poor mans locker.

without difflocks i often get hooked up on the odd rock or whatnot on hills. its become a common practice for me to slip my left foot over the brake pedal and jab it a few times.
It seems to work occassionally, am i right or is it just the vehicle finally gaining traction?? ???

[RobertM]

I have had a few times that that has helped a bit and it has been mentioned a few times in the mag I am pretty sure.

[turbo80]

I’m to believe that with out diff locks or LSD in your vehicle :'( that all the power is diverted to the free spinning wheel when bog or hung up to try and counter act this you can slightly transfer the power by applying the brake pedal locking up the free spinning wheel transfering the power to the bog wheel ;D. This has work for me a few times 8) but they way I could afford Lockers was instead of buying the misses flowers I save up and get some lockers ;D and made up for it later ;). You will never turn back besides it was a lot quieter :-X around the house.

You will never turn back besides it was a lot quieter :-X around the house.

so THATS how ya do it!!!! *runs for the credit card* ;D
http://www.vistawebdesigns.com/smile.gif

ive seen the handbrake(vehicle mounted one) used on a ramp in the mag and described as poor man locker but i have a tendency to use the foot brake. my question is apart from the obvious of going an spending the money. should i be using the foot brake or just the handbrake??

[PaulB]

Yes you are right! Using the brakes in the fashion that you describe is similar to TRACTION CONTROL.

The McLaren F1 team got in trouble for doing this after electronic traction control got banned. They only got in trouble because a nosy photographer (Darren Heath) photographed the cockpit showing the extra brake peddle which actuated the rear brakes to a specified pressure.

If you have an open diff and lose traction on one wheel then apply the brakes lightly it basically makes the spinning wheel think that it has gained traction again. Therefore torque is transfered back to the other wheel which has grip resulting in forward motion.

Series II Landrover Discovery's have an electronic version of this where the computer applies the brakes for you. It's called TRACTION CONTROL. The Landy is only more sophisticated in that it can brake individual wheels thanks to it's four channel ABS.

HOWEVER, just like the Disco TRACONTROL you need to plant the right foot while using the left on the brake pedal in order to gain the most benefit. It should be noted that this system doesn't work well on soft sand. For this you need a difflock which is why I am looking for a series II that still has the difflock actuator sprocket on the transfer case. In typical LR style they didn't remove the locker, just the switch in order to save money!

Using the hand brake will work to a degree but only on the one (usually rear) axle. It will also cause premature wear of the brake shoes/pads as they are not designed for this purpose.

I reckon anyone who can master this type of poor mans traction control is anything but a poor driver.

I have seen a few short videos i found on kazaa from the states mostly with jeeps and zooks in mud or on a slippery hill, and they could have used this advice! the vehicles stopped half way and there was only one wheel spinning out of four! usually the front inside wheel. Either these guys forgot to engage 4WD, or they don't have LSDs

seems very odd that only the front inside wheel is spinning dao. sounds like rear diffs are stuffed or no tail shaft installed??

[PaulB]

A permanent 4WD with no centre difflock only requires one wheel to lose traction to bring things to a halt.

A permanent 4WD with no centre difflock only requires one wheel to lose traction to bring things to a halt.

a zook with permanent 4wd???? they onlt just worked out how to manufacture air con.

seems very odd that only the front inside wheel is spinning dao. sounds like rear diffs are stuffed or no tail shaft installed??


I would upload the video to my web server but i am running out of space and it's 12 meg in size.....

[BushBoy]

Trouble is with jabbing the brake, it would also slow the truck down or loose revs would it not?
s'pose it's better than nothing eh?]

cheers

[baby_troupe]

I don't jab the brake.
I apply gently increasing pressure until I get a little drive from the wheel on the ground.
It seems to work most of the time for me. If that fails, I will either try a different line or get out the recovery gear.

im gunna have to invest in at least a lockrite as soon as i get back in a month or so, cause ive just replaced all my brakes an i dont wanna wear the new set out quikly.
thanks for the advice

[Rotor1]

So if your budget will stretch to only one locker,say an ARB, which would be the best axel to choose? In my case on my VX80 diesel [full time 4wd] it has LSD on the back so I guess an ARB on the front would make sense?
I also have a 74 FJ40 4 speed [part time 4wd] and are wondering which would be best on this, the front sounds good as all the weight is there and you can move the wheels side to side if your really stuck?
Thanks
Rotor

[baby_troupe]

Front.
I have posted my reasons in the thread you have started on this question.

