Building A small pull pan Type scraper

[earthface]

OK 5 4 3 2 1 ignition on boosters! We have lift off! NOT! Hey guys this aint rocket science we just need to move a little dirt here and there. Now I never planned it so that this thing get every last cc of dirt and every last once of HP out of any tractor. This scraper has a wide range of power consumption from about 20 to 40 HP now that is a w-i-d-e range of power. I am just talking of reviveing a 60 year old design from the grave. It works well and I belive is quite up to date still, maybe could use some fine tuning of the old one way (rise up fall down) hyds but that is about it. Its all there just need builders/users. Self loading, low power requirments, spot dumping, self leveling, short turning radius, quite easy fabrication using only farm shop tools standard of the shelf parts. What more could a user/builder ask for in a small scraper?? You tell me!
Thanks EF

Let's say that the lower drawbar is mounted 50 cm behind the rear axle, and 50 cm below the rear axle. The scraper holds 7 ton of dirt of which 2 is on the drawbar. The draft requirement equals the kerb weight of the empty tractor, which is 3,5 ton, of which 2 ton is on the rear axle and 1,5 is on the front axle. The axle heart distance is 2 meter (it's 2,14 meter on my 5245 but 2 meter is easier in this math.)
These are just estimations, close enough to real life scraping to get the general idea.

In the static situation, there is 2 ton at 50 cm behind the rear axle. That's 1ton/meter. At 2 meters from this point (the front axle) this will be 0,5 ton negative front axle load. 1000 kg will remain on the front axle.
This means roughly 4000 kg on the rear axle and 1000 on the front axle.

When the tractor pulls, there are two main points of force: the center of the rear axle, and the center of the drawbar eye. The tractor pulls with a force of 3,5 ton on this tow eye, and the corresponding lever is 50 cm, which causes a momentum of 1,75 ton/meter.
The result 2 meters further up front on the front axle, is 0,875 ton. The front axle load will be the 1000 kg, the outcome of the static calculation (at standstill) plus the dynamic force caused by the pull itself. this is 1000 kg plus 875 kg is 1875 kg on the front axle, and 4000 kg on the rear axle.
The static load index of the 5245 is 1800 kg up front and 3600 kg rear. That is the load to be bouncing on the road at 35km/h. At slow speeds (front loaders) the operators manual mentions a max. dynamic load at speeds below 10 km/h, of 2,5 times the static load rating. The tractor will do just fine, i just dont want to load my front axle that high because the bearing capacity is with front loader use in mind, not with heavy draft applications.

Off course there are loads of variables that have stood out of this calculation, like the reaction force of the wheel torque of the rear axle on the tractor body, which unloads the front axle, reaction forces in the front wheels etcetera. I hope you get the general idea, which is that any drawbar which is mounted higher or lower than the rear axle, causes a reaction force when the tractor starts to pull on this drawbar.

 

[MikeD74T]

earthface, Are you going to offer plans? How much? Mike

 

[Renze]

Earthface the rough calculations were to back my own plans, not yours...

Actually i'm thinking that my next project will be a straw bale chopper/bedder instead of a scraper... Maybe i'll hook up the 2 meter wide 3pt hitch bucket onto a dolly frame to use as a scraper, its cheaper and with a front gate, i would be able to hold 3 yards as well. A scraper is more fun, but a straw blower just has more use for me..

 

[earthface]

Heck I knew that, I just had to rib you a little as all that mech dynamics is WAY over my head, and most of the rest of the guys here too. It was just getting WAY to serious for a good BS session )

 

[earthface]

Iam using this scraper just now and having just to much fun playing in the big sand box to make the Drawing just now. But when the ground turns to a glacier I plan to draw it out. I havent got any Idea of price yet it is going to be plenty of work and I know that it cant be done for the $20 bucks that had been sugested earlier. There seems to be some demand for them but I bet it will be small. Will advise when done)
Thank you for your input and interest
EF

earthface, Are you going to offer plans? How much? Mike

 

[R W]

Owned a 1.5 cu yrd scoop 2 wheels, hyd lift,rope operated dump,
pulled it with a D46U or a 60HP Inter(564)(weight aprox 7500lbs)
wheel tractor.
From experience and conversation with other owners,It is my opinion
that at least 40HP per cu yrd is needed to handle these machines.
Providing you could rip the ground properly, when it became too hard
for the scoop to dig and kept at it, a lot of dirt could be moved.
The rope dump set up was utilised as most tractors only had one
hydraulic outlet in those years.

R W

 

[gtmacf]

That'd be a "Tumblebug"..doesn't need hydraulics.Just pull the rope or lever and it rolls foreward to dump! /forums/images/graemlins/grin.gif

Am trying to find out the make of my dads old tumblebug.
It is 42 inches wide,has a rope lever,a lever on hitch to level scraper while
moving to dump area.
Was yellow in color.
Thanks

 

[JimSealyJr]

I was wondering if anything ever came of this project?
I'd love to built a small pan for a 40-60 HP tractor.
Anything better than a pool scoop or toting dirt in the front bucket has to be an improvement, so I'm not looking for anything huge or too fancy or expensive.
Jim

 

[FarmWrench]

I ran into this after reading about R.G. LeTourneau and then finding a video of an Ashland scraper that looks identical to the OP. If anyone made something of this let me know.

 

[CNC Dan]

I ran into this after reading about R.G. LeTourneau and then finding a video of an Ashland scraper that looks identical to the OP. If anyone made something of this let me know.

Did you know that the last post to this thread was several years ago.