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Tractractor

What do you do with your Quadratrack?

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Max horsepower  is a constant while torque is not. a 500 hp Ferarri will put out 2000 ft lb of torque if it is geared down. Torque is changed every time you shift gears. You say the Quad has 38000# and 450 hp? I have 50,000# with huge tracks and 290hp. Unfortunately long ago Deas Plant told me that my 290 HP engine  would tear up my finals so I'm going to have to pass on the pull-off.  Could I win with a 9HP Briggs geared down sufficiently? Probably, but I would need some ballast to replace the engine weight lost with the Briggs. What would win is weight and related traction, not horsepower. Let's see, I have about 12 ft. lb of torque with the Briggs so I need a 166 to 1 gear reduction to get 2000 ft lb. Yes it would be a slow tractor but it would pull !

=======================

According to my manual the 24 will pull 41,985 lb in first gear. That sounds about right since most crawlers have a tractive effort off around 85% of their weight. The quad would have to pull with 105% of it's weight to equal that. That is the basis for my logical win. (on paper)

How about we try something new and compare two machines of equal weight and equal power with equal gearing. Lets get away from the brands and model comparisons and compare quad versus crawler? This way we'll figure out which is more productive in a day.

Lets pull them both to their absolute traction limit in the lowest gear, what ever it is determined to be. Not sure how we should run the track width yet, but lets maybe use the same width tracks on each unit, but allow the track frame lengths to be respective to the chassis design for the weight of machine. Or we could use the standard width tracks for the given weight of machine. I imagine this would give the quad about 25% or so more ground contact area. Which in turn will reduce the psi but the design of the chassis is what we should compare.

Where do we go from here? I think we should pull them in a usual situation, with some steering needed. How would you compare these two machines in this given situation? Which one will pull more and why? And how would you , or anyone else, come up with your answer? This could be a fun comparison. I'd hope to keep it freindly.

That is if its ok with Tractractor, it is his thread.

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R Cubed

If a guy took those old adds serious

He would be in serious trouble.

They don't tell you that in real work

situations ,that you need another TD24

to help the first one to load.

Weight is what hurt the TD24.

On a uphill push it took a lot of power

just to pull itself. Soft ground worked

it hard too.

I have watched those old 24's work

quite alot. On a steep grade out of a

lake bottom,they needed a push cat.

They would pull it on their own,but it

worked them too hard. With a loaded

can on a grade they would overheat.

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OHH, a topic that is near and dear to me...I run a CAT 865 Challanger and pull 2 pans, fully loaded I hual amy where from 30 to 40 yds. depending on materal and loading conditions. We also run CAT 627 as well it depends on the job which one is used or which one works best.

post-73-1123716860.jpg

BTY It is rated at 550 hp.

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could not get pounds pull at the drawbar for the quadtrack!

what i did get is even better, a 9380 quad is 360HP at flywheel.

they rate them at 321HP at drawbar!

need i say more!

my money is and will remain on the quad!

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Someone said the quad weighed 38,000 lb. If that is the case I would be surprised if it could muster 41,985 lb of tractive force. This is the main basis for my logic. This is a case of physical laws, traction and weight, not hocus pocus technology.

Does anyone have statistics on it?

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I would add for those that don't understand what horsepower is and how it works. If your tractor has twice the drawbar HP that mine does that means you can pull the same force twice as fast OR the same speed with twice the force. Horsepower is time/speed related. (force times velocity) I don't need 321 HP to beat it just more traction. If I can pull you backwards at 1/2 MPH, I win.

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Someone said the quad weighed 38,000 lb. If that is the case I would be surprised if it could muster 41,985 lb of tractive force.  This is the main basis for my logic.  This is a case of physical laws, traction and weight, not hocus pocus technology.

Does anyone have statistics on it?

So you're saying that a tractor cant pull more than its own weight?? Is that what you believe to be true?? If so, how did you come to this conclusion?

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Empirical, my friend. I've looked at spec sheets of lots of tractors and find they almost all can pull at about 85% of their weight and this depends on having a dry nominal dirt surface. To exceed this you would need something to give a positive grip like a cog railroad, for example. In that case traction doesn't depend on friction with the surface. My 2 inch growsers act something like the cog railroad and probably better than rubber ones would. Aren't there any other diehard IH fans here besides me? If someone produces reliable data that the quad can pull more than it's weight then I will shut up.