;D ill tell you the definition of a poormans locker !@!!
weld up the spiders !!!! constant and all 4 wheels spin till the welds break!!
lol1

[crazyjon]

Brakes are a surprisingly good form of tractin control. Before I upgraded to the 4b I used to use the handbrake a lot in the commodore. Mostly on slipery boat ramps and the odd dirt trail that was a little sus in 2WD. I used to apply throttle until the wheels were spinning then ease on the brake adding pressure until i got drive, then hold my breath till i'm away and release the brake. Got me off a number of ramps when all anyone esle could do was wheelspin!

Cheers.

[akdoc]

You just invented traction control mate. This is how (TC)traction control works by applying the brakes to the slipping wheel ;). Driving using brakes to lock wheels also wears out brake pads. This is why many people are against TC, going bush with traction control can get you over ground the vehicle would not normaly manage. However if the brakes fail you will never get back. TC like lockers can also cause roll overs in unexperienced hands as even with only two wheels on the ground you can still drive forwards.

I actually put the "poor mans locker" into action today... and it worked like a treat!!! hehe

[Fieldsy]

just a point don't try useing the park brake on an old cruiser or some of the rovers ( I think)cause the park brake is on the transfer case. = wont do bugger all. but yep it's worth wile thing to try if ur geting stuck

[etho]

I actually put the "poor mans locker" into action today... and it worked like a treat!!! hehe

it does, though not as well in the wet (obviously!) although i guess it would depend on how quickly ones brakes dried out!

[oiler]

Mine is an 80 series standard and I've been using this method of traction control for a couple of years and don't seem to have any adverse effects. My handbrake wouldn't actually stop the vehicle and is good for getting traction back on a rear wheel however if I need it at the front as well I use the foot brake. Not a problem on the 80 as the brakes are huge and typically I get about 80000-10000K out of a set of front pads. I have heard you get a lot less on a auto GXL. I wouldn't be concerned about wearing out your brakes doing this maneuver.

My poor mans locker broke a cv lately ;D

[dogbreath_48]

im gunna have to invest in at least a lockrite as soon as i get back in a month or so, cause ive just replaced all my brakes an i dont wanna wear the new set out quikly.
thanks for the advice


When you think about it, slowing a 2 tonne 4wd from 100km/h is probably gonna do more damage to brakes than applying them for a second or two when the wheels are turning at maybe 40km/h. I don't think wearing out pads or discs would be a problem. The only problem i could see would be overheating an auto (if you go overboard) and maybe (very slightly) increasing wear on the drivetrain (Uni's, transfer/g'box etc).

I never considered using the brakes for TC, but it makes so much sence. I'll have to give it a shot some time!

-Stu :)

[p38arover]

just a point don't try useing the park brake on an old cruiser or some of the rovers ( I think)cause the park brake is on the transfer case. = wont do bugger all. but yep it's worth wile thing to try if ur geting stuck


All real Land Rovers/Range Rovers (even the Freelander, dunno about the new L322 RR) use a transmission brake so, as you say, pulling the handbrake won't work

Ron

[FJ60]

putiing the brake on is like traction control(sort of) you cant relly call it a locker but im glad u r investing in one H@M

[Humpy]

Having tried this a few times to test the theory, I think this poor mans locker is an urban myth.

Theory says that friction coefficient reduces when an object is moving, as opposed to stationary.
Experiment to prove theory (http://physics.clarku.edu/courses/110labs/Lab4.pdf)

Assuming your brakes are working properly and applying equal force to each pair of wheels. If you have lifted a wheel and it is spinning the braking force will be slightly less on it than on the one that still has traction and is not moving.

An open diff will direct torque equally to each wheel, so applying the brakes is actually counterproductive, as you are giving the wheel with traction more work to do.

Even if this theory is wrong and friction is constant, the best you can hope for, is effectively a reduction in throttle which may help the tyres grip and get you up, out or over

Traction control only applies braking force to the spinning wheel, making the wheel with traction drive that much harder.

