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Post by Woodbeef on Nov 29, 2003 20:16:38 GMT 1
Yup pretty well clear as mud!!!!
So now let's get back to this one wheel locked up,and going straight thing.......
Also the turning with diff locked part......
I'm waiting!!!!!
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Post by eppie on Nov 29, 2003 20:18:36 GMT 1
Well i'm back there.. So what is it, that you disagree with?
By the way, the strains on the diff is a different subject.
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Post by Woodbeef on Nov 29, 2003 20:22:07 GMT 1
The locked up wheel's effect on the forward direction of the tractor.........
The extra speed is only applied while turning around the axis of the locked wheel......not actual forward motion.....
Yes the strain on the driveline is part of this discussion...you brought the turning with a mfd part into it........
So I'm still waiting........
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Post by eppie on Nov 29, 2003 20:32:59 GMT 1
Yes i brought turning with a diff lock on an mfd.. But you brought in turning with the diff lock itself.... quote: "Just like try turning with your diff locked....... "
The locked up wheel's effect on the direction of the tractor...
It does apply side force to the tractor, because of its eccentric point of force, but that force is equalled by the side force the rolling wheel can handle.
The extra speed is applied also when you're not making a turn, and the other wheel is blocked. A diff is not speed dependent in it's ratios.
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Post by Woodbeef on Nov 29, 2003 20:37:56 GMT 1
Now are you quoting actual things that have happened?? Or are you talking only theory from your books again??? Ok so why not just answer the amount of driveline strain questions then? ![???](//storage.proboards.com/forum/images/smiley/huh.png) ?
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Post by eppie on Nov 29, 2003 20:48:03 GMT 1
from the books vs. things that actually happen:
I have driven in a straight line wih one blocked wheel. that's an actual event. If you dont believe me, then just say so. The rest is a theoretical explanation of the forces that apply.
Every event has a cause.
Off topic:
Turning with the diff lock on: when you do so, one wheel will have a slower circumferential speed than the forward speed. (negative slip, like when you're braking) The other will have a smaller circumferential speed than the forward speed, (positive slip, ordinary spinning wheels.)
In this case, the wheels just slip. So the strains on the driveline will not be bigger than in any other case of wheel spin, in a situation with the same axle loads and field conditions.
I agree that, maybe, a diff lock isn't designed to take forces that big, but for the driveline itself it's nothing different from the situation where you have your tractor hooked up to a very big tree and the wheels just spin.
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Post by Woodbeef on Nov 29, 2003 21:03:24 GMT 1
Ok now lets seperate the facts from the fiction here....Just talk real world happenings....not book could happen under perfect conditions....
so if you traveled straight ahead at twice the speed with one brake locked.........your brakes need some work then....or you did not travel straight ahead with out any steering correction for very far.
As for your locked differential explanation....you might want to rethink it.......you explained an open diff(unlocked) not a closed(locked) diff. Once a diff is locked up the differentiation capabilities are no longer there....hence one wheel will no longer spin like crazy and the other sits still....unless you hear a whole heap of clicking,chattering and grinding noises coming from the rear end!!!
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Post by eppie on Nov 29, 2003 21:07:36 GMT 1
O.k. i will add to this: the forces on the driveline wil be no bigger than in the situation when the diff is locked , tractor hooked up to a giant tree, and the wheels just spin without moving the tractor forward.
that's what you wanted to hear ?
By the way i said wheelSSSSS, not just one wheel.
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Post by Woodbeef on Nov 29, 2003 21:22:44 GMT 1
I still think you are missing out on how a differential actually differentiates the power that is driven through it.......
Both wheels spinning at the same speed while the diff is locked is not the same as turning with the diff locked.....
