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pushloading scrapers
- Thread starter ozscooper
- Start date
pushkid84
Well-Known Member
push loading
in my time pushi loading i found that it is best to always pick up the scrappers on the run dont let them stop in the cut i think it is more productive that way have the scrappers cut in lines next to each other and have the only make shallow cut do this the entire lenght and width of the cut area and then go back to the start and begin again this generally leaves a nice clean cut area i was always told that the dozer hand is in charge of the cut so make sure that the scrapper hands are traveling on the shortest path and that they know how you want them to make thiere cuts, also try to hook up with them smoothly or they my gouge just to **** you off good luck to you.:usa
in my time pushi loading i found that it is best to always pick up the scrappers on the run dont let them stop in the cut i think it is more productive that way have the scrappers cut in lines next to each other and have the only make shallow cut do this the entire lenght and width of the cut area and then go back to the start and begin again this generally leaves a nice clean cut area i was always told that the dozer hand is in charge of the cut so make sure that the scrapper hands are traveling on the shortest path and that they know how you want them to make thiere cuts, also try to hook up with them smoothly or they my gouge just to **** you off good luck to you.:usa
Turbo21835
Senior Member
Ive never pushed with a d8. The crew i was working on had Terex Ts14bs and was pushing with a D7h or D6R. The rules of the spread are simple. The guy on the dozer runs the cut. You may have time between scrapers to rough grade the area by eye. When it comes to the, I would push the until the cut gets too heavy for the dozer, and then i feather that blade of dirt out. The pan operators then know thats where to start the cut when they come back.
When it comes to running the cut, I try to have the scraper make a pass, then skip just shy of a scraper width, and make another cut. This leaves a windrow inbetween the last two cuts. The next pass they pick up that windrow. It looks something Similar to this ___---___ It is easier to keep the cut even that way, and its easier to load while picking up the windrow.
When it comes to pushing. I always sit just to the left of where i want the scraper to come in. My rule is, never go by me on the left, as the 7H and 6R have the seat angled to the right, that means my left rear corner tends to be a blind spot. I sit at an angle, as the scraper comes by me I start moving once the left rear passes the corner of my blade. I try to push in 2nd gear. The scrapers need to be in the cut in 1st, otherwise, they tend to run away. When making contact with the stinger, I have my blade as high as I can. That way you catch the bottom of the stinger with the cutting edge, it makes a smoother pick up. If you notice the stinger is curved, the same as your blade, like this )). Once you make contact with the stinger, I drop the blade, this locks the back end of the scraper down. One a double barrel, that means the rear tires have better traction. It also means the front of your tracks wont ride up, therefore, more of your tracks stay on the ground and maintain better traction
When it comes to running the cut, I try to have the scraper make a pass, then skip just shy of a scraper width, and make another cut. This leaves a windrow inbetween the last two cuts. The next pass they pick up that windrow. It looks something Similar to this ___---___ It is easier to keep the cut even that way, and its easier to load while picking up the windrow.
When it comes to pushing. I always sit just to the left of where i want the scraper to come in. My rule is, never go by me on the left, as the 7H and 6R have the seat angled to the right, that means my left rear corner tends to be a blind spot. I sit at an angle, as the scraper comes by me I start moving once the left rear passes the corner of my blade. I try to push in 2nd gear. The scrapers need to be in the cut in 1st, otherwise, they tend to run away. When making contact with the stinger, I have my blade as high as I can. That way you catch the bottom of the stinger with the cutting edge, it makes a smoother pick up. If you notice the stinger is curved, the same as your blade, like this )). Once you make contact with the stinger, I drop the blade, this locks the back end of the scraper down. One a double barrel, that means the rear tires have better traction. It also means the front of your tracks wont ride up, therefore, more of your tracks stay on the ground and maintain better traction
Renfroe Grading
Well-Known Member
Once you make hard contact with the push block put the blade in float.
always start next to the slope so you and your scrapers have a straight line to go by, the fastest way to push scrapers is called chain loading. thats where the pushcat pushes out a scraper then backs straight up leaving enough room so the next scraper can swing in get straight and start digging where the previous scraper left off.
cat scrapers and dozers match up well in second gear if the scraper pulls in at a 45 angle in 2nd gear when his back fender is almost past your dozer start moving pick em up in second wait till he bogs you down a bit shift into first to finish off his load, depending on the dirt scrapers should not take more than 30 sec. to load. 15-2o sec. is ideal. most important get into a routine, if the scraper isnt locked into second and he outruns you then stops tell him once then give him the hammer, if they pull in and sock it in the dirt, tell them once then give them the hammer, dont ride the brakes for no one. when that rear fender goes by your dozer there should be one puff of smoke from your cat, until you back up.
