Jump to content

Archived

This topic is now archived and is closed to further replies.

Tractractor

What do you do with your Quadratrack?

Recommended Posts

Just hook the winch line up to the quad and start pulling when the 24 digs in and can not pull the quad, engage the winch and suck him in as a cat with a winch can pull twice its weight. :D

Share this post


Link to post
Share on other sites

Old Pokey

The quad and the lion are the same.

Sudden burst of speed = horse power

Lion able to shift weight to paw or paws

that needs it . Same with quad.

Lion able to put power to paw with most

traction. Same with quad ie differentials.

They are alike in several ways.

The quad can't develop its full energy

and lift from a standstill.

It is designed to develop its torque and

traction once the tracks are moving.

R Cubed is right about the weight of the

TD24. The weight in the books are for a

bare dry machine. When you add all the

hardware, the weight goes way up.

If he held the brakes ,it would take a

D10 to slide those grousers through hard

dirt from a straight drawbar pull.

It would be like trying to push a large

stump through the ground with your dozer

at ground level.

Once the quad spun or pulled down,he

could walk away with it.

All he would have to do is hold it for a

bit with the clutch to get the same effect.

In a plowing contest once the quad got

rolling it would run away from the TD24

with the same size plows. The quad

would be building power and traction

after the 24 had maxed out.

Share this post


Link to post
Share on other sites

their is no advantage to weight shifting in the big 4 wheel drive tractors. they do not shift weight anyway, the harder you work them (pull on drawbar) the greater the force down on the drivers.

trust me, i have spent hours in the cab of a 9380 wheel tractor plowing! when you drop your plows down you can feel the machine sink. this is because the work being done is below the tractor itself. when plowing you are around 10 to 12 inches below the bottom of the tires. this is trying to pull the drawbar down to centerline which would be around 5 to 6 inches below the ground. but it cannot pull the drawbar down to this level due to the eight tires. so the load is just transfered back to the ground as increased weight. throw the clutch, the weight disappears

in the ford/versatille manual i remember reading about the tractors weight. they balanced it at a 60 40 ratio. 60% of the machines weight on the front and 40% on the rear. they mention when you load the tractor to its full capacity, you gain 20% on the rear.

R Cubed,

back to the briggs.

lets say we found a common ground as far as friction is concerned!

do you think a quad would drag a 24 with the tracks locked up?

i think it would.

would a 24 drag a quad with the tracks locked up?

i think it would also!

a 5HP briggs in a 24 with a 166 to 1 reduction in revs to maintain pounds pull at drawbar, by my calculations gets you 50 feet an hour in low gear!

drop the clutch and you would not notice anything happening at that instance!

a quad at full throttle in low gear will travel around 5280 feet an hour. drop the clutch on this at full throttle in low gear and you travelled 7 inches in a second.

the brigged out 24 traveles .166 thousandths of an inch a second.

the quad travels 7 inches a second. what would happen if the two were pinned together at the drawbar?

Share this post


Link to post
Share on other sites

Here we go again with the horsepoweritis thing. Brute pulling force doesn't have speed as a factor. I can pull a Quad backwards with a 1/4 HP electric motor runnng a winch hooked to a big oak tree. It's true that the both machines hooked to a 15 bottom plow that the quad would run off and hide thanks to the horsepower. Im glad to see that we put the weight shift thing in it's proper place.

And I am using a 9HP Briggs not a 5HP. Am gearing it 166 to one to the tranny input shaft and it gets another 20/1 reduction after that in the tranny, etc. Yes, I think that would be a pulling giant but would take all day to get across the barn floor. :blink:

Share this post


Link to post
Share on other sites

Incidently, this part of your statement needs further study.

"their is no advantage to weight shifting in the big 4 wheel drive tractors. they do not shift weight anyway, the harder you work them (pull on drawbar) the greater the force down on the drivers."