:wacko::(

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The quad has 5 or 6 thousand pounds

of weights added to the dry factory weight.

Also with the way it is designed ,the tow

point is high enough to transfer weight to

the tracks without lifting the front.

The harder it pulls the more weight gets

transfered to the tracks.

If you raise the tow point on the TD24,

it will transfer the load to the sprockets,

and you will loose traction.

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Someone said the quad weighed 38,000 lb. If that is the case I would be surprised if it could muster 41,985 lb of tractive force.  This is the main basis for my logic.  This is a case of physical laws, traction and weight, not hocus pocus technology.

Does anyone have statistics on it?

So you're saying that a tractor cant pull more than its own weight?? Is that what you believe to be true?? If so, how did you come to this conclusion?

I don't want to keep adding fuel to the fire here, but what about a 12,000# semi tractor pulling a 80,000# load?

- It's all about traction & resistance ;) .

IH RD

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Sawmill, did you ever read abut Henry Ford's traction experiments??

He found that under a plow load, the 8N achieved more additional traction by putting 100 pounds on the front wheels, than it did by putting three hundred on the rear wheels.

Same concept with the quadratrack. The additional weight on the front of the tractor is multiplied by the length of the frame, as the weight of the implement being towed tries to lift the front of the tractor. The harder it pulls, the more traction it gets.

When I hauled cars out of baltimore, we used to use this same concept. If somebody got a low body trailer hung on a curb, you generally couldn't pull them off with another bobtail. However, if you hooked the chain to the car rack over the cab, it formed a sort of lever that tried to pick up on the front of the pull vehicle, thus transferring weight to the drives, providing enough traction to move the stuck object.

Same reason you can drive a two wheel drive pickup, up a hill you cannot back up. It all has to do with driveline angles and weight transfer.

My money's on the quad.

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If you start adding weight to the quad the bet's off. My theory is based on a straight pull on a surface like they use at tractor pulls, just dry dirt drawbar to drawbar, no fancy tricks.

As for a 12,000 pound truck pulling a 46,000# tractor that's rolling resistance and has nothing to do with ground friction. A strong man can push a railroad car weighing many thousands of pounds. No I don't think it's possible to get a tractive effort equal or greater than tractor weight on dirt, you can on certain kinds of pavement. That's how dragsters get accelerations greater than 1G and formula 1 cars can corner at 3G's. What would the speed of a top fuel dragster be on dirt? Anyhow I don't see any advantage in a weight shift on a 4 wheel drive setup and I assume the Quad has 4 "wheel" drive. Why would you want to take weight off the fronts which are pulling?

The way I see it the bigest advantage to the quad is being able to pull a lot of plow bottoms at speed (horsepower), and having rubber tracks that don't tear up the road like mine does. (and of course an air conditioned cab) Disadvantages are obvious, there's one on ebay now (TD24) for $1600. Figure on your quad at 100+ times that amount.

I repeat, no diehard IH folks out there? KoO, where are you?

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Psycho

You just said what I was trying to say.

With the extra weight on the nose of

the quad and a higher pull point .

The harder it pulls ,it transfers more

weight to the tracks,same thing as Fords

discovery.

The TD24 pivots on the roller frames. If

you raise the pull point on it .It will raise

the nose of the cat transfering the weight

to the sprockets. All the TD 24 has is the

dead weight on the tracks for traction

when both tracks are flat on the ground.

When a crawler is overloaded on the

sprockets you lose traction.

I load trucks for extreme conditions and

under stand traction pretty well.

The 12,000 pound empty semi tractor,

will barely pull its self for traction.

When loaded to 80 thousand pounds

with the trailer ,The drive tires weigh

34 thousand ,the steering 12,000 and

trailer 34,000.

It becomes a 46,000 pound tractor pulling

a 34 ,000 pound trailer.

We always move our loads ahead for slick

or loose roads,hence sliding fifth wheels.

I wouldn't bet either way on a pull off.

If R cubed locked his brakes, I think the

quad would be in trouble.

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I think I see the falacy here. There is no way that a 38,000 lb tractor can shift weight that will end up putting more than 38,000 lb on the tracks unless you actually add weights! In the case of the Ford we are talking about a 2 wheel drive where weight shift IS critical as we want very little weight on the front idler wheels, just enough to steer. Also, with the 3pt hitch the plow in the ground can essentially add weight to the tractor's rear wheels by pulling it downward.