cat scrapers and dozers match up well in second gear if the scraper pulls in at a 45 angle in 2nd gear when his back fender is almost past your dozer start moving pick em up in second wait till he bogs you down a bit shift into first to finish off his load, depending on the dirt scrapers should not take more than 30 sec. to load. 15-2o sec. is ideal. most important get into a routine, if the scraper isnt locked into second and he outruns you then stops tell him once then give him the hammer, if they pull in and sock it in the dirt, tell them once then give them the hammer, dont ride the brakes for no one. when that rear fender goes by your dozer there should be one puff of smoke from your cat, until you back up.
thanks for all the tips, most of my pushin has been 51s with a 11 on downhill faces about 50 meters long and pushin on the run didnt work there so i never was able to try it. now im on the old 8 pushin 21s building dams with nice long loading and i just cant get the production i want. so i think i will try the on the run style and see how it works. the dozer driver before we was not very good at all and had taught the scoop drivers a lot of bad habits which made it very hard for me. but this time around i will have 4 guys who have never driven scoops so i be able to teach em my ways. and as for givin em a hammer ive got a real good style for doin that but you gotta really upset me before i do that. i dont like bein hit when im on a scoop and you better have a good reason for hittin me.
While I greatly prefer twins due to their superiority, I’ve spent plenty of time around singles and push-cats.
First off, you’ve received a lot of good advice so far. I’ll second what Renfroe Grading said, putting the blade in float once you make contact with the stinger is important, it greatly decreases wear on the blade of the push-cat and the wear plates on the scraper.
As always, regardless how experienced one of the scraper hands may be, or thinks he is, the push-cat operator runs the cut. Every scraper does as he signals.
A few basic signals: The push-cat hand will raise his right or left arm and hold it visibly in the back window to signal which side he wants the scraper to come in on. If the scraper has left his ejector forward, two fists with thumbs up are placed together (thumbs pointing apart) as the scraper passes the push-cat to let him know to get on the ejector to get it back. If the push-cat wants the operator to load out a windrow, he’ll place his hands straight with his arms and hold the finger tips together to create a pyramid shape with his arms/hands to signal this.
I hope that makes sense?
I also like to see the push-cat drop his rippers slightly while pushing, if done with discretion, this won’t decrease load times on the scraper being pushed, and will increase overall load times in the cut.
Make sure the grade checkers (assuming they’re using GPS rovers) always stake the cut in straight lines working with the angle the scrapers are cutting. As the scrapers cut down and the stakes get a few feet high onto long ridges, the grade checkers had better be on top of it to get stakes halfway in between the previous lines so the scrapers can start loading out the ridges.
Based on the material and the push-cat, I set a spec time for loading. This number will really be gleaned from experience.
Say a D10R pushing 631E’s in gravelly material. Load times shouldn’t be over 18 seconds, and I want to see material over the sideboards in that time frame. I’ll cut a new guy slack for a little while, but if he can’t consistently load in less than 18 seconds and have material over the sideboards, I replace him.
The guys that get in are heaped and off the push-cat in 12-14 seconds are the ones who get raises.
I’ve often told new scraper hands to start counting as soon as the push-cat makes contact, start at one-Mississippi and if they’re not well loaded by 15 (or whatever time fits the situation), they need to improve.
This also seems to help get them into the rhythm of lifting their can and closing the apron around 14-16 seconds so they’re pulling off the push-cat in a consistent 18 seconds or less. This keeps things fluid and increases production.
Second, every scraper should be picked up on the move. If the haul’s gotten short, the fill-cat stopped the scrapers and they all got to the cut at once, than they’d better be can-dragging the windrows to clean up and grade the cut up to the push-cat, or wheel-rolling the windrows in the cut which will increase load times (this is only if the cut is large enough to prevent this from becoming a clustermuck).
I won’t tolerate a scraper sitting in the cut waiting to get pushed. If a scraper comes into the cut, drops his can and waits for the push-cat, I’ll have a little chat with him, if he does it again, he’s done.
Ideally, with an adequate sized push-cat, the scraper should be dragging into the cut in 1st or 2nd gear (depending on material and size of push-cat) and have at least 2-3 yards rolling up into the can when the dozer makes contact. This alone can shave 2-3 seconds off load times.
Once you get a few hands used to working with their push-cat, good operators can get this down to a science. In the right circumstances I’ve seen excellent operators load above the sideboards in less than 10 seconds.
Another thing you might want to look into to increase production is build supers into the turns on the haul roads. As long as your cut and fill aren’t changing too rapidly, giving you a pretty constant haul road, any sharp turns should have a good super built into them.
On big fills, I routinely have the scrapers build a stock pile at the end of the fill, perpendicular to the direction the scrapers are hitting the fill. I’ll then have a dozer carve out a big Nascar style turn into the side of it, and a blade feather it out perfectly.
