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Posted: Sun Jan 30, 2005 7:40 pm
by redzook
RUFF wrote:Tim is spot on the money his set up is no different to a normal set up its just how some people look at it.

Only reason the shaft would vibrate is if its out of ballance or out of Phase.

Trucks run the shaft between the rear axles(Dual axle combination) with a very similar set up and they work fine for hundreds of thousands of Kilometers.


thanks Tony
im glad some one can think a little :finger:

Posted: Sun Jan 30, 2005 7:43 pm
by BOGAN V8
dont really know KRAWLA will have to answer that ???? redzook i only helped build it i didnt design it.......

Posted: Sun Jan 30, 2005 7:45 pm
by redzook
BOGAN wrote:KRAWLA had same issuses with his using hilux diff with zook transfer offset heaps ended up putting in bundera diff and high pinion in the rear help out the vibration heaps almost not existant........


BOGAN wrote:all i know is KRAWLA put bundera rear housing instead of hilux and vibration gone

please explain it


wich one is it?

either way the reason i belive he has less vib is that he has a high pinion

also im pretty sure the bundera dosent line up exactly? it actuall goes the other way a little

Posted: Sun Jan 30, 2005 7:48 pm
by Busiboy
OK one last go,

you are running on two planes, the one angle you talk about is made up of these two planes.

the angles add up on these two planes to give you and increase angle on the one plane you are talking about.

read my earlier post and it sort of explains how they add up.

Posted: Sun Jan 30, 2005 7:50 pm
by DaveS3
Busiboy wrote:OK one last go,

you are running on two planes, the one angle you talk about is made up of these two planes.

the angles add up on these two planes to give you and increase angle on the one plane you are talking about.

read my earlier post and it sort of explains how they add up.


Thats pretty much what ive come to.

Its all in the planes ;)

Dave.

Posted: Sun Jan 30, 2005 7:53 pm
by BOGAN V8
there is still going some vibration as the car sits high but the vibration was a lot less once the bundera diff went in

and what ever vib is left (WHICH IS VERY LITTLE) is prob helped along by the sheet metal in the back making noise


Bundera diff would have to be a lot better than using hilux

yes you are rite hi pinion centre helps out a lot in this situation

Posted: Sun Jan 30, 2005 7:59 pm
by Guy
From what I can tell it is due to the way that the torque is applied back through the T/Case.
In the stock setup the mounts are designed to cope (barely) with the torque applied in a certain direction. ( ever action has an equal and opposite reaction stuff)
Now the shaft is on a different angle to what it was from factory, so it is trying to twist the case on its mounts a little as the line that the torque is taking back through it is different, the shaft is causing a "sidewinder" like effect and lifting the T/case cusing odd Uni angles..




refering to the post about swapping the Lux rear for a bundy rear, you also said he swapped in a High pinion centre, the uni angles will therefore be less .. so the swapping of the housing may have sweet FA to do with anything.



















All that said. I could be wrong. :D

Posted: Sun Jan 30, 2005 8:02 pm
by BOGAN V8
refering to the post about swapping the Lux rear for a bundy rear, you also said he swapped in a High pinion centre, the uni angles will therefore be less .. so the swapping of the housing may have sweet FA to do with anything.


i think he had the hi pinon in the hilux diff aswell before the swap....and they were still there (DONT QUOTE ME ON THIS) :) :) :)

Posted: Sun Jan 30, 2005 8:25 pm
by Dozoor
If the shaft is a normal shaft eg : two unis Just forget about the offset from the transfer its flange and the pinion flange should be square to each other on that plain, then work on your angles in a normal way tilting pinion /spacing transfer to achieve equal angles on that plain ect .
If it is a cardan joint used with this setup (offset transfer )
i think you,ll be extremly lucky to get any joy :?
you just won,t get it into the right angles . they are specificaly designed to piont either one but not both of the flanges directly at its opponent and you can,t do it with the offset transfer..

I Have witnessed the out of phase that should have shook its butt Off, but didn,t ,funny how wierd shit works some times. :lol:

Posted: Sun Jan 30, 2005 9:02 pm
by MARKx4
After all this chating and ideas, Wouldnt it be easier to cut and offset the diff you want to put in, instead of going to all the trouble sorting out a vibration problem after you have done all this work? tell me if i wrong, thats just my thoughts. :armsup: :armsup: :armsup:

Posted: Sun Jan 30, 2005 9:39 pm
by turbo4t
Slightly off the topic but I have this retarded customer who wants his Landcruiser 60s converted to 2WD with a Ford V8 & auto. I told him to buy an XD. He's going to pay pretty big $ to have the pumpkin moved to the centre to avoid these problems. There's one born every minute.

Posted: Sun Jan 30, 2005 10:20 pm
by Shorty40
redzook wrote:
RUFF wrote:Tim is spot on the money his set up is no different to a normal set up its just how some people look at it.

Only reason the shaft would vibrate is if its out of ballance or out of Phase.

Trucks run the shaft between the rear axles(Dual axle combination) with a very similar set up and they work fine for hundreds of thousands of Kilometers.


thanks Tony
im glad some one can think a little :finger:


I disagree.