What you say is true if you are pulling something like a plow that pulls the rear end DOWN. That would of course add apparent weight/downforce on the driving wheels giving it more traction. My TD24 is not a plow and the chain would make it a horizontal pull adding zero to your traction. In fact you would lose traction as I pulled you aft at 1/2 MPH!

:lol:

Share this post


Link to post
Share on other sites
Pokey, I realize you are just pursueing theory here but getting back to reality, I see no advantage to weight shifting on a 4WD tractor like the Quad. If there is one I wish someone would explain it.

That's what I'm sort of attempting to do. Its tough to do with our only means of communication being typeing on the internet. But in my spare time I'll continue to find a way to bring proof to you of what I know to be fact. In the mean time I'll just continue to look like a fool. :D Believe me, I am an expert at that. :P

At least now I know you understand the weight transfer. All I need to do now is find a way to prove that a certain amount of the force that caused the weight to transfer, also is added to the downforce (weight) of the tractor when pulling. Even if the pull is straight off the drawbar. But...........I do have to say I was still just making assumptions about drawbar heighth. You probably allready know something about your drawbar being a lot higher than the quad or something and are keeping that as your ace in the hole. :D

There are also many more variables that have to be taken in to the final equasion before the pulloff can be won on paper. One being the "tractive force" equasion. Traction and tractions ability to maintain itself is one. Since you'll be pulling on dirt, the dirts friction force at the edge of the tread lugs is another.

Anyway, this is fun, for me anyhow. I'll keep trying. :)

Share this post


Link to post
Share on other sites
:blush::blush::blush: I may have just came to the realization that in a "pulloff" the added force would be divided between the 2 machines, and would then be useless. I had it stuck in my mind that each machine would pull an unpowered object, even though I aknowledged a "pulloff". :blush: Like I said, I am good at looking the fool. :blush:

Share this post


Link to post
Share on other sites

In order for there to be any advantage in traction due to the pulling effect there would have to be a vertical component to the chain. If the chain was perfectly horizontal then neither tractor would get that benefit. If you hitch him low and me high I would tend to lift his rear end when the chain pulled tight making him lose traction. (if it didn't make me go over backwards)

This would be a true battle of the titans! Good thing it's just on paper. :o

Share this post


Link to post
Share on other sites

R Cubed,

i believe you are right!

after going through pokeys last link that shows the concepts of traction equation i see your point. the other equations are dealing with rear drive wheeled tractors, things dont work out there for a quad. but the tractive force equation would be the same for the quads.

in this equation velocity is not an issue, for some reason i had velocity as the key to the whole deal! the sad thing of all this is at one point 10 to 12 years ago i knew all this when i was looking into the designs of the wheel

tractors vs tracked tractors and their capacities, but had since forgot. after seeing the equation it all clicked and now again i know, and am sure i will soon forget. its a vicious circle!

you do realize though in a tug o war we would get the option of accesorizing the quad with the same accessories as your 24. this would dictate a front mounted blade (never seen one on a quad but have seen them on the wheeled versions) and a heavier engine (preferably out of a locomotive). this would even the playing field.

Share this post


Link to post
Share on other sites

The last thing I need is a "even" playing field. My 2" growsers and extra weight are my unfair advantage. Take them away and I would lose. This would be like pitting an F86 against an F15 with a 40 year advantage in technology.

:blush:

Share this post


Link to post
Share on other sites

Take two 24's chained together one with 200 hp the other with 500 hp. while the lesser just churns up dirt the high hp one will

move a huge quanity of dirt at high speed. This is called friction traction vs. lugging traction. The Horsepower does make a difference.

Share this post


Link to post
Share on other sites

The 200 horse TD 24 would win by default.

Because when you dumped the clutch on

the one with 500 horses. It would become

a 50,000 pound TD 24 jigsaw puzzle.

Share this post


Link to post
Share on other sites

:lol:

That's a good one Sawmill.

BTW, are you really a pirate like your picture would indicate?