On big long term fills, I won’t flinch to put 30,000-50,000 cubic yards into the pile to create the super. Give it a nice gradual contour from the flat of the fill up onto the turn and back. It allows the scrapers to hit the fill at full speed, dump as fast as possible which makes for level filling which aids compaction and decreases compaction machine’s workload. The scrapers can then continue balls out for the super, hit it and be headed back across the cut to the fill without ever slowing down.
This also really helps on canyon fill-ins where the scrapers have to climb elevation to get back to the cut.
While this may increase haul distance by a few hundred feet (the scrapers won’t turn around immediately after dumping), haul times are drastically reduced because the scrapers never having to get off the throttle.
Also, the sidewall flexing from tires making flat turns is greatly decreased which in turns greatly increases tire life. That alone makes a big difference in cost by the end of the job.
As the fill builds, the big super will become a hole, so I’ll have my biggest utility cat(s), preferably D10’s stay late one night with the compactor and water pull, push the material into the hole and compact it. So far every geotechnical inspector I’ve worked with has overseen this operation and as long as there’s adequate compactive effort while tearing the super down, I’ve had zero complaints.
The next day I’ll have the scrapers build a new stockpile, and that night, or the next night, depending on the amount of material needed, I’ll have one of the mid-sized finish cats stay late with the blade and build a super into the side of the stock pile to continue the fast cycle times of the scrapers.
Anywhere on the haul road that there’s a turn, and often at turns into cuts, I build supers as well. This is especially true with twins, which greatly benefit from hitting the fill at high speed.
Hell, on some tight schedule jobs I’ve painted the brake pedal every Monday morning and told the scraper hands that anyone who’s worn that paint off by Friday can find a new job.
Everyone who works for me knows that the scrapers need to be the ones moving full speed all times. It’s everyone else’s job to support this and make it happen. I take the speed of my scrapers seriously.
First off, you’ve received a lot of good advice so far. I’ll second what Renfroe Grading said, putting the blade in float once you make contact with the stinger is important, it greatly decreases wear on the blade of the push-cat and the wear plates on the scraper.
As always, regardless how experienced one of the scraper hands may be, or thinks he is, the push-cat operator runs the cut. Every scraper does as he signals.
A few basic signals: The push-cat hand will raise his right or left arm and hold it visibly in the back window to signal which side he wants the scraper to come in on. If the scraper has left his ejector forward, two fists with thumbs up are placed together (thumbs pointing apart) as the scraper passes the push-cat to let him know to get on the ejector to get it back. If the push-cat wants the operator to load out a windrow, he’ll place his hands straight with his arms and hold the finger tips together to create a pyramid shape with his arms/hands to signal this.
I hope that makes sense?
I also like to see the push-cat drop his rippers slightly while pushing, if done with discretion, this won’t decrease load times on the scraper being pushed, and will increase overall load times in the cut.
Make sure the grade checkers (assuming they’re using GPS rovers) always stake the cut in straight lines working with the angle the scrapers are cutting. As the scrapers cut down and the stakes get a few feet high onto long ridges, the grade checkers had better be on top of it to get stakes halfway in between the previous lines so the scrapers can start loading out the ridges.
Based on the material and the push-cat, I set a spec time for loading. This number will really be gleaned from experience.
Say a D10R pushing 631E’s in gravelly material. Load times shouldn’t be over 18 seconds, and I want to see material over the sideboards in that time frame. I’ll cut a new guy slack for a little while, but if he can’t consistently load in less than 18 seconds and have material over the sideboards, I replace him.
The guys that get in are heaped and off the push-cat in 12-14 seconds are the ones who get raises.
I’ve often told new scraper hands to start counting as soon as the push-cat makes contact, start at one-Mississippi and if they’re not well loaded by 15 (or whatever time fits the situation), they need to improve.
This also seems to help get them into the rhythm of lifting their can and closing the apron around 14-16 seconds so they’re pulling off the push-cat in a consistent 18 seconds or less. This keeps things fluid and increases production.
Second, every scraper should be picked up on the move. If the haul’s gotten short, the fill-cat stopped the scrapers and they all got to the cut at once, than they’d better be can-dragging the windrows to clean up and grade the cut up to the push-cat, or wheel-rolling the windrows in the cut which will increase load times (this is only if the cut is large enough to prevent this from becoming a clustermuck).
I won’t tolerate a scraper sitting in the cut waiting to get pushed. If a scraper comes into the cut, drops his can and waits for the push-cat, I’ll have a little chat with him, if he does it again, he’s done.
Ideally, with an adequate sized push-cat, the scraper should be dragging into the cut in 1st or 2nd gear (depending on material and size of push-cat) and have at least 2-3 yards rolling up into the can when the dozer makes contact. This alone can shave 2-3 seconds off load times.
Once you get a few hands used to working with their push-cat, good operators can get this down to a science. In the right circumstances I’ve seen excellent operators load above the sideboards in less than 10 seconds.