Transmission handbrakes will not work for traction control and wont work as a handbrake if you have two wheels of the ground unless you have a difflock

A poor mans locker is a welded diff or a stolen locker, both of which are illegal but very effective.

Having tried this a few times to test the theory, I think this poor mans locker is an urban myth.

Theory says that friction coefficient reduces when an object is moving, as opposed to stationary.
Experiment to prove theory (http://physics.clarku.edu/courses/110labs/Lab4.pdf)

Assuming your brakes are working properly and applying equal force to each pair of wheels. If you have lifted a wheel and it is spinning the braking force will be slightly less on it than on the one that still has traction and is not moving.

An open diff will direct torque equally to each wheel, so applying the brakes is actually counterproductive, as you are giving the wheel with traction more work to do.

Even if this theory is wrong and friction is constant, the best you can hope for, is effectively a reduction in throttle which may help the tyres grip and get you up, out or over

Traction control only applies braking force to the spinning wheel, making the wheel with traction drive that much harder.

Transmission handbrakes will not work for traction control and wont work as a handbrake if you have two wheels of the ground unless you have a difflock

A poor mans locker is a welded diff or a stolen locker, both of which are illegal but very effective.


well mate.... i tried it too..... and it worked rather well..... not in bad terrain, but i was trying to get a few flex photos a while back and drove into a contour ditch at an angle...... when i was part way through, the car stopped and the opposing wheels were spinning.... which is no mean feat considering i have a pretty good LSD in it..... anyway, i sat there and applied the brake a little and the car proceeded to move through the ditch..... i tried it again 2 more times, did the exact same thing each time.... you can prove anything in theory... practice is a different thing. If you have an open centred diff, and one wheel it spinning, and you apply the brake gently, it will apply equal force to both wheels...... the diff would then, as you say, apply torque equally....... then the one wheel not turning would then have to turn would it not? considering that you have the other wheel spinning with the same amount of brake applied.

[Humpy]

well mate.... i tried it too..... and it worked rather well..... not in bad terrain, but i was trying to get a few flex photos a while back and drove into a contour ditch at an angle...... when i was part way through, the car stopped and the opposing wheels were spinning.... which is no mean feat considering i have a pretty good LSD in it..... anyway, i sat there and applied the brake a little and the car proceeded to move through the ditch..... i tried it again 2 more times, did the exact same thing each time.... you can prove anything in theory... practice is a different thing. If you have an open centred diff, and one wheel it spinning, and you apply the brake gently, it will apply equal force to both wheels...... the diff would then, as you say, apply torque equally....... then the one wheel not turning would then have to turn would it not? considering that you have the other wheel spinning with the same amount of brake applied.


Your right Roe, theory is only good if it can be backed up in practice. I tried and it didn’t help me. Then I tried to work out why it didn’t work and I came up with my last post.

When both wheels are braked, the pads apply an even force to each disk, (or drum) this then creates a friction force on the disks when they are moving or attempt to move. This force is approximately equal and slightly greater on the one that isn’t moving.

The driving force is also equal on each wheel, if one wheel cannot transmit all the torque from the engine to the ground it will lose traction and spin. The wheel with traction will be allocated the same torque by the open diff. Unless more load can be added to the spinning wheel, by braking it or regaining traction. Or less driving force becomes required for the stationary wheel, it will not turn. Adding equal braking force (torque) to both wheels will not help.

A difflock will not provide equal torque to each wheel, unless in a straight line on equal traction surfaces. Difflocks provide equal RPM, sometimes one wheel will have all the torque and one will have nothing.

A difflock will not provide equal torque to each wheel, unless in a straight line on equal traction surfaces. Difflocks provide equal RPM, sometimes one wheel will have all the torque and one will have nothing.

on equal traction surfaces? is that not the whole idea of a diff lock? my understanding is that the only time the diff lock will release is when one wheel is trying to turn faster than the other as it does when cornering. If you need equal traction, then i would say we are wasting our money buying them ???

[Humpy]

on equal traction surfaces? is that not the whole idea of a diff lock? my understanding is that the only time the diff lock will release is when one wheel is trying to turn faster than the other as it does when cornering. If you need equal traction, then i would say we are wasting our money buying them ???


You dont want equal torque, you want maximum torque to whichever wheel can use it.