Share this post


Link to post
Share on other sites

R -Cubed

I have been called worse. :D:D

Now put your glasses on and look

at the picture.

The picture is Geronimo. Famous

old Apache leader,and medicine man.

Come to think of it,he was kind of a

pirate too. :D:D

Share this post


Link to post
Share on other sites

I've been wondering about the speed/traction situation from the start since the quad will undoubtably have a higher low gear. There can be something signifcant about speed and traction, I know this for a fact. Swap situations to dune buggies. It's common knowledge in those circles that you can have too BIG of a tire if you want to go faster. A small(low hp) engine cannot use a big tire do to not being able to "pull" it. As you go up the hp spectrum you also go up in tire, further the hp a bunch more and you can accelarate faster by going to a vastly smaller tire. The phenomen of moving the sand faster with tire speed instead of traction. It may have to do with gaining "traction" by pushing against the mass of the sand instead of the friction from moving from rest. Wondering if since this situation is true, might there be a different type of traction difference betwen the quad and crawler?

Share this post


Link to post
Share on other sites

Sorry R cubed. Just looked at the Nebraska test website, and I think you'd get wumped. An STX 440 is roughly equivalent to a 9380 quad, although probably slightly heavier. It weighs 50,000 lb UNBALLASTED. Max drawbar pull listed is 38,412 lbs in 3rd gear at 2.9 MPH, they don't show any lower than that because those gears aren't typically used in an ag tractor. You are correct, HP is a function of speed. You are however, incorrect, in that there isn't any weight transfer on a straight DB pull with the quad track. The hitch point is in front of the rear tracks and signifigantly below the center of pull of the machine. It's also ballasted at 60% or more weight to the front. Now, if you want to compare your tracked machine to a quad that weighs exactly the same and only pull in low gear, you might have a chance, but you'd better never slip a track and let him start gearing up on you or you'd be done for :D

Chads

Share this post


Link to post
Share on other sites
I've been wondering about the speed/traction situation from the start since the quad will undoubtably have a higher low gear. There can be  something signifcant about speed and traction, I know this for a fact. Swap situations to dune buggies. It's common knowledge in those circles that you can have too BIG of a tire if you want to go faster. A small(low hp) engine cannot use a big tire do to not being able to "pull" it. As you go up the hp spectrum you also go up in tire, further the hp a bunch more and you can accelarate faster by going to a vastly smaller tire. The phenomen of moving the sand faster with tire speed instead of traction. It may have to do with gaining "traction" by pushing against the mass of the sand instead of the friction from moving from rest. Wondering if since this situation is true, might there be a different type of traction difference betwen the quad and crawler?

Changing the tire sizes in your equation effectively changes the final drive ratio's .

Chads

Share this post


Link to post
Share on other sites

I didn't say you couldn't have weight shift in a Quad since you can have a weight shift/transfer in ANY tractor. I was just saying that it didn't seem to be any advantage to take weight off one set of drivers and add them to another set. Nobody has been able to explain how that would help.

No, I don't want to pull against any "almost 9380" that weighs 12,000 lb more. That was one of my unfair advantages, remember? Even then the 38,000 lb tractive effort isn't 41,895! Guess I ought to get one of those clunkers... to pull me out when I get it stuck! :P

You'll notice that it also will pull only about 85% of it's weight. (tractive effort) I think that's about the maximum for any tractor on dirt. Please don't confuse this with pulling 10 times it's weight on sleds or wheels. This is a horizontal force.

Share this post


Link to post
Share on other sites

At the tire speed run for the smaller tires they grow to almost the same dia. as the bigger tires. Effective gear ratio isn't where the benfit of going to a smaller tire is. Wish I could explane that exactly. Best I can offer is the pushing against the mass of sand as it fills the paddles, not pushing against the friction sand offers at rest.

Share this post


Link to post
Share on other sites
I didn't say you couldn't have weight shift in a Quad since you can have a weight shift/transfer in ANY tractor. I was just saying that it didn't seem to be any advantage to take weight off one set of drivers and add them to another set. Nobody has been able to explain how that would help.