Another thing you might want to look into to increase production is build supers into the turns on the haul roads. As long as your cut and fill aren’t changing too rapidly, giving you a pretty constant haul road, any sharp turns should have a good super built into them.
On big fills, I routinely have the scrapers build a stock pile at the end of the fill, perpendicular to the direction the scrapers are hitting the fill. I’ll then have a dozer carve out a big Nascar style turn into the side of it, and a blade feather it out perfectly.
On big long term fills, I won’t flinch to put 30,000-50,000 cubic yards into the pile to create the super. Give it a nice gradual contour from the flat of the fill up onto the turn and back. It allows the scrapers to hit the fill at full speed, dump as fast as possible which makes for level filling which aids compaction and decreases compaction machine’s workload. The scrapers can then continue balls out for the super, hit it and be headed back across the cut to the fill without ever slowing down.
This also really helps on canyon fill-ins where the scrapers have to climb elevation to get back to the cut.
While this may increase haul distance by a few hundred feet (the scrapers won’t turn around immediately after dumping), haul times are drastically reduced because the scrapers never having to get off the throttle.
Also, the sidewall flexing from tires making flat turns is greatly decreased which in turns greatly increases tire life. That alone makes a big difference in cost by the end of the job.
As the fill builds, the big super will become a hole, so I’ll have my biggest utility cat(s), preferably D10’s stay late one night with the compactor and water pull, push the material into the hole and compact it. So far every geotechnical inspector I’ve worked with has overseen this operation and as long as there’s adequate compactive effort while tearing the super down, I’ve had zero complaints.
The next day I’ll have the scrapers build a new stockpile, and that night, or the next night, depending on the amount of material needed, I’ll have one of the mid-sized finish cats stay late with the blade and build a super into the side of the stock pile to continue the fast cycle times of the scrapers.
Anywhere on the haul road that there’s a turn, and often at turns into cuts, I build supers as well. This is especially true with twins, which greatly benefit from hitting the fill at high speed.
Hell, on some tight schedule jobs I’ve painted the brake pedal every Monday morning and told the scraper hands that anyone who’s worn that paint off by Friday can find a new job.
Everyone who works for me knows that the scrapers need to be the ones moving full speed all times. It’s everyone else’s job to support this and make it happen. I take the speed of my scrapers seriously.
Deas Plant
Senior Member
Pushing scrapers.
Hi, Ozscooper.
Most of the advice given above will work in one situation or another. Basically, it is what works for you in the particular sitaution that you are working at the time. Sorry I can't help with a video. Maybe the description below will do.
My favoured method of picking up a scraper is to have them pull past me on whichever side I am angled to until the push block is about one dozer length, give or take a bit, in front of my downstream corner tip, the side on which I will be pushing the scraper to. See Fig. 1.
I start moving as soon as the scraper is past me, pulling across the back of the scraper and aiming to put the corner tip closest to the push block right under the push block with the cutting edge at the same height as the bottom of the push block. See Fig. 2.
As the corner tip touches the push block, I start to turn the blade under the push block making a sliding contact with the push block as the blade straightens up behind it. See Fig. 3.
The cutting edge of the raised blade, being angled back from the push block, helps this sliding contact and reduces any shock loading and jolting. As the contact begins to firm up and the scraper starts moving, begin lowering your blade so that the push block slides up the face of the blade to be cupped by the roll of the moldboard. This lowering of the blade can be done as part of the turning in behind the push block, once you get the 'feel' of it.
You can get an approximation of this by closing one hand into a fist and holding it facing directly across your body, fingers and palm facing down. Now bring your other hand up, palm open and angled back at about 45 degrees so that the bottom back corner of your palm, directly under your thumb contacts the near corner of your closed fist with the bottom edge of your open palm at the same level as leading knuckles of your closed fist. Now slide your palm towards you, turning it as it slides much like a dozer blade would as it turns under the push block in the manner described above. At the same time, let the knuckles of your closed fist slide diagonally up the palm until your palm is directly behind your closed fist and at right angles to it, just like the dozer blade in the attached sketches. Get the picture?
This method only works with a straight or semi-U blade. It does not work with an angle or 'U' blade as there is a rather large risk of spearing a scraper tyre. Timing and coordination are EVERYTHING but it is the fastest way I know of picking up a stopped scraper. When you get your hand and your eye in, you can pick them up on the run in second gear at full throttle and NO bump.
With an angle or 'U' blade, I still pick them up with the cutting edge at the same height as the bottom of the push block when using an 8H or 8K. 'cos you can still see over the blade. I just do it square on from behind.
As the load comes on and you slow down to a bit below first gear's top speed, downshift into first, complete the loading and upshift into 2nd again to boost the scraper on its way.
The D8H, along with the D9G, are my favourite push-loading tractors because I find the separate clutch-nad-brake steering smoother and easier to judge my turns with than the later integrated types. Even with a D8K or D9H, I would use the clutch lever AND the brake pedal for my turns when picking up scrapers. Then again, maybe I'm a dinosaur. But I'm a happy one.