If you have one wheel off the ground it cant do any thing usefull, so whats the point of giving it any torque, or driving force.

Ideally you would be able to direct torque to the wheels in proportion to the traction they had, and not be related to the speed of the wheel. so when you drive over bumps or around corners the drive stays at the maximum required.

No one has truly got it right yet, the closest I know of is Sam Overton's traction control.

I'm missing your point...... what difference does it make if you have lifted a wheel?? isn't that the reason you put a locker in in the first place? so when you lift a wheel, you still get traction regardless of who, what or where you want/need torque.....

Humpy, you are full of it.

[Humpy]

My point is that if you loose traction on one wheel, it cant provide any drive, an open diff will then give the same torque/drive to the other wheel, so for that axle, 0 drive + 0 drive = 0 drive and 2 driving force in engine

If you add an equal braking force to each wheel, 1 drive + 1 braking + 1drive + 1braking = 0 drive

If you brake only the spinning wheel you get, 1 drive + 1 braking + 1 drive + 0 braking = 1 drive.

The ideal diff would have 0 drive + 0 braking + 1 drive + 0 braking = 1 drive, with 1 driving force left in the engine

Spinning wheel is the first drive/braking and the engine has power for 2 times the driving force

Edit: Fixed some stuff I hadnt checked in my rush to post before the site crashed again

[Humpy]

Humpy, you are full of it.

Full of knowledge and intellect ;D

My point is that if you loose traction on one wheel, it cant provide any drive, an open diff will then give the same torque/drive to the other wheel, so for that axle, 0 drive + 0 drive = 0 drive and 2 driving force in engine

If you add an equal braking force to each wheel, 1 drive + 1 braking + 1drive + 1braking = 0 drive

If you brake only the spinning wheel you get, 1 drive + 1 braking + 1 drive + 0 braking = 1 drive.

The ideal diff would have 0 drive + 0 braking + 1 drive + 0 braking = 1 drive, with 1 driving force left in the engine

Spinning wheel is the first drive/braking and the engine has power for 2 times the driving force

Edit: Fixed some stuff I hadnt checked in my rush to post before the site crashed again



mate.... your diff must be totally different to mine then...... because i have used "poor mans locker" and it worked.... more than once too :)

No one has truly got it right yet, the closest I know of is Sam Overton's traction control.


So are you gunna re-invent the locker and prove many people wrong???

[Humpy]

So are you gunna re-invent the locker and prove many people wrong???


I wish I could, I'd be Rich ;D

Unfortunately even though it would seem easy to do, its a really complicated thing to achieve, plus it has to fit in a small space, be strong enough for people like us to abuse and be relatively cheap to manufacture and service.

[HnM]

Test still not done Paul

[Humpy]

Maybe if you get your shite back together for the forum trip you can test it then with a dozen or so witnesses

[HnM]

And a few beers as a wager at the local ;)

[Humpy]

Righto your on

didn't get his stuff together for the big test :-\

i'm a poor man and my locker worked LOL

[taziiy]

there is always the next one ;D

[HnM]

I have lsd's front and rear now though :-\

I will have to convince someone to remove their rear shaft for the test eh

[taziiy]

Its bben that long now i cant remeber what you where going to do to test this thery :o

[HnM]

Its bben that long now i cant remeber what you where going to do to test this thery :o


Remove the rear shaft and pull the handbrake. Select 4WD and lift both wheels with a jack. Leave one wheel with just a lil weight on the ground....

Now select low first and idle....then slowly press the brake and see if the other wheel starts to move.

That is my interpretation of the test and I beleive the other wheel will definately move ;)

[taziiy]

Ok so when you coming down here to test this thery out and will vidoe it at the samer time :D

there ya go....... ya got a vehicle to test the theory on ;D

[HnM]

Ok so when you coming down here to test this thery out and will vidoe it at the samer time :D


Dunno mate, when I get some cashola for a run I will come down or maybe when these axles are back in mine

why dont you just toss this theory out the window, and turn them into real poormans lockers, just weld em up

[baby_troupe]

I've been using my poor mans locker :D

when crossing a log, I lock the rear ARB & then left foot brake over the obstacle :D

Makes it nice & slow

[Humpy]

Ok so when you coming down here to test this thery out and will vidoe it at the samer time :D


