duck walking, what are the causes an what ways do you deal with it?

[Baker'sBackhoe]

just looking for feedback on what different factors cause duck walking and if anybody knows any good techniques to deal with it?

 

[Tinkerer]

Duck walking ??? Could you explain what the scraper is doing. Loaded or empty or both.

 

[scraperX]

pull up and restart your cut. you can also keep your apron low to minimize the depth of the duck walk.

gl

 

[oregon96pd]

Not sure, but im gonna guess that he's meaning the hop/bounce that they do at speed, like on the haul road. If thats the case then it's caused by the fact that the tires are six feet tall and have 30k plus pounds of weight on them...not a whole lot you can do about it. Maybe take it to the local tire shop and have them try to balance them

 

[Deeretracks]

Baby wipes work wonders to prevent duck walking, the cheap TP in jobsite Honey Buckets is problematic at best.

 

[DPete]

Best thing is to stop it right away, slow down if it's in the fill and raise up if in the cut. When the rear tires hit the first mound they cause it again and again like perpetual motion. It's frustrating, the only way to take it out is split your mark( straddle the bumps ) Some materials are worse than others, we used to run railroad iron drags in front of the rear tires to knock down the initial bump before the tires hit it.

 

[ShaneK]

Some scraper bowls have an automatic cushion ride system that works through the hydraulic accumulators to stabilize the machine. That or a cushion hitch may help prevent the duck-walk.

 

[Nige]

You can't use a cushion hitch in the cut or fill which is generally when the phenomenon presents itself.

 

[Baker'sBackhoe]

I think all the sand is making it worse cuz i usually dont have a prob with it. Does using the diff lock while cutting help? Also i think if i turn the cab about half a pass over, then back it seems to stop it. I'm just asking to see if that makes any sense, or is it just in my head?

 

[scraperX]

i like to use diff lock almost every load, but no, it doesnt affect the duck walk. dont load fast and shallow. if youre taking a thin cut, stay off the rear engine until you start to bog or lose traction (timing). if you start to duck walk soon after you begin to cut, pull out, wait till rear wheels pass, then restart cutting. and like mentioned above, dont keep your apron much higher than you need it.

welcome to dirt world

 

[Tinkerer]

Not sure, but im gonna guess that he's meaning the hop/bounce that they do at speed, like on the haul road.

I spent forty years in heavy and highway industry and never heard of duck walking. In the midwest of USA we always called it hop or bounce. Dpete and Shanes advice is spot on. Nige; you should see some of the idiots that I have seen in the cut and on the fill with the cushion hitch up. It is enough to bring tears to your eyes. There are ways to cure them of doing it, if you know what I mean Changing tire pressure can sometimes make a difference in the severity of the duck-walk.

 

[Nige]

One could always get unruly scraper operators back into line when you were triple-pushing 657s with 3 x D9G's. A few hard hits up the rear worked wonders.....

I recall way back when cushion hitches were first introduced. To the old-school scraper operators it was a sign of the world going soft.

 

[Shimmy1]

Even though this probably won't add much to the thread I'll still put in my $0.02. I've spent right around 5000 hrs on a Challenger with a JD 1810E pan cleaning drainage ditches in farm fields and know what duck walking is. I've found it caused by two things, one being more common. Hard packed sticky topsoil is the worst I feel. Ground that wants to come up in big slabs and leave holes for the tires to bounce through. Second could be more so referred to a washboarding but for the most part completely preventable is speed. Like ScraperX said slow, shallow, tight apron controls depth of cut to help prevent the slabbing. I know this might be controversial but if you're trying to cut final grade having a partial load in bowl helps. I do a lot of jobs start to finish with the scraper and when you're working by the hour if the last loads are not full loads it doesn't matter.

 

[Scrub Puller]

Yair . . .

I recall way back when cushion hitches were first introduced. To the old-school scraper operators it was a sign of the world going soft.

The first 627 I ran was a brand new stiff hitch. When the fleet of cushion hitches arrived no one wanted "old stiffy" but I didn't mind . . . no way could I run with the cushion hitches though with giving myself and the machine a beating.

I poked along and did my own thing mostly self loading, the fellers were good and set the cut up with good rills for me to grab.

If I was in the right place at the right time I got a bunt up the ass or could maybe grab a hook occasionally. I might have done a few less loads a day but the old girl paid her way.

Cheers.

 

[ShaneK]

A few more ideas that have been pondered for discussion:
1) Go into the cut at a much slower pace. Load the bowl about 1/4 - 1/3 full, once this weight is on the back tires, then ramp up the speed to lock in a large load.
2) Investigate welding "Skid Shoes" onto your scraper. This would enable you to hit the cut at your desired higher speeds, and help stabilize the bowl, and wheels from duck walking.

 

[637slayer]

i have learned that like mentioned, start digging with only your front motor until you get some dirt in there then floor em both, when dumping you have to be fast opening your lip and crowding out your dirt right away, matching your rpms to your ground speed, keep her rapped up. i use my tranny lock almost every time, locked in 2nd using front motor only. if ur moving too fast the initial blob that falls out when you open your lip, your back tires will go over it then there will be a gap before your back tires climb onto the dirt your crowding out. dump as deep as your biggest rock, one side hits a rock wile your dumping that starts a duckwalk , try to dump downhill, most important always split your tracks, if a duckwalk starts stop it asap, dont spread the disease! what scraper do you run?

 

[Buckethead]

what scraper do you run?

I can't answer for the original poster, but in the other thread he said he was running a 623 self loader. Don't know if he runs another one too.

 

[Baker'sBackhoe]

right now I am operating a 623. I run 627 and 637 as well, so i know what ur saying. My duck walking issue is happening when the dirt to dry or too wet. normally I like to cut in second but if I cut in first it's not so bad. dragging haul roads is the worst, is way too slow for that and still duck walks. And when the Phil starts to get bad if I even try to drag it smooth it just duck walks bad. I know I probably sound like a rookie but I'm really not, I'm just used to jobs where the right amount of water is importantand I never have a problem with duck walking

 

[still learn'n]

Yes know all about it and yes there is a solution they are call skid pads everyone of our scrapers have one of 2 designs on them! the one is a solid skid pad that is a foot or 2 behind the blade at the outside edge of the stinger bit that has shims that are adjustable! they get adjusted if the operator is not to lazy according to blade wear and or dirt type! The other is a hydraulic skid pad with a 6 inch cylinder on it with valves and tanks on them to control flow and extension! Jerry

 

[Baker'sBackhoe]

Id like to know more about the skid pads. Tried searching but no results on scrapers came up. U got any pics of them, or a link i can check out?