I disagree with one member who advocated putting the blade in float once you have made contact. I always like to keep a little weight on the blade to aid traction. You can also control the cut of a scraper to a certain extent if it is cutting heavy on one side by tilting your blade up on that side. If you WANT to make it cut heavy on one side, tilt the opposite side of your blade up. This will also help with steering if you have to make a cut on a turn. Tilt the blade down on the side you are turning to.
I prefer to always keep the outside edges of my cut low as it is hard for a scraper to get up on a high, in-sloping edge and stay there while loading but it is easy to take a high centre down. On the other hand, it pays to keep the outside edges of a fill high to help stop scrapers sliding over the edge as they dump. I only raise the middle of a fill to facilitate drainage if rain is likely.
Hope this helps.
Hi, Ozscooper.
Most of the advice given above will work in one situation or another. Basically, it is what works for you in the particular sitaution that you are working at the time. Sorry I can't help with a video. Maybe the description below will do.
My favoured method of picking up a scraper is to have them pull past me on whichever side I am angled to until the push block is about one dozer length, give or take a bit, in front of my downstream corner tip, the side on which I will be pushing the scraper to. See Fig. 1.
I start moving as soon as the scraper is past me, pulling across the back of the scraper and aiming to put the corner tip closest to the push block right under the push block with the cutting edge at the same height as the bottom of the push block. See Fig. 2.
As the corner tip touches the push block, I start to turn the blade under the push block making a sliding contact with the push block as the blade straightens up behind it. See Fig. 3.
The cutting edge of the raised blade, being angled back from the push block, helps this sliding contact and reduces any shock loading and jolting. As the contact begins to firm up and the scraper starts moving, begin lowering your blade so that the push block slides up the face of the blade to be cupped by the roll of the moldboard. This lowering of the blade can be done as part of the turning in behind the push block, once you get the 'feel' of it.
You can get an approximation of this by closing one hand into a fist and holding it facing directly across your body, fingers and palm facing down. Now bring your other hand up, palm open and angled back at about 45 degrees so that the bottom back corner of your palm, directly under your thumb contacts the near corner of your closed fist with the bottom edge of your open palm at the same level as leading knuckles of your closed fist. Now slide your palm towards you, turning it as it slides much like a dozer blade would as it turns under the push block in the manner described above. At the same time, let the knuckles of your closed fist slide diagonally up the palm until your palm is directly behind your closed fist and at right angles to it, just like the dozer blade in the attached sketches. Get the picture?
This method only works with a straight or semi-U blade. It does not work with an angle or 'U' blade as there is a rather large risk of spearing a scraper tyre. Timing and coordination are EVERYTHING but it is the fastest way I know of picking up a stopped scraper. When you get your hand and your eye in, you can pick them up on the run in second gear at full throttle and NO bump.
With an angle or 'U' blade, I still pick them up with the cutting edge at the same height as the bottom of the push block when using an 8H or 8K. 'cos you can still see over the blade. I just do it square on from behind.
As the load comes on and you slow down to a bit below first gear's top speed, downshift into first, complete the loading and upshift into 2nd again to boost the scraper on its way.
The D8H, along with the D9G, are my favourite push-loading tractors because I find the separate clutch-nad-brake steering smoother and easier to judge my turns with than the later integrated types. Even with a D8K or D9H, I would use the clutch lever AND the brake pedal for my turns when picking up scrapers. Then again, maybe I'm a dinosaur. But I'm a happy one.
I disagree with one member who advocated putting the blade in float once you have made contact. I always like to keep a little weight on the blade to aid traction. You can also control the cut of a scraper to a certain extent if it is cutting heavy on one side by tilting your blade up on that side. If you WANT to make it cut heavy on one side, tilt the opposite side of your blade up. This will also help with steering if you have to make a cut on a turn. Tilt the blade down on the side you are turning to.
I prefer to always keep the outside edges of my cut low as it is hard for a scraper to get up on a high, in-sloping edge and stay there while loading but it is easy to take a high centre down. On the other hand, it pays to keep the outside edges of a fill high to help stop scrapers sliding over the edge as they dump. I only raise the middle of a fill to facilitate drainage if rain is likely.
Hope this helps.
Attachments
Pushed some 631C's with a D9H.
3 pushers and 9 scrapers. There was an excellent pushcat hand that taught us young guys his ways. We were production, not cutting grade and here is how we did it;
Pushcat is pointed straight where he wants scraper to cut.
Scrapers typically came in at 90 degrees to the cut, were pushed downhill to load going towards the fill, and the cut was worked side to side evenly with 1 pushcat on each side and 1 in the middle.
Scrapers typically worked with the same pushcat.