Dunno mate, when I get some cashola for a run I will come down or maybe when these axles are back in mine


There is a travel ramp in front of Overkill engineering, Which is just up the road from the Bluegum, where we had the last drinks/meetup


I've been using my poor mans locker :D

when crossing a log, I lock the rear ARB & then left foot brake over the obstacle :D

Makes it nice & slow


What you're doing is trying to get some control back from the auto gearbox, it is unrelated to lockers, plus you have a rich mans locker :D

[HnM]

My theory only involves moving drive to the other wheel for this test Paul. Basically proving that this bit of drive could definately help..........

doesm't mean it is going to lock both wheels with equal drive and work exactly the same as a locker but simply allow a lil more drive to get you up a small obstacle not a 45 degree ramp to the top.........

[Humpy]

Starting to get scared now are we Craig :P

I still don't think it will work

[HnM]

Theres no scared Craig'o in here Paul, check the thread. All I propose is that there will be drive fed to the opposite wheel ;)

And it will work, I will bet my mother on it and trust me you don't want her ;D

[taziiy]

Ok no i have a problem how do you go with a manual you dont have 3 feet :o

Ok no i have a problem how do you go with a manual you dont have 3 feet :o


it's easy...... if you are having traction problems, you don't want your left foot near the clutch..... use that foot ;)

[Sea-Dog]

I didn't finish reading the thread but I was towing the camper through some soft sand at Rainbow Beach and was burying down until I lightly put my foot on the brake.. car gave a bit of a shudder and then took off again... I don't think it was coincidence that it worked either.....

Now I am getting ARB Air Lockers front and rear so it won't matter anyway!

further proof it works eh? ;) ;D

[Humpy]

further proof it works eh? ;) ;D


Maybe, Probably not :P

[baby_troupe]

What you're doing is trying to get some control back from the auto gearbox, it is unrelated to lockers, plus you have a rich mans locker :D

True, and boy is it smooooooooooooothe

[taziiy]

and what if you have a manual that doesnt come into it ;)

[westvictoriaHILUX]

Hey thats very interesting. I would have never thought to do this. When i have wheel slippage i normally go back down the hill, rock, mud or whateva it is and go back up harder so the force of the vehicles wieght and roll push me through the obsticle

[HnM]

Momentum breaks things





But its so damn fun sometimes ;D

[taziiy]

But you need momentum to move forwards ;D

[Humpy]

As soon as you move you have momentum ;) ;D

kinetic energy ;D

[Humpy]

You always have inertia ;D

as apposed to potenial energy 8)

[terra]

(part 1)
I’ve been thinking about this “poor mans locker”
People like Roe have done practical experiments in the field and say it works, I believe them. Others have had poor outcomes when they try the technique, I believe them.
So it works, but not always.
There was a question as to how it works if the rear brakes apply the same force each wheel, won’t the drive still go to the wheel with the lower resistance, the one that has already lost traction? This is a fair question and got me thinking, there must be more to it. ???

I think there is….

You have to remember this situation is a dynamic system.

For simplicity consider an open rear diff, (non LSD), 2wd vehicle which has lost traction on one wheel and that one wheel is ‘spinning’ with the vehicle stationary. (2wd for simplicity, or let’s only consider the rear axle of a 4wd).

Now the spinning wheel will happily spin and expend all the available torque unless we can find a way to get a bit of this torque to act back over to the stationary wheel. To do this we need to get some torque resistance onto the spinning wheel to trick it into thinking it has traction, until the loads on both axles are close enough to equal so the vehicle starts to move forward. (= acknowledge Newton’s second law to gain forward movement).

But how?

We know that when both wheels have 100% grip and are driving together in a straight line, the diff centre will be turning at the same speed as both axles.

We also know that when one wheel is stationary and the other is spinning, due to lost traction, the spinning wheel rotates at twice the speed of the diff centre (due to the spur gears in the diff multiplying the speed).
Now in physics you don’t get something for nothing, therefore by doubling the speed of the spinning wheel, the spur gears are also halving the ‘effective’ torque to the spinning wheel when compared to the stationary wheel.
This speed/torque relationship could be the reason why in “some” situations the poor mans locker technique will drive you out of trouble. (I’ll get to the “some” bit later).