You have two angles there Tim.

Put simply:

Looking from the transfer case to the diff.

In a normal rig you have one angle - lets call it 'DOWN'

In Tims you have two angles - 'DOWN' and 'RIGHT'

Tim - even if you tip your car on its side, as you say (lets say passenger side), you will still have two angles - 'DOWN' and 'LEFT'

Posted: Mon Jan 31, 2005 6:18 am
by Wendle
love_mud wrote:From what I can tell it is due to the way that the torque is applied back through the T/Case.
In the stock setup the mounts are designed to cope (barely) with the torque applied in a certain direction. ( ever action has an equal and opposite reaction stuff)
Now the shaft is on a different angle to what it was from factory, so it is trying to twist the case on its mounts a little as the line that the torque is taking back through it is different, the shaft is causing a "sidewinder" like effect and lifting the T/case cusing odd Uni angles..


shouldn't matter, torque is torque, it is still being applied in the same direction from the same spot.

there is only enough moving parts in universal joints for them to have 1 angle each. when the flanges are offset that angle just has to be divided across two planes, the angle becomes compound instead of linear.

Posted: Mon Jan 31, 2005 10:46 am
by antt
Shorty40 wrote:
redzook wrote:
RUFF wrote:Tim is spot on the money his set up is no different to a normal set up its just how some people look at it.

Only reason the shaft would vibrate is if its out of ballance or out of Phase.

Trucks run the shaft between the rear axles(Dual axle combination) with a very similar set up and they work fine for hundreds of thousands of Kilometers.


thanks Tony
im glad some one can think a little :finger:


I disagree.

You have two angles there Tim.

Put simply:

Looking from the transfer case to the diff.

In a normal rig you have one angle - lets call it 'DOWN'

In Tims you have two angles - 'DOWN' and 'RIGHT'

Tim - even if you tip your car on its side, as you say (lets say passenger side), you will still have two angles - 'DOWN' and 'LEFT'


this is what i always thought too, but now that i've spoken to tim about it him and tony are right, there is still only one angle on the uni's, just like a normal straight driveshaft

Posted: Mon Jan 31, 2005 11:27 am
by MY45
antt wrote:
Shorty40 wrote:
redzook wrote:
RUFF wrote:Tim is spot on the money his set up is no different to a normal set up its just how some people look at it.

Only reason the shaft would vibrate is if its out of ballance or out of Phase.

Trucks run the shaft between the rear axles(Dual axle combination) with a very similar set up and they work fine for hundreds of thousands of Kilometers.


thanks Tony
im glad some one can think a little :finger:


I disagree.

You have two angles there Tim.

Put simply:

Looking from the transfer case to the diff.

In a normal rig you have one angle - lets call it 'DOWN'

In Tims you have two angles - 'DOWN' and 'RIGHT'

Tim - even if you tip your car on its side, as you say (lets say passenger side), you will still have two angles - 'DOWN' and 'LEFT'


this is what i always thought too, but now that i've spoken to tim about it him and tony are right, there is still only one angle on the uni's, just like a normal straight driveshaft


Finally more are able to see the light....its exactly the same as normal and its imposible for it not to be. If you pick up a drive shaft you can move it into any position and itll still be the same, the only differance will be that one is rotated more than another.

Posted: Mon Jan 31, 2005 11:31 am
by Dozoor
There can only be one :)

taking your measurments at the most acute or obleak position on the shaft in comparison to the flanges, ;)

Posted: Mon Jan 31, 2005 12:09 pm
by Shorty40
I retract my previous statement ..........................

I have seen the light :D

Posted: Mon Jan 31, 2005 1:25 pm
by Tas_Dean
I'm no driveshaft expert, but it is only one angle and provided that ONE angle is not out of the universals working range, they should ge able to cope fine! For those who think differently, go and check out some PTO driven equipment on tractors! A lot of farm machinery is offset and down from the output shaft, and the uni's work fine!

Cheers, Dean

Posted: Mon Jan 31, 2005 4:04 pm
by carts
OVERKILL ENGINEERING wrote:okay if it is still one angle what causes it to vibrate then
SAM


I think you'll find this may be a combination of what 'love mud' was getting at and excessive uni angles. In a normal driveline setup, the reactive forces produced by the uni joints when near its limts wants to push the output shaft on the transfer case vertically. It is however supported by the mounts equally, which allows the transfer case only a small amount of movement in the vertical plane.

Perhaps, because you have now changed the axis of rotation on the driveshaft, the forces produced by over extended uni angles are no longer equally absorbed by the mounts on the gearbox. This would allow the transfer case to 'vibrate' in a vertical and horizontal plane causing excessive driveline vibration.

Just a thought. I've be racking my brain out on this one, but if anyone can give me a reason why this wouldn't happen, i'd be glad to hear it.