Scraper coming in at 90 degrees would shift to second and do a 90 degree turn in front of pushcat at about 1/2 throttle, leaving his rear tires square in front of the blade. Scraper should let off throttle a bit more and start skimming and slowing down until he feels just a bit of a speed increase and he'll know the pushcat has picked him up. If scraper stops before he is picked up he probably outran the pushcat by taking off to fast after turning. If he does stop he Should Stay Stopped.
Pushcat shifts into second as scraper turns in front of him. Due to the turn radius of the scraper tractor the rear tires are traveling slowly and it is easy to creep up smoothly on the stinger. As the scraper straightens from the turn ease into contact with the stinger. Here was the hardest thing to learn, be traveling at the same speed but accelerating, when you touch the stinger if you are at the same speed and accelerating the scraper is not jarred at all, from the scraper you just notice a slight rise in speed.
On downhill cuts with the D9H's and 631C's we never had to drop to 1st, good hands didn't even slow you down in 2nd and got real nice loads. Downshifting jars the scraper so I try to avoid that.
Another good reason for scrapers to come in at 1/2 throttle and the deaccelerate is to avoid spinning the scraper drivers, a big no-no.
The reason a scraper shouldn't take off after he stops is the pushcat probably was very close to picking him up when perhaps suddenly the scraper stops, so pushcat locks up to not bump him, then ease forward to pick him up gently.
IF the scraper keeps trying to move he will probably take off before the pushcat makes contact, and so now the pushcat is chasing the scraper and the process repeats itself making an easy thing very hard.
Running a single load long cut if there is a another scraper coming in he should set himself in the cut and wait for you to back up and get him.
If you have time you should back the pushcat in 2nd at about 1/3 throttle to your next waiting position.
Doing production correctly you should not be dozing at all. Moving dirt in the borrow with the dozer just costs money and isn't necessary.
Sitting and waiting patiently is the most cost effective.
Don't hit scrapers on purpose. You want your scrapers to work for you and with you.
These dozers had the pushin-cushin blade and we used the top of it where the cushion was, the hinge was on the bottom.
On a straight or u blade raising the blade does help to reduce the straight on shock of the blade down lower. After contact it depends on the blade on whether or not you have to just ease it down some or can hit float. On some dozers throwing it into float and letting the blade move suddenly down can jar a scraper. Once or twice ain't bad, but after the 60th load or so that day it gets pretty old if your on the scraper.
3 pushers and 9 scrapers. There was an excellent pushcat hand that taught us young guys his ways. We were production, not cutting grade and here is how we did it;
Pushcat is pointed straight where he wants scraper to cut.
Scrapers typically came in at 90 degrees to the cut, were pushed downhill to load going towards the fill, and the cut was worked side to side evenly with 1 pushcat on each side and 1 in the middle.
Scrapers typically worked with the same pushcat.
Scraper coming in at 90 degrees would shift to second and do a 90 degree turn in front of pushcat at about 1/2 throttle, leaving his rear tires square in front of the blade. Scraper should let off throttle a bit more and start skimming and slowing down until he feels just a bit of a speed increase and he'll know the pushcat has picked him up. If scraper stops before he is picked up he probably outran the pushcat by taking off to fast after turning. If he does stop he Should Stay Stopped.
Pushcat shifts into second as scraper turns in front of him. Due to the turn radius of the scraper tractor the rear tires are traveling slowly and it is easy to creep up smoothly on the stinger. As the scraper straightens from the turn ease into contact with the stinger. Here was the hardest thing to learn, be traveling at the same speed but accelerating, when you touch the stinger if you are at the same speed and accelerating the scraper is not jarred at all, from the scraper you just notice a slight rise in speed.
On downhill cuts with the D9H's and 631C's we never had to drop to 1st, good hands didn't even slow you down in 2nd and got real nice loads. Downshifting jars the scraper so I try to avoid that.
Another good reason for scrapers to come in at 1/2 throttle and the deaccelerate is to avoid spinning the scraper drivers, a big no-no.
The reason a scraper shouldn't take off after he stops is the pushcat probably was very close to picking him up when perhaps suddenly the scraper stops, so pushcat locks up to not bump him, then ease forward to pick him up gently.
IF the scraper keeps trying to move he will probably take off before the pushcat makes contact, and so now the pushcat is chasing the scraper and the process repeats itself making an easy thing very hard.
Running a single load long cut if there is a another scraper coming in he should set himself in the cut and wait for you to back up and get him.
If you have time you should back the pushcat in 2nd at about 1/3 throttle to your next waiting position.
Doing production correctly you should not be dozing at all. Moving dirt in the borrow with the dozer just costs money and isn't necessary.
Sitting and waiting patiently is the most cost effective.
Don't hit scrapers on purpose. You want your scrapers to work for you and with you.
These dozers had the pushin-cushin blade and we used the top of it where the cushion was, the hinge was on the bottom.
On a straight or u blade raising the blade does help to reduce the straight on shock of the blade down lower. After contact it depends on the blade on whether or not you have to just ease it down some or can hit float. On some dozers throwing it into float and letting the blade move suddenly down can jar a scraper. Once or twice ain't bad, but after the 60th load or so that day it gets pretty old if your on the scraper.
RollOver Pete
Senior Member
I've always been careful about putting my blade in the float position since a little incident that happened to me years ago on a E.L. Yeager dirt spread.
This one day a dozer and a push cat hand that rode together were not going to make it to the job.
I think they had grenaded the engine in their car...
Anyways, they were a no show.
Our foreman starts moving people around so he can keep both 57 and 51 spreads going.
He leaves one of the utility cats in the yard and takes me off of a 57 to go push 51's.
Bill Kelly was one of their regular push cat hands...he'd been pushing scrapers since the beginning of time.
This old man was good.
I had run a push cat for Dudley many times in the past and he knew Bill and I worked good together.
We would both push 51's...
We would alternate who would come in first.
If I was on the scraper and Bill was pushing me, as soon as I'd lift my left hand Bill would throw it in reverse while I finished with my push.
Bill would then pick up the next 51 and I'd come in behind him.
When he waved me off, I'd back up and pick up the next 51.
This worked out great.
I would have my blade in float until the scraper was loaded.
At that point I'd grab a gear with my left hand, take her out of float and wave Bill off.
Y'all know the black plastic dome looking thing that is at the bottom of the blade control on some of the older Cats.
When they get worn they sometimes hang up....
Well, with me pushing a 51, blade in float and the 51 about ready to grab a gear is when it happened.
Pushing in 2nd, I had just grabbed 3rd gear.
While pulling back on the blade control I thought to myself, "self...this don't feel right".
Since I was fighting with the stupid blade control I had not given Bill the signal to back off.
As the scraper pulls away, the blade hits the ground while Bill is still pushing.
It's amazing how fast a narrow blade behind 2 D10N's will dive on you.
I still kind of think Bill did it on purpose...
After all, I had not waved him off so like the good push cat hand that he was, he just kept the coals poured to her.
Not that it was that big of a deal.
I'm sure the 51's were wondering what in the hell was going on.
Even though that was almost 20 years ago,
I still think about it every time I throw the blade in float while pushing a scraper.
This one day a dozer and a push cat hand that rode together were not going to make it to the job.
I think they had grenaded the engine in their car...
Anyways, they were a no show.
Our foreman starts moving people around so he can keep both 57 and 51 spreads going.
He leaves one of the utility cats in the yard and takes me off of a 57 to go push 51's.
Bill Kelly was one of their regular push cat hands...he'd been pushing scrapers since the beginning of time.
This old man was good.
I had run a push cat for Dudley many times in the past and he knew Bill and I worked good together.
We would both push 51's...
We would alternate who would come in first.
If I was on the scraper and Bill was pushing me, as soon as I'd lift my left hand Bill would throw it in reverse while I finished with my push.
Bill would then pick up the next 51 and I'd come in behind him.
When he waved me off, I'd back up and pick up the next 51.
This worked out great.
I would have my blade in float until the scraper was loaded.
At that point I'd grab a gear with my left hand, take her out of float and wave Bill off.
Y'all know the black plastic dome looking thing that is at the bottom of the blade control on some of the older Cats.
When they get worn they sometimes hang up....
Well, with me pushing a 51, blade in float and the 51 about ready to grab a gear is when it happened.
Pushing in 2nd, I had just grabbed 3rd gear.
While pulling back on the blade control I thought to myself, "self...this don't feel right".
Since I was fighting with the stupid blade control I had not given Bill the signal to back off.
As the scraper pulls away, the blade hits the ground while Bill is still pushing.
It's amazing how fast a narrow blade behind 2 D10N's will dive on you.
I still kind of think Bill did it on purpose...
After all, I had not waved him off so like the good push cat hand that he was, he just kept the coals poured to her.
Not that it was that big of a deal.
I'm sure the 51's were wondering what in the hell was going on.
Even though that was almost 20 years ago,
I still think about it every time I throw the blade in float while pushing a scraper.