But WHY is this the reason why it works…

With a correctly functioning brake system the torque resistance applied to each wheel of an axle by the brakes should be equal, or damn close to it. However the brake has twice as much ‘effective’ torque resistance on the spinning wheel than it does on the stationary wheel (because the spinning wheel’s torque is halved due to its doubled velocity as stated before). So the brakes effective torque resistance on the wheel is proportioned 2:1 (spinning wheel = 2, stationary =1). As the stationary wheel starts to rotate, the ratio drops below 2:1, until both axles are rotating at the same speed and the ratio becomes 1:1.

[terra]

(part 2)

So, you correctly apply your “poor mans locker” technique and…

The vehicle will move forward IF the torque required by the stationary axle to get the vehicle moving is less than the extra torque resistance applied to the spinning wheel by the brakes.
That is if torque required to move equals less than the difference between 2x brake force (spinning wheel) and 1x brake force (stationary wheel) you will start to move.
However, if the torque required to move the vehicle is more (hill too steep, hole to big etc) then the spinning wheel will keep spinning (or you will stall the vehicle/break something). This is why the technique will work in “some” situations.

So it appears that it’s the rotational speed difference of the axles that may let this technique work.
This means you want to keep the wheel without grip (the spinning wheel) spinning fairly fast so that the torque resistance ratio is working in your favour and up near the 2:1 end of the scale. Hopefully this will allow the wheel with grip to start slowly rotating and SLOWLY drive you out of, or over, the obstacle. Remember the closer the speeds of the wheels are, the less torque multiplying advantage you have to let the brakes do there thing and transfer drive across.
So it’s a dynamic system and a balancing act at best, it’ll get you out of SOME situations.

I ‘spose it’s called a “poor mans locker” because the “rich mans locker”, a real one, is better and will ensure drive to both wheels of the axle in ALL situations.

What about if you have a decent L.S.D in the diff? Well, lucky you. All this applying brakes and loading up the differential gears should have an added effect of helping an LSD do its thing and limit relative rotation between diff centre and axles, which is a good thing and should enhance the ability of the “poor mans locker” technique to get the stationary wheel rotating and drive you out of trouble.

There are other factors involved in this technique such as static/dynamic friction coefficients, component inertia etc that can help or hinder the process but they will only muddy the already murky waters of my explanation.

The above is an explanation of why it might work, not a thesis on how it DOES work. If I’m right then do me the courtesy of crediting my explanation. ;D


Take care out there.
Terra.

WOW! :o LOL i almost understand all you said there! it makes perfect sense...... but i doubt that you will ever convince humpy of it no matter how hard ya try!! ;)

[HnM]

I think the experiment needs to be done and I have left my rear shaft out for that reason ;)
Now I just need a $12 handbrake cable and I will show him with video ;D

[Humpy]

Damn it roe is right >:(























































your not gonna convince me

I will think about your theory tomorrow and disprove it ;D

[Humpy]

OK, ive thought about it and since you guys dont trust me, i will give you some links to a website that helps explain my argument

Brakes, and the fact friction is greater on a stationary wheel
http://auto.howstuffworks.com/brake4.htm

Diffs
http://auto.howstuffworks.com/differential.htm

Locking and torsen diffs, Hummer's use of the poor mans locker
http://auto.howstuffworks.com/differential10.htm

Edit: link added

The owner's manual for the Hummer proposes a novel solution to the problem of one wheel coming off the ground: Apply the brakes. By applying the brakes, torque is applied to the wheel that is in the air, and then five times that torque can go to the wheel with good traction.

Kinda what we been saying all along ;)

[taziiy]

The owner's manual for the Hummer proposes a novel solution to the problem of one wheel coming off the ground: Apply the brakes. By applying the brakes, torque is applied to the wheel that is in the air, and then five times that torque can go to the wheel with good traction.

Kinda what we been saying all along ;)


with out reading the whole article just that bit that tony has there looks like it just shoot humpy in the foot ;D

[Humpy]

You didnt read the bit about the Torsen diff as fitted to a hummer, it splits torque 4:1 or 5:1 allowing the poor mans locker to work.

It also confirms what ive been saying about open diffs splitting torque equally between the axles at all times.