No, I don't want to pull against any "almost  9380" that weighs 12,000 lb more. That was one of my unfair advantages, remember? Even then the 38,000 lb tractive effort isn't 41,895! Guess I ought to get one of those clunkers... to pull me out when I get it stuck!  :P

You'll notice that it also will pull only about 85% of it's weight. (tractive effort) I think that's about the maximum for any tractor on dirt.  Please don't confuse this with pulling 10 times it's weight on sleds or wheels. This is a horizontal force.

38,000 lb wasn't max pull, it was max pull in 3rd gear, he's got two more holes to go!!! The advantage isn't in taking weight off one set of drivers, the advantage is in transferring the weight to get an approximate 50-50 balance. That's why they start out at 60-40 or so. Then everything pulls goooddddddd!! Just watch the rear tires hunker down sometime on a 2WD tractor pulling any large implement to see the effects, or any 4WD for that matter, but it's probably easier to see the tires squat on the 2 WD as it does it's thing. BTW that tractor would normally be pulling two 17 yd pans around here!! Actually, they are doing it with 325's!

Chads

Share this post


Link to post
Share on other sites

Shifting to a lower gear doesn't necessarily give you more tractive effort, just makes it spin. Remember dirt isn't concrete. Since he has more horsepower he will be able to spin his tracks in a higher gear than I can but down shifting won't necessicarily "get it done".

Loren, I don't want to comment on the sand throwing thing, thanks. I'm not doing this in sand because that's the great equalizer. I have no idea how a TD24 does in sand.

Share this post


Link to post
Share on other sites
Shifting to a lower gear doesn't necessarily give you more tractive effort, just makes it spin. Remember dirt isn't concrete. Since he has more horsepower he will be able to spin his tracks in a higher gear than I can but  down shifting won't necessicarily "get it done".

Loren, I don't want to comment on the sand throwing thing, thanks.  I'm not doing this in sand because that's the great equalizer. I have no idea how a TD24 does in sand.

When looking at the numbers they go up steadily as the gears go down, it's no different than your TD24. Put your 24 in 3rd(5.0 MPH or so) and put the quad in a 5.0 MPH gear and see what happens. BTW, I'd expect the quad to be better in tractive efficiency than a standard wheeled tractor.

Chads

Share this post


Link to post
Share on other sites
Shifting to a lower gear doesn't necessarily give you more tractive effort, just makes it spin. Remember dirt isn't concrete. Since he has more horsepower he will be able to spin his tracks in a higher gear than I can but  down shifting won't necessicarily "get it done".

Loren, I don't want to comment on the sand throwing thing, thanks.  I'm not doing this in sand because that's the great equalizer. I have no idea how a TD24 does in sand.

Perhaps you could tell us this "tractive effort" formula you're using. I would like to see how you keep coming up with this as you saving grace.

Thanks.

Share this post


Link to post
Share on other sites

"When looking at the numbers they go up steadily as the gears go down,"

This is only true up to a point. If you had 2500 HP and 15 gears you couldn't keep downshifting and getting more tractive effort. There is a maximum here for dirt and it has to do with WEIGHT, surface area of wheels or tracks, and shape of wheels or tracks. Too much power or too low of gearing will not get it done, will just spin out. Once he starts spinning I'll take off pulling him backwards. No weight shift required. :rolleyes:

post-275-1124252267.jpeg

Share this post


Link to post
Share on other sites

As I said before this 85% of weight is gleaned from specifications I've seen going thru Nebraska test reports and ads for tractors. They vary some naturally but I've never seen one advertised that can equal it's own weight on dirt and we don't do much tractoring on anything else. Normal 2WD tractors won't do that good unless conditions are ideal and THEY need a weight transfer to get that good of numbers.

I would be interested in seeing any data to the contrary. :wacko:

Share this post


Link to post
Share on other sites

×
×
  • Create New...