll be on the right track. The geometry of of a dozer's cutting equipment does not even closely resemble that of a skid steer. You can get dozer attachments for the skid steer but that does not change their fundamentals of operation. In a nutshell: Don't try to operate the dozer like a skid steer. :) :thumbsup:
 
   / Bulldozer blade cutting angle #7  
First thing that I thought of when I read the first post was when I first started to operate my dozer. Always tried to take to big of a cut. Takes awhile to realize that you are not operating a D9. Takes a little bit of time to get a true feel for just what the machine will do in the conditions that you have. And of course the more experience that you get, normally you get much better at adapting to the conditions that you have to work with.

So take a lighter cuts and I think that you will have a much better outcome.

Good luck, and here's a couple of pics of my machine, just because, oh and my cutting edge looks to be just under 30*. ;)
 

Attachments

  • IMG_0516.jpg
    IMG_0516.jpg
    743.1 KB · Views: 1,559
  • IMG_0512.jpg
    IMG_0512.jpg
    780.1 KB · Views: 1,249
   / Bulldozer blade cutting angle #10  
 
Top