You can raise or lower the height of the drawbar to shift weight but whatever you do it will not be able to put more than 38,000 lb on its 4 paws. I would think the best traction would be had with equal weight on each of the four. A shift of weight to the rear would be counterproductive and make them spin in the dirt.

post-275-1123783575.jpg

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R-Cubed, take a tape measure out to your 24 and measure from the drawbar hole to the center of the sprocket, and then from the drawbar hole to the.......radiator. You could go to the bell housing or any point up front, then do the same thing to an equivalent quad. On the quad you go from the drawbar hole to the rear track frame pivot, and then from the drawbar hole to the radiator. Or see if you can find the quad specs online and get them aproximate that way.

Even with just those measurements, you should see what Sawmill and others are saying about the weight transfer. Its not added weight or transfering weight from the work load, its simply power applied against a lever. Thats over simplifying it, but it should show you why the quad has this advantage. Hopefully.

The engine and front track undercarriage on the quad are out further on the lever that is fulcrumed at the rear track frame pivot. The 24's fulcrum is the center of the sprocket. The counter lever is the distance from the drawbar hole to the fulcrum on each machine. Are you following my jibberish so far?

To go further, which I will confuse you and I even more, would be to measure up from the ground to the fulcrum centers and the drawbar hole to the ground. Are you starting to see where this is going yet?

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I have no idea where you are going. Shifting weight is fine on a Farmall H or a dragster but it serves no purpose on a tracked or 4WD vehicle. What can you gain by taking weight off one drive wheel and putting it on another? This is a different situation than pulling a sled at a tractor pull. I'm pretty sure I could do a full pull with any sled now in existance. (now we can argue about that!)

:rolleyes::rolleyes:

post-275-1123810107.jpeg

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die hard IH fans?

R Cubed, if that was a green tractor you took the tug o war shot at i would not say anything.

suitcase weights are a factory option, they list them plus the brackets to hang them in the parts manuals. a BC 290 is not a factory option for the 24.

you mention the cleats as an advantage on the 24. in a pull against the quad thay will cost you traction. the quad has a lug design commonly refered to as chevrons. tractor tires utilize this design also. they are far superior to a straight lug due to the fact that the straight lugs plug up with material when slippage is encountered. the chevron V design moves the material to the outside so as to get a firm footing for the next lug.

as for the quad, the drawbar pins about six inches behind the pivot pin.

take a ford 8N and chain just the drawbar to a powerpole. let the clutch out and it will flip over on its top. then take the chain and wrap it around the front axle center, you will kill the engine when you let the clutch out, when you load the tractor, it actually pulls the tractor down (tractive forces).

if a quad track has 321HP at the drawbar, how are you going to win in a pull with less than 290HP at your drawbar?

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What can you gain by taking weight off one drive wheel and putting it on another?

fr = Fr/N.

Reducing the surface area (Fr), increases the coefficient of friction(fr).

We used to pull the outside wheel off the dual rears on the dump trucks, to plow snow in the winter.

The only thing increased surface contact gives you is weight distribution, and flotation. Flotation does not equal traction by any stretch.

Why do you think the wide tracked machines are called Low Ground Pressure machines.

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I have no idea where you are going. Shifting weight is fine on a Farmall H or a dragster but it serves no purpose on a tracked or 4WD vehicle. What can you gain by taking weight off one drive wheel and putting it on another? This is a different situation than pulling a sled at a tractor pull. I'm pretty sure I could do a full pull with any sled now in existance. (now we can argue about that!)

First off a dozer are made to push with . A quad track is made to pull with. If you have ever run a dozer you would know that dozing with a dozer wieght tranfers all the time as you adjust the blade to keep the track all on the ground raming the blade into the ground takes wiegth off the front of a dozer and make the back part of the tracks do the pushing and then you just spin track till you level out the tractor again. It the same hitching to the drawbar you pull down on the drawbar on a dozer and take traction from the tractor by lifting the front part of the tracks. Take it from a old dozer man say away from the quad track heel make you look like a fool in a pull. Pushing is a different story you will make a quad track look like a fool. Bob

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wow this is great, i have tried to get a topic like this going on the BB for the last year. the quad tracs were used on the cat trains to the south pole, they out pulled the cat rubber track machines hands down.

keep it going boys

thansk

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"horsepower is inconsequential?"

You guys that think he can beat me on horsepower alone here this. Some friend of no.2 son was showing off in his 4WD truck on our farm a few years ago and got it stuck in the mud. The only thing I had running at the time was a Case VAC which is a 2 bottom smallish wheel tractor. I bought it for $35 with a blown engine and put a 9HP Briggs in it to do odd jobs. With this I pulled him out of the quagmire. I repeat- tractors are meant to get TRACTION. High horsepower tractors are meant to do things faster.

The Ford tractor that gains weight and traction is a good story but where does the extra downforce come from? The only place it can come from is the pulling chain or plow. It's weight is a constant and gravity won't change it just for this case. In Statics and Dynamics 101 class we would draw a free body diagram if not sure how all the forces were acting. It is my intention to connect the chain at a point where there is NO weight shift since I don't want to take traction away from the front half of the track. It's true that straight growsers tend to dig like a trencher but it has to spin to do that and with my 12,000 lb advantage I should just blow him away.

Yuk! Yuk!

BTW, we won't be pulling each other in the snow. As I said ... on dry dirt. (if my growsers dig deep enough to hit bedrock I should gain an advantage)

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"horsepower is inconsequential?" 

You guys that think he can beat me on horsepower alone here this. Some friend of no.2 son was showing off in his 4WD truck on our farm a few years ago and got it stuck in the mud. The only thing I had running at the time was a Case VAC which is a 2 bottom smallish wheel tractor. I bought it for $35 with a blown engine and put a 9HP Briggs in it to do odd jobs. With this I pulled him out of the quagmire.  I repeat- tractors are meant to get TRACTION. High horsepower tractors are meant to do things faster.

The Ford tractor that gains weight and traction is a good story but where does the extra downforce come from?  The only place it can come from is the pulling chain or plow. It's weight is a constant and gravity won't change it just for this case. In Statics and Dynamics 101 class we would draw a free body diagram if not sure how all the forces were acting.  It is my intention to connect the chain at a point where there is NO weight shift since I don't want to take traction away from the front half of the track. It's true that straight growsers tend to dig like a trencher but it has to spin to do that and with my 12,000 lb advantage I should just blow him away.

Yuk! Yuk!

BTW, we won't be pulling each other in the snow. As I said ... on dry dirt. (if my growsers dig deep enough to hit bedrock I should gain an advantage)

Thats just it R-Cubed, the power applied is the transfer of the weight. The foward thrust against the pull "transfers"?? the weight leverage into traction.

In the example of the 8n, pulling from the drawbar, there is more than enough traction and power to lift the front off the ground and possibly flip the tractor. By hooking the chain under the tractor and to the front axle, the pulling force on the chain now keeps the front from raising. If the frontend cant raise, then more power is applied to the rear tires. As more power is applied to the rear tires, the chain gets tighter keeping the front end down even more, which applys more power to the rear tires, and so on, and so on, untill the traction limit of the rear tires with this added "transfer" of power into weight, or the power limit of the engine is met. This works when hooking the chain straight out from the drawbar with no downward angle as well.

Any better??

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You are right if the chain starts out low enough that it can pull the front DOWN and you have a 2WD tractor. I don't see how that would help the quad. His chain if we can find a big enough one, will be coming from my drawbar which isn't low enough to help him.

Who said crawlers are made to "push"? Pulling 27 yard scrapers was what my klunker was made for. (extra long track with 26" pads) Not to mention KoO and his Cat-trains.

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You guys are getting way too high tech.

Now for a hillbilly solution. :D:D

If a 300 pound man grabs a 140 pound

mountain lion by the tail. The lion can out

pull the man. If it turns around it can sure

out push him. :D:D

The lion does'nt weigh as much,but it can

get all the traction it needs.

If Cats were designed to only push.

Why were dozers added years after they

were invented. I have been using the wrong

machine I guess. Ninty percent of the work

I have used a cat for is pulling.

Skidding logs,pulling rippers,root plows,trucks,

scrapers,disc,oil rigs,and a few other things.

KoO is going to have to start pushing sleighs! :D:D

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