New project - 4WD Articulated Tractor

Bindian

Member
Mith,:wave:
Is that the seat your going to use? Seems a little high.
Awesome work and photo.:tiphat:
hugs, Brandi
 
N

Nicahawk

Guest
Mith...your just another genius working in dirty clothes!

Super job!
 

Mith

Active member
PB, had to steal my Dads camera. You dont realise how mad camera phones are till you use a proper camera. I'll buy one one day....

Brandi, yup, thats the seat. Its about the right height for the foot plates. I just thought of an idea to get the foot plates lower, so the seat can be lower. Cant make it too much lower or I wont be able to see the front.

Cheers Nica. I fully intend to go my whole life without wearing a suit, so far so good :D
 

quincy

Member
Are those tyres from a scissor lift Mith? They look the job. As for that seat, it does look a bit high but on the other hand it sure does looks COMFY and I guess when you build up around it it will look less out of place! Nice work on your progress so far, LOOKS GOOD!
Just curious about your plans for the machine. Are you thinking about mounting FEL and backhoe to that unit or just using it as a tractor?
 

Mark777

Member
Fascinating Project Mith! None even remotely like it that I've ever seen.

I’ve been staring at the monster in your picture (frame, wheels, seat) for a long while now and can visualize the completed project.

I’m sure the engine-power source predicament will present a solution in the very near future. It’s been a genuine treat to witness the transformation from idea, draft and build process for me…and surely most anyone following along. Keep plugging along and it will all come together.

Great tutorial, amazing pictures and I’ll be here to the end.

Mark
 

Mith

Active member
Q, they are actually brand new tyres, probably a similar type to those used on lifts though.
I think the seat looks higher than it actually is, it doesnt look odd up there. I would prefer it lower though. And yup, its real comfy, I've got one on my mower too :D
I might drop a loader on the front, and a 3 point on the back. If I get enough HP somewhere down the line I'll add another pump and a 540rpm motor on the back for a PTO.
My parents are moving house, and they'd like another loader so we can load stuff at one end and unload at the other. Putting stuff on pallets would be much faster than using boxes and moving them by hand.

Mark, I guess the only big visible bits to be added is the hood, steering wheel and maybe a little rear bodywork. With all the hydraulic plumbing it needs it'll probably look like an accident at a spaghetti factory on wheels.
3 pumps, 6 filters, 2 valve blocks, a steering valve, bunch of cartridge valves and diverters and a whole stack of actuators

Thanks guys, I'll get another photo when it looks different.
 

xPosTech

Member
Looks really good , Mith.

Those tires look like the ones on the little three wheeled loaders that the delivery trucks from the lumber yards carry around with them. They fit on the back of the trailer and use the lift arms to raise themselves up for transport.

Will the tires not hold air at all? I remember your trick for seating the bead. Did they ban you from that stairway?:yum::yum:

Ted
 

Mith

Active member
Cheers Ted.
I ended up tubing them, getting the beads on was still a hassle, and luckily they havent banned me from the steps as I had to use them again to get them to seat :D Works like a charm I tell you!

All the frame is welded, a little paint and I'll bolt it together, then its pumps and engine time. I'll sort some pictures in the next couple days....
 

waughd

New member
Hi Mith
possible dumb question
are the hydraulic motors equipped with sufficient bearings etc for the strain of wheels being bolted straight to them or am I missing something?
I have not had anything to do with these beasties before.
Great project BTW
Des
 

Jim_S

Super Moderator
SUPER Site Supporter
Gold Site Supporter
Hi Mith
possible dumb question
are the hydraulic motors equipped with sufficient bearings etc for the strain of wheels being bolted straight to them or am I missing something?
I have not had anything to do with these beasties before.
Great project BTW
Des

Des,

WELCOME TO THE FORUM!
 

Mith

Active member
Thanks Des.
You can specify 'wheel motors' that come equipped with the necessary bearings to support the load. I think the option cost me $50 more per motor.
Normal motors wont take more than a couple lbs shaft side load, these take in excess of 1600lbs.
Welcome, stick around, cheers
 

SPYDERLK

Member
Thanks Des.
You can specify 'wheel motors' that come equipped with the necessary bearings to support the load. I think the option cost me $50 more per motor.
Normal motors wont take more than a couple lbs shaft side load, these take in excess of 1600lbs.
Welcome, stick around, cheers
Thats straight radial weight isnt it? What about axial thrust and bending torque on the shaft causing it to bow on side hill type work?
larry
 

Mith

Active member
Larry, the radial load on the shaft obviously depends on how far out the load is from the wheel motor mount. I made my rims offset so they are centered over the motor mount, so they are good for their maximum rating.
I cant remember the max thrust load, but its more than enough for the machine.
I could find the shaft load torque graph if you want to take a look.
 

waughd

New member
Thanks for the warm welcome
More questions if I may
Any chance you can find time to give full size details for the tyres?
Are you willing to share wheel motor details?
This is one interesting project.
Des
 

SPYDERLK

Member
Larry, the radial load on the shaft obviously depends on how far out the load is from the wheel motor mount. I made my rims offset so they are centered over the motor mount, so they are good for their maximum rating.
The side thrust force multiplied by the radius of the wheel is what concerns me. This force applied inward or outward on the tire contact causes a pretty large bending torque on the motor shaft at the bearing. The problem would be more and more severe as you went to bigger diameter wheels. Do the motor specs deal with that parameter at all?
larry
 

waughd

New member
Mith
I am concerned with just 1600lbs per wheel.
Bear with me as a newb and used to metric to as well.
I assume your beastie will weigh in at around 4000lb when completed.
That it will be roughly balanced front to rear by the time engine is fitted and bucket/loader is fitted.
This puts approx 1000lb on each wheel at rest.
If my understanding is correct any load added to the front by bucket or forks would put double that on the front axle
you have 1200lb spare on front axle with both at 600 spare so are limited to 600lb lift at rest.
Any movement acceleration/deceleration forces would need to be added to this calc and effectively reduce load capacity.
Perhaps someone can check/verify or correct me on this.
I need to have this right for when I go through the process myself
Des
 

Mark777

Member
Welcome Des,

I’d like to toss in some of my own observations:

I can’t speak for Jim, but I can say that critical specifications like the wheel motors must meet certain criteria and tested before they can be listed and sold. Here, and much of the rest of the globe, the governing body would be ASME. They will have been tested for close tolerance gear lash, end play and spindle shear strength.

Since the (Mith’s) design centers the wheel to the spindle the proposed 1600#.s X 2 seems well within the assigned duties of his tractor.

If these hydraulic motors are even remotely built like the ones used in industrial environments like fork-lift trucks, both warehouse and yard models, which are commonly used beyond their designed capabilities and are subjected to severely uneven loads, side impacts and roll over’s…and still continue to perform for years, I’m somehow confident they are more than adequate for his tractor.

You’ve brought up some interesting points and hypothetical circumstances but I’m reminded (from my background in controlled deformation) that the burden of weight, lateral forces and impact is not on the motors alone. Telegraphed stresses will be shared and evenly distributed throughout the fame. And then there is the human factor. Most any operator, even with limited experience, can and will react to a loader bucket that’s over filled. Usually, uneven or overloaded balance is instantly communicated to the operator by loss of rear counter balance, loss of rear traction or our own inner ear telling us the laws of gravity are being challenged.

Just my thoughts and my two cents worth :D

Mark
 

Mith

Active member
Des, the tyres are 26x12x12, carlisle tru power brand. 4 or 8 ply, I cant remember.
The motors are 315cc/rev capacity, 850Nm torque @200 bar.
Ask all the questions you want, they prompt me to think about things I have otherwise overlooked.

Larry, the only specs I have is the shaft load chart. To be honest, I have only really dusted over the calculations, I just bought the strongest motors I could afford. I believe they are up to the job, I would have liked to get something with plenty of extra capacity but the cost could have spiraled out of control.
I compared the specs to other machines to decide if they would do the job in real life usage. Once machine in particular was 4000lbs and used motors not much more substantial to what I have. He has many hours on his with no wheel motor problems.

Des, I'll talk in metric then (saves me converting :D)
I'm shooting for 1000kg machine weight, maybe 1200. 300kg lift on the loader and 3 point linkages would be fine, my other loader lifts 250kg and I haven't been left wanting for more. In terms of the linkages, 300kg will allow me to put a 5' mower on there.
So with an implement front and rear at the capacity of the linkage I'm at 1800kgs max. Assuming its balanced thats 450kg per motor, which is below the 800kg allowed load, and should allow for dynamic forces (I think the motors stated specs allow for this too) and if its unbalanced.
Are you planning a similar machine? In terms of wheel motors, if you can afford them the White RE series are the motors to have. They are around $500 each though.
 

waughd

New member
Mith
That's fine I was not sure just what you were shooting for.
I have seen a similar sized commercial unit that can lift 2400kg it uses dedicated bearings for wheels and motors jut provide drive.
Thanks for info and putting up with me, I am a way off with mine I have a major project currently under way that needs finishing first.
Des
 
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