Attachments
slope was pretty soft in those pics, i liked the scoops to be lifting out after 20 secs and gone by thirty, most times the boys were good but got the odd "clingon".
when i first started on the 51s we had a "dozer legend" pushing us he hit me three times in 4 loads third hit knocked me out. no reason just a heap of excuses but i found out later he was using mobile phone. same bloke hit another fella who was a ex champion jamacian boxer and boy was there some fireworks. the only word comin from his mouth that wasnt swearin was kill. they sacked the dozer boy a week later
when i first started on the 51s we had a "dozer legend" pushing us he hit me three times in 4 loads third hit knocked me out. no reason just a heap of excuses but i found out later he was using mobile phone. same bloke hit another fella who was a ex champion jamacian boxer and boy was there some fireworks. the only word comin from his mouth that wasnt swearin was kill. they sacked the dozer boy a week later
sometimes thats a delicate relationship between pushcat hands and scraperhands, when i first started pushcat guy would point down to dig deeper, when they point over and down that meant if you got a problem with the way im doin this lets get in the dirt. i seen a couple altercations over dirt in the cut, sometimes pushcat wars would make a day fly by, if i was in a 41 or 51 with their huge fans and the metal fins angled the engine air to the side, i would drive by the pushcat with it rapped up, he was on a bald 9, just to watch him grab his hat when the temp outside was hot and the engine heat really hot, he would look away and shield his face, in front of him i tried to never come to a stop.
Deas Plant
Senior Member
On Paint And Speed
Hi, MassX.
While I agree with you on most of your points, you have also told me that I just plain wouldn't work for you. For mine, anybody who'd pull your stunt of painting the brake pedal and firing anybody who wore it off oughtn't be in charge of anything more dangerous that a chook raffle. The brakes are there for a reason, to aid in controlling the machine and operating it safely.
I also think that it is good to work to support the speed of the scrapers but, again for mine, it HAS to be within the constraints of safety, an aspect that you did not mention. The whole object of safety on a site is to have as many able-bodied people leave the site at the end of a shift as entered it at the start of the shift, without having to replace anybody. The same could be said for the machines in the spread, allowing for breakdowns.
Just my 0.02.
Hi, MassX.
While I agree with you on most of your points, you have also told me that I just plain wouldn't work for you. For mine, anybody who'd pull your stunt of painting the brake pedal and firing anybody who wore it off oughtn't be in charge of anything more dangerous that a chook raffle. The brakes are there for a reason, to aid in controlling the machine and operating it safely.
I also think that it is good to work to support the speed of the scrapers but, again for mine, it HAS to be within the constraints of safety, an aspect that you did not mention. The whole object of safety on a site is to have as many able-bodied people leave the site at the end of a shift as entered it at the start of the shift, without having to replace anybody. The same could be said for the machines in the spread, allowing for breakdowns.
Just my 0.02.
9420pullpan
Senior Member
one thing that you can do to prevent the initial hit when approaching the push block is to try and contact the push block just above the cutting edge and as the blade makes contact with the block it will roll up into the center of the blade.
i learner this from a dozer hand in CA.
i have seen and FELT alot of dozer operators use the center of the blade, but once you try and make contact with the bottom and let it roll up you will see it is much easier for the dozer operator and less painful for the pan operator.
i hope this makes sense
i learner this from a dozer hand in CA.
i have seen and FELT alot of dozer operators use the center of the blade, but once you try and make contact with the bottom and let it roll up you will see it is much easier for the dozer operator and less painful for the pan operator.
i hope this makes sense
N.CarolinaDozer
Senior Member
- Joined
- Sep 21, 2007
- Messages
- 377
- Location
- Granite Falls, NC (U.S.A.)
- Occupation
- Heavy Equipment Operator
I have nothing wrong with scraper operator's but the dozer operator is in charge of pushing. If I push pans, they have to do it my way or I'll sit there until they understand me. I let one pan sit still for 30 minutes one time, and the foreman came flying up in his truck cursing us with every word he could think of.:cussing I explained to him I wasn't going to chase pans all around the cut. I also said if they dont stay tight in rows he could find a new pusher. I expect the pans to stay beside each other in rows and the next one to be pushed should be ahead of us being ready. I hate when I'll be pushing one and have to back up 50 to 100 yards to push the next one waiting. Common sense is all it takes, but it seems the one's we have never get it, even though I explain it to to them muitiple times.ointhead To keep the load counts high, both dozer and pan operator's have to work together! And understand each other how there is a right way to cut. Lucky thing is I dont have to push anymore, now that I fine grade and work slopes, so now that our pushman's problem.:woohoo
ointhead To keep the load counts high, both dozer and pan operator's have to work together! And understand each other how there is a right way to cut. Lucky thing is I dont have to push anymore, now that I fine grade and work slopes, so now that our pushman's problem.:woohoo+1 deas, i dont know how much scraper massx has run but safety is first. mass x i noticed you said pull in front of the cat in first or second, cat scrapers do not naturally shift into first, to get into first is a manual shift.
i use first for when i get stuck, pulling something out, or coming off a really steep slope. im not above shifting c,d, model scrapers manualy but the newer scrapers with the trany locks so convenient i very rarely shift manually.
i hope you werent suggesting the cat rip while pushing?
i use first for when i get stuck, pulling something out, or coming off a really steep slope. im not above shifting c,d, model scrapers manualy but the newer scrapers with the trany locks so convenient i very rarely shift manually.
i hope you werent suggesting the cat rip while pushing?