We were discussing the poor mans locker in relation to a standard open differential. Unless HnM has a torsen diff fitted his experiment is gonna fail :P 8)

[terra]

This subject popped into my head again whilst I was at a christmas gathering at the in-laws (amazingly I can nod and smile at relatives, AND think about 4WDs at the same time ;)).
I'm now doubting one of the reasons I based my thinking on. I'll have to go back to basics and have another think. I'll have to read those articles above too.

The spur gear acts equally on both axles (they effectively push against each other... thanks again Mr Newton) so that says that torque has to be equal on both axles always, regardless of speed. This was where I was in error whilst trying to work out how it might work. Maybe it works simply using the spinning wheels inertia as you brake it and let it accelerate again?

[HnM]

You didnt read the bit about the Torsen diff as fitted to a hummer, it splits torque 4:1 or 5:1 allowing the poor mans locker to work.

It also confirms what ive been saying about open diffs splitting torque equally between the axles at all times.

We were discussing the poor mans locker in relation to a standard open differential. Unless HnM has a torsen diff fitted his experiment is gonna fail :P 8)


Me no fail Mr Humpmiester ;)

[Humpy]

You may be on to something with the inertia of the spinning wheel there terra :-\\

Hmmmm

uh oh!!! Humpy is gettin scared now craig!! up the ante while you can!! ;)

[HnM]

Should get you and him over through the holidays eh, gunna buy a nice new handbrake cable today to help the test along ;D

[HnM]

I am ready to do the teat if someone will give me a quick hand bleeding the brakes ;D

[Humpy]

I should be free boxing afternoon

[HnM]

I should be free boxing afternoon


And I shall be pissed after the boxing day races ;)

GO TEAM GREEN AND GOLD ;D

But if ya still keen its not like I'll be driving it anywhere ;)

[Humpy]

Not gonna make it Craig

Maybe later in the week

[arfaname]

I could send you all to a link on another forum about just this argument but it requires you to read 12 pages of dribble. I have jacked mine up in all directions since to prove and disprove various arguments ( 80 series auto gxl)

k

Fact: torque is the amount of pressure required to "rotate" the said item. ie wheel.

If you have lost all traction on a wheel then in effect you are transfering little torque to that wheel as it has little resistance and therefore requires little pressure.

If your other wheel is stationary but has full traction it will require a lot of torque in order to make it rotate.

so lets say you have 3 wheels with full traction and one wheel in the air.

If your engine can produce 400nm of torque it does not mean that when you rev it in neautral it will produce that. It will only produce enough torque to "rotate" the free running parts.

So all 3 are good and one in the air.

The one in the air (assuming CDL is off) is spinning rapidly with little resistance. The torque required to do this is minimal (lets say zero) . The one on the ground with traction is going to require a lot more torque to move.

Being that an open diff will distribute torque to the wheel of least resistance you go nowhere. If you were to apply the brakes and achieve what would essentially be an equal resistance (for a split second) the torque would be transfered to those wheels equaly at lets say 50nm per wheel. If we then take into account that one of those wheels requires infact a further 50nm of torque in order to rotate then we have a situation. No matter what, as long as the free wheel has the brake applied it requires 50nm to turn and as long as the traction wheel has brakes applied it requires 100nm to rotate. Now if we go back to humpys theory of 0 torque = 0 drive then surely as long as you can maintain 50nm on the free wheel you will create movement on the free wheel.

Back to the open diff: as it is always trying to transfer torque to the wheel of least resistance it will spin both and will continue to try until one wheel has little or no resistance .In this situation we do not have anything with a resistance of zero it would transfer 75% of drive to the 50nm required on the free wheel and 25% to the wheel with traction.

As long as you have ANY decent amount of resistance on both wheels (equal or not) you will create drive on both wheels. It may not be equal amounts of drive but surely some is better than none..


now this all makes sense to me in my head but I hope I have explained it well enough for you to follow.

Try it fellas. Jack up one of your driving wheels on an open diff, get it spinning and try it again with the brakes on. It will drive off the jack. Full time 4wd leave CDL unlocked and in part timers your gonna have to drop the rear shaft or suttin unless you have no rear lsd or your 2wd is fwd.

give it a crack.

