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What do you do with your Quadratrack?

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"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:

So where are your numbers for the surface area on the quad and the 24? What track sizes are we dealing with here and why would your 24 have the ability to gear lower and still maintain traction and not the quad?

Are you absolutly sure there is no way to "amplify" the tractive effort with modern chassis design? What are the soil specs that we're going to pull on? Why cant the rubber tracks compress the soil for grip with their lug design?

Just curious. Thanks.

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R-Cubed

  You,Me, The Frankencat,My snowmobile,

at the old airport Midnight. :D  :D  :D  :D

Geronimo!!!! :D:D

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i found a type of tractor bluebook that lists the value of different tractor models. they also show some specs.

the 9380 quads shipping weight is 32500.

front mounted weight option counts for 30 weights.

twenty rear weights.

5000 pounds worth of weights, 1800 pounds of fuel = 39,300 gross weight.

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pokey,

the only way to gain effort for the quad would be to somehow positively lock the track to the ground so it cannot slip. a super widetrack with 10" spikes might do the trick. if you can ensure the tracks will never slip, tractive effort due to machine mass is irrelevant and horsepower applies.

the quads drawbar is mounted higher than the 24's, these things will hit you just below the knee. but i do not believe there is enough difference here to win in a pull.

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wow this is a great thread. my money is on R-Cubed's TD24, just like the tractor pulls when the vintage tractor out pulls the new higher HP one, and then a 8-12HP steam tractor pulls it to the end! TORQUE + TORQUE + TORQUE!

Jake.

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Well, I finally got a fan! Thanks Aussie.

"If the Quad could somehow lock his his tracks to the ground ..." That's the real point, isn't it? Maybe if it had 2" growsers? I'm reminded of the old addage, "If I had some ham I could make a ham sandwich ...if I had some bread". IF is the biggest word in the English language.

32,500 + 5000# ballast? I don't need any ballast but since my seat is 5 feet wide I will take a few fat friends as wittnesses and to shift weight. Not much of a threat, IMHO.

B)

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Well, I finally got a fan! Thanks Aussie.

"If the Quad could somehow lock his his tracks to the ground ..." That's the real point, isn't it? Maybe if it had 2" growsers? I'm reminded of the old addage, "If I had some ham I could make a ham sandwich ...if I had some bread". IF is the biggest word in the English language.

32,500 + 5000# ballast? I don't need any ballast but since my seat is 5 feet wide I will take a few fat  friends as wittnesses and to shift weight.  Not much of a threat, IMHO.

B)

Why are you so sure that the quad cant "lock his tracks to the ground"?? Are you demanding that the quad grind off all his lugs to make this pull? What is it about the rubber tracks that makes them so unable to hook up to the ground in your mind??

I'd still like to know what formula you're using to find the tractive effort of the 24. If you're using the ones for the rail road locomotives, you probly better study them a bit more.

Also for the pulloff, are we going to limit the machines to the same gear ratios or track speed for a fair comparison?? I also need to know what size tracks you're going to let me use on the quad, and what lug pattern. The quad has several different tracks it can use.

And one other question just for my own info, it sounds like you believe "tractive effort" is the only factor needed for finding the conclusion here on paper, is this true??

Thanks.

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I haven't gotten into this yet but, I just want to make one point. If you gear down the quad, it's bound to slip the tracks, unless it starts to move the 24 first. It's no different then our semi. If you are going to slow with to heavy of a load and you start to get stuck your done. Speed torque and traction are all directly related.

As to who would win the pull off, I don't know.

Ryan

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Speed torque and traction are all directly related. 

Yes. Well stated. :D

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"Lock your tracks to the ground"? How is this possible? and to do so what do you need, cleats that don't SLIP no matter what? Tractor engineers have been in search of such designs for 100 years. The dirt will slip even if the cleats don't.

As for where I'm getting my 41,895# of tractive effort, that comes out of my manual on page 4 of the spec sheet which is given for all gears and all speeds for a stock engine. It also shows 6200 lb at 8.0 MPH in 8th gear. It has comments as follows:

"the above observed pulls were obtained with the engine operating at the governed RPM.When pulled down by overload, the crawler tractor engines develop greator torque or turning effort than at the rated RPM and at reduced speeds. This results in the increased calculated draw pulls."

I wouldn't be surprized if I could exceed that with my souped up engine. OOPS! I said that horsepower is superfluous. I get that in low gear but he can use any gear he wants.