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Post by JD Kid on Nov 30, 2003 8:17:29 GMT 1
Hi ya's well well guess what i have in the 8350 that i just recalled today ?? a speedo off the gear box and 1 off a wheel ,yep ya read it right 2 speedos ..now if ya's keen and think a gearbox speedo is close eneff for the test ..will we try a non braked turn, a braked turn and a brake and try and keep it in line test !! the rev will be 1800 hand set with no load on a flatish field speed 6 kph and tested both 2wd and fwa.. so who want's the test to happen??? i'll do it some time this week ...so place ya bet's what will happen ,will the valtra go 2 times as fast in a line ?? the loser must with in 2 weeks post a pic on here dressed in drag ...ya will know where to place ya bets after 24 hours to think it over ![;)](//storage.proboards.com/forum/images/smiley/wink.png) catch ya JD Kid
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Post by eppie on Nov 30, 2003 13:40:05 GMT 1
Why not, Woodbeef ? In both cases, the diff is locked and the wheels are spinning. Please explain why you think this is different ? JD kid, I was talking about a wet, muddy street, not a field where the lugs penetrate the ground. I dont know if the same thing applies for your Valtra as for our Deutz. Totally different tractors. I will not bet that the tractor speeds up two times, it has not enough power so it will die down in revs. In my situation, i think i drove about 15 km/h. It's o.k. for you to try that, but i dont bet on it. If you dont believe me, why should i believe you ![???](//storage.proboards.com/forum/images/smiley/huh.png)
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Post by New Hollander on Nov 30, 2003 15:20:18 GMT 1
I'm still not getting the point of this discussion but I think I have to back up Renze at this point. Here's a practical view of Renze's point: When I am mowing in the morning while the grass is still wet with a heavy 3 point mowerconditioner and make a left turn, the left rear wheel is lifted a bit and starts spinning. There is almost no weight on it. When I apply the left brake, the tractor starts driving again, even in a straight line. When I keep pressing down the left brake pedal, it is even possible to drive faster than the normal speed because on the left wheel the speed is zero and on the right wheel it is doubled because of the differential. Ergo, when you're mowing on a wet field, use fwd or else you will ruin the grass.
New Hollander
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Post by Richard_S on Nov 30, 2003 17:42:19 GMT 1
I don't follow this properly, but I agree with Woodbeef about turning with the diff locked on hard ground, this will strain the lock more than pulling straight where the lock just had to keep the wheels rotating at the same speed - in this situation thay are not fighting each other. Renze is correct that if one wheel is stopped, the other wheel will rotate at twice normal speed. This happens for example when you drive into a heap with a 2wd loader tractor, when forward travel stops, the driven wheel spins at twice normal speed. I cannot see how Renze manages to get this to happen when actually moving though, because if one wheel is stopped, this will slow the tractor down before the other wheel can speed it up Or maybe the tractor turns sharply to one side and overturns, landing on Renze's beloved Volvo ;D
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Post by JD Kid on Nov 30, 2003 19:52:30 GMT 1
OK guys i got the good oil ..the 2 times thing toss so far out the window that ya arm gets sore .. now NH ya saying one wheel is off the ground and untill ya put ya foot on the brake ya done move ,with have a open diff the same will happen on ice in a open center diff in a car thats what LSD (not the drug but the diff head is for)..yep the muddy road welli can get pudd's to back me on this ground it's that tight that ly lugs are twisting to get grip a few mm of rain and the only thing ya can drive is a ATV a ute or tractor even a dozer ya stay off till it drys (yep ya don't feed out in the winter here cos ya can't go any where )what renze has been talking about might HAPPEN but it would take a few factors 1 the inside or braked wheel must skid it can not have any grip what so ever 2 ya have to have a large weight behind ya pushing ,the speed ya incress by will be determend by this weight ..i have seen it happen before but it is not driven ie go down a steep hill with a load and tap the brake to turn ya will speed up try the same thing going up hill and ya will stay the same ,the only time it happens is if the non braked wheel can over run the input speed ie free wheel .. richard.s the silage one is a good point ya also note ya motor picked up rpm while this happened??say ya has a big grap of silage on the loader while this happened and ya could dump it what would happen?? catch ya JD Kid
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Post by Woodbeef on Nov 30, 2003 22:21:00 GMT 1
Hey Richard and NH,
Thanks for weighing in on this discussion......I was getting dizzy from running around in circles!!!!
One thing though on you factual story NH.....you had an extra weight hanging off of one side of the tractor. So this does skew the data a bit......
As for Doc.......think once again about what you have just posted above one more time.......turning is different from both wheels spinning in a straight line with both examples having the diff locked........No theory now on this just real world facts ok,Doc.......
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