[Jys5428]

I could send you all to a link on another forum about just this argument but it requires you to read 12 pages of dribble. I have jacked mine up in all directions since to prove and disprove various arguments ( 80 series auto gxl)

k

Fact: torque is the amount of pressure required to "rotate" the said item. ie wheel.

If you have lost all traction on a wheel then in effect you are transfering little torque to that wheel as it has little resistance and therefore requires little pressure.

If your other wheel is stationary but has full traction it will require a lot of torque in order to make it rotate.

so lets say you have 3 wheels with full traction and one wheel in the air.

If your engine can produce 400nm of torque it does not mean that when you rev it in neautral it will produce that. It will only produce enough torque to "rotate" the free running parts.

So all 3 are good and one in the air.

The one in the air (assuming CDL is off) is spinning rapidly with little resistance. The torque required to do this is minimal (lets say zero) . The one on the ground with traction is going to require a lot more torque to move.

Being that an open diff will distribute torque to the wheel of least resistance you go nowhere. If you were to apply the brakes and achieve what would essentially be an equal resistance (for a split second) the torque would be transfered to those wheels equaly at lets say 50nm per wheel. If we then take into account that one of those wheels requires infact a further 50nm of torque in order to rotate then we have a situation. No matter what, as long as the free wheel has the brake applied it requires 50nm to turn and as long as the traction wheel has brakes applied it requires 100nm to rotate. Now if we go back to humpys theory of 0 torque = 0 drive then surely as long as you can maintain 50nm on the free wheel you will create movement on the free wheel.

Back to the open diff: as it is always trying to transfer torque to the wheel of least resistance it will spin both and will continue to try until one wheel has little or no resistance .In this situation we do not have anything with a resistance of zero it would transfer 75% of drive to the 50nm required on the free wheel and 25% to the wheel with traction.

As long as you have ANY decent amount of resistance on both wheels (equal or not) you will create drive on both wheels. It may not be equal amounts of drive but surely some is better than none..


now this all makes sense to me in my head but I hope I have explained it well enough for you to follow.

Try it fellas. Jack up one of your driving wheels on an open diff, get it spinning and try it again with the brakes on. It will drive off the jack. Full time 4wd leave CDL unlocked and in part timers your gonna have to drop the rear shaft or suttin unless you have no rear lsd or your 2wd is fwd.

give it a crack.

Wow, you know all this stuff and yet you still drive into little mud puddles and get bogged to the $hitter.http://members.westnet.com.au/klown/emotes/nutkick.gif
Sorry couldn't help myself

[brokelux]

why dont you just hook up two handbrakes
(or Four)
one for each wheel

[DoctorI]

why dont you just hook up two handbrakes
(or Four)
one for each wheel

sure!
and then all you need is a set of sensors to tell you which wheel is spinning...
oh, oh! were half way to automatic traction control and all of its problems.

[Bucko]

;D ill tell you the definition of a poormans locker !@!!
weld up the spiders !!!! constant and all 4 wheels spin till the welds break!!
lol1


Did that on an old RWD Mazda 323. Was amazing where it would get to. Especially after it was rasied up a few inches when I squeezed Commodore Rear coils into each corner of the Mazda.

Off Road fun for under $800 with a few months rego.. ;D

[timbocruiser]

tried this poor mans locker theory out in the mud the other week. didnt do nuffin for me but i didnt try it usingf the handbrake and im pi$%ed i didnt, it may have worked, i tryed it out withmy 80 on its side with weight off both wheels on same side and in a bog hole with even weight distribution, didnt work on either account and my mates werent happy either, they had to pul me out! ;D

i think it has a lot to do with the make of the vehicle.... i got it to work in the Deo in 4WD.... but i couldn't get it to work in a mazda bravo...... i actually tried it in 2WD in the deo, and it wouldn't work..... it's LSD....... but like it's name, it's LIMITED slip..... i got one wheel turning, and applied the brake slowly, all it did was stall the engine. in 4WD though, it worked. can't do it now with the locker in though.

[arfaname]

only just saw that Jamie..

Oh well.. 2morrow night when your hunting for the fellas in the dark may a big ol possum shite on your windscreen.. lol

I basically have 2 open diffs in mine Jamie. The rear LSD is shagged.

Have a top weekend mate.

Spewin I cant go.



Sean

[cpt-mud]

i thought i had a poor mans locker in my old 4by , a mig welder