As Aussie said I wouldn't want to take on one of those old 12 HP steam tractors with 20 foot dia wheels and weight like a Tiger tank.

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Wow - you guys are still going at it! Interesting post!!!!!!!!!!

My $.02 - on a straight pull with a cable - where no "loading" of either machine can take place - I'd give it to the TD24 as long as it had good grousers and a good level packed gravel type surface. Mud or anything else I'd have to go with the quad. Bulldozer's weight/traction/gearing is king on a level non loading pull.

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Wow - you guys are still going at it! Interesting post!!!!!!!!!!

My $.02 - on a straight pull with a cable - where no "loading" of either machine can take place - I'd give it to the TD24 as long as it had good grousers and a good level packed gravel type surface. Mud or anything else I'd have to go with the quad. Bulldozer's weight/traction/gearing is king on a level non loading pull.

You're getting closer. (i think) But still it would be fun and interesting knowledge to find out how you came up with that idea about the quad doing better in other "tractive" conditions and surfaces. If "weight/traction/gearing" is king on the crawler, why would you give the title to the quad in the other arenas?

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"Lock your tracks to the ground"

That's your quote, not mine. :D

What details if any did your manual give for the surface the crawler was on when these ratings were taken?

Let me ask this one more time. How can you determine "tractive force" without factoring in the adhesion capabilities of the tracks on a given surface? There are so many variables in just the adhesion factor. I'm not going anywhere near horsepower, just the tracks ability to hold the soil and develope the force that can be measured. In a straight line pull too.

If you look at this site again, http://www.abe.iastate.edu/AST335/2003/Tra..._WismerLuth.pdf look down on page 9. Maximum drawbar pull is developed at 100% slip. This means that if you are still making foward progress, you still have pull to spare. Right?? Now, if you start to slip, you are compacting the soil beneath the tracks, right?. As the soil becomes compacted, it becomes harder, am I correct? The rubber tracks with an angled rubber cleat have more surface area per foot of track than the steel 2" grouser pad, in contact with the hardened soil. Can you tell me where I am wrong here? If I am wrong, I'd like to be corrected so I can learn new things.

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Old Pokey, I've been thinking about that. How wide and long are each track on the quad? I would have thought that the 24 would have more surface contact then a quad. I'm not saying that. That is just what I thought.

Ryan

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R, nowhere in my post did I refer to doing this pulloff in sand. In fact, the last sentance I specifically suggested that there may be a unknown phenomon that would change the predicted outcome of this pull. The same situation also shows itself in tractor pulls, antique tractors vs. the blown V8 jobbers. The antiques do good with the "less slip" method, the blowers adhere to the "just git 'er DONE!" theory. Just another aspect of pulling to think about.

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Oh and hey R, I'm also a fan of your monster. But, I'm also a fan of what would be one heck of a competition! :D

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Old Pokey, I've been thinking about that. How wide and long are each track on the quad? I would have thought that the 24 would have more surface contact then a quad. I'm not saying that. That is just what I thought.

Ryan

Ryan, that's a good question. I dont know for sure, I guess I could look it up. But I'm thinking the tracks themselves and their shape and composition is what will determine their adhesion capability.

Lets say the quad and the 24 were equal in track frame displacement just for the sake of arguement. If the quad was to pull the 24 backwards with its rubber tracks, what do you suppose would happen if the 24 had rubber and the quad had steel?? I believe this is where the quads chassis design comes into play with its tractive effort. Contrary to popular belief, or seems to be popular belief, there is allways weight transfer happening when power is applied. Even in a straight hooked pull. The 24 has only 2 rigid lengthwise track frames that pivot on its rear drive sprocket. The quad has 4 track frames that pivot in the middle of each one. The high drive sprocket on the quad together with the walking track frame, I believe but cant prove it.....yet, is part of what gives the quad an advantage even in a straight hitched pull.

I have a few emails out to a few engineer freinds of mine, but dont expect a speedy reply.

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That site is just adding more fuel to the confusion. 100% slip = max drawbar pull?? 100% slip means you are not moving does it not? How could that be a winner in a pulloff?

My 24 has 43 square feet of track surface on the ground and another 14 square ft of growser area. If you can find that information on the quad that might help in our paper pulloff. I have 4" wider than standard pads and optional longer wheelbase.

As for the statics and dynamics of traction in dirt, I'm not a PHD in dirtology, sufice it to say we will both be in the same dry dirt so that shouldn't be a factor. :wacko:

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You guys are leaving off the best part. Weight is one thing, traction is another. Steel grousers can always be taller and thinner than rubber. Deeper penetration is what it is all about, because lateral breakout force goes up in a non linear fashion as depth increases.

MD

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R Cubed,

you are wrong! that site is not adding more confusion. that site is what switched me to your side.

it works both ways, if your machine will pull 41,895 pounds at the drawbar, it will take 41,896 (notice the 6) pounds worth of effort to move your machine with the tracks locked into place. if i am thinking correctly, it will not matter that much if your tractor is running or not! if the tracks are locked up, it will take in excess of 41,895 pounds to drag your tractor.

velocity, gearing, HP, torque none of this matters when you are hooked together starting from a dead start. traction is the only item you can factor in here. i do not see the quad as having enough of an advantage in the traction area when you deduct 15% from 39,300 pounds of operating weight of the quad.

now if you used about 100 feet of cable and started the two tractors back to back, velocity would be a factor here.

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This is a better post than the King's boat discussion:lol:----sorry I was so late in picking it up.

SawMill has called it----gotta meet up for the old shoot out. Hitch 'em together and let the truth be told. I'm pretty good on cooking ribs----SawMill if you could bring along a little wood to cook with, we can probably get the King to bring down some ice (don't reckon we ought to trust him with the beer) :rolleyes:---and we will have the great pull--off!!

Lots of interesting thinking going back and forth here----great to see all of the comments and everybody is still having fun.

I did calculate the drawbar pull required to pull a Dondi ditcher forward back in the late 70's by pulling against a hydraulic cylinder and taking a reading on the pressure gauge----calculated the area of the piston and multiplied times the pressure to give me an estimate on the pounds of drawbar pull required. This same principle could be used for the TD-24 and the Quad tractor to answer our question without these old boys having to haul their tractors across country to a convenient location for all of us to witness. Be best if the same cylinder, pressure gauge and hitch arrangement was used---would eliminate any variables. Using the same hydraulic cylinder---all we would need to know was who pulled how much pressure against the pressure gauge (presuming that there is a large enough tree in the vicinity of each of these tractors to offer adequate pulling resistance) ;) ---SawMill we might have to depend on you to check the trees out and sorta be our official judge (sure wouldn't want somebody to pull a tree down and get hurt).

Delta Dirt

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Seems like all you have to do around here to gain notoriety is make an idle boast that you can beat someone in a tug-o-war. Was probably a worthwhile exercise since it got us thinking logically about pulling tough loads.

U-joint, I didn't get much out of that traction site since it appeared to be for two wheeled klunkers that needed weight transfer. But if it shifted you to my column then I better take another look.

Yes, I believe my long thin growsers give me an unfair advantage but am surprised that someone just now picked up on that. Sawmill stated long ago that if I locked my tracks he wouldn't be able to pull me. (Wish I had brakes that worked)

Pulling against a hyd cylinder and measuring the pressure in the oil is BRILLIANT! Wish I had thought of that. There would always be doubts though about the different type soil being used, moisture content, etc.

Now have 4 or 5 believers and counting! :rolleyes:

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Seems like all you have to do around here to gain notoriety is make an idle boast  that you can beat someone in a tug-o-war.  Was probably a worthwhile exercise since it got us thinking logically about pulling tough loads.

U-joint, I didn't get much out of that traction site since it appeared to be for two wheeled klunkers that needed weight transfer. But if it shifted you to my column then I better take another look.

Yes, I believe my long thin growsers give me an unfair advantage but am surprised that someone just now picked up on that. Sawmill stated long ago that if I locked my tracks he wouldn't be able to pull me. (Wish I had brakes that worked)

Pulling against a hyd cylinder and measuring the pressure in the oil is BRILLIANT! Wish I had thought of that. There would always be doubts though about the different type soil being used, moisture content, etc.

Now have 4 or 5 believers and counting!  :rolleyes:

I dont know why you think your grousers give you an "unfair" advantage. They are part of what makes your 24 the machine that it is. I think its fair.

Yes, there will allways be doubts about the pull untill it actually happens.

I'm certainly not trying for "notoriety", but if it gives you some, thats great.

Could you please just tell me what conditions you need to for the dirt so you could win this thing? And then admitt that it is the conditions of the dirt that were what allowed the win. In other words, if the 24 will out pull the quad in dirt conditioned so the grousers can penetrate, but the quad will out pull the crawler on compacted hard dirt where the grousers cant get a grip, then the 24 is only the pull king in dirt conditioned just right, not the pull king period.

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