Posted: Mon Jan 31, 2005 4:35 pm
by Gribble
Hands up in here if your a certified mechanic and listened when you went to TAFE instead of smoking bongs in the dunny with all the valiant boys. :finger:

When you need to make an angle in a shaft you can do it with "universal joints", thats the ones with the cross and yokes, not a "constant velocity joint" which is the one with the round slingshot bullets you use when they shit themselves. There are a few others like hardy joints and the rubber ones used in commodores.

A universal joint is the simplest and cheapest style for its strength. We all know what they look like and how they work, so i wont go into its construction too much. The biggest downside to a universal joint is that when the 2 shafts form an angle between them, the driving shaft stays at a constant speed whilst the driven shaft accelerates and decelerates 2 times for every rotation of the driven shaft. When both shafts are parralell and running on the excact same axis this speed difference doesn't happen, it only happens when there is an angle between 2 shafts.

To overcome this problem is dead simple, put another universal shaft at the the end on the driven shaft and run a 3rd driven shaft parallel to the driving shaft. This uni joint is not working in the complete opposite of the first one. Where as the first one is accelerating and decelerating the 2nd shaft, this uni now decelerates and accelerates completely opposite to the first one, thus causing the 3rd shaft to be at the same speed as the first. Of course, providing that the yokes on the ends of the second shaft are parallel and that the unis are in the excact same angle.

This is what we try to aim for when we fit castor wedges to leaf springs or castor kits to your patrol or landcrushers front ends (the coil ones that is).
So that the 3rd shaft is now spinning the exact same speed as the 1st one.

So where does this vibration come from? I have aligned the 1st and 3rd shafts so that they are dead parallel? It should all be spinning in unisen?

The answer is simple again, the centre shaft is still accelerating and decelerating that 2 times every rotation. So its this weight of the shaft that the diff or gearbox has to accellerate and slow down that causes your vibration. You will always have this phenomona, unless your shaft is dead straight. Thats why manufactures always aim to have the shaft dead straight at the resting height of the suspension.

A constant velocity shaft is just that. No matter what angle the 2 shafts are at, there is never ANY variations in speed, whatsoever.

Ok, im going to the pub now. Brain needs beer. Anyone who didn't understand all that can feel free to come around to my house and consult my TAFE textbooks. Or carts you can come see me at the garage and ill show what i mean. ;)

Posted: Mon Jan 31, 2005 4:37 pm
by STUMPY
carts wrote:
OVERKILL ENGINEERING wrote:okay if it is still one angle what causes it to vibrate then
SAM


I think you'll find this may be a combination of what 'love mud' was getting at and excessive uni angles. In a normal driveline setup, the reactive forces produced by the uni joints when near its limts wants to push the output shaft on the transfer case vertically. It is however supported by the mounts equally, which allows the transfer case only a small amount of movement in the vertical plane.

Perhaps, because you have now changed the axis of rotation on the driveshaft, the forces produced by over extended uni angles are no longer equally absorbed by the mounts on the gearbox. This would allow the transfer case to 'vibrate' in a vertical and horizontal plane causing excessive driveline vibration.

Just a thought. I've be racking my brain out on this one, but if anyone can give me a reason why this wouldn't happen, i'd be glad to hear it.




i think what have said makes sense carts.

Posted: Mon Jan 31, 2005 4:41 pm
by derangedrover
OVERKILL ENGINEERING wrote:
spazbot wrote:are the unis in phase ?


good question we have done 2 vehicles with this setup a rangie with patrol diffs and a zook with lux diffs. with bothe trucks have the unis phased correctly vibrates like a C!!!! take the unis out of phase nearly perfect.
SAM


Dont forget Rangies driveline is offset in the chassis, ie engine is mounted left of centre, so your tcase output flange and diff input flange are not in the same plane, ie not square to each other, so it will be impossible to get equal and opposite angles on the unis. So, do what rover did with the front shaft and make the uni's out of phase until the vibes are gone or acceptable.

Have seen a tailshaft shop mock up a shaft, then with vehicle off the ground but suspension held at ride height (on jack stands), vehicle is run and tailshaft speed measured. Fabricator dicks around with phasing until the tailshaft/mounting flange speed is as constant as possible then they have a shaft with the desired out of pahse to produce no vibes and the make the real deal from there.

Cheers
Daryl

Posted: Mon Jan 31, 2005 7:08 pm
by bazooked
ok guys ive been in the tailshaft buisness for the last ten years, rangies are out of phase because of the offset transfer etc, we tried at work by putting the shafts in phase and had no joy, we then put em back out of phase and problem is fixed, we do alot of chasis extensions on trucks, if the shaft or shafts are not spot on with the centre line of the vehicle, they will vibrate there ass of, its just the way the dynamics of a uni work, its to hard to explain so im not goin into it. so to put it simply there IS 2 angles, up and down and left to right for us simple folk, and an offset diff to transfer will always vibrate!

Posted: Mon Jan 31, 2005 9:07 pm
by slosh
I've been running offset diff to transfer in my lux for a while now. Used pretty long one piece propshaft with double cardan joint on t/ case end.

Works fine, no vibes from 0- 130 km/ hr except when decelerating or coasting down hills. Somebody said this is caused by worn d/c joint.

Josh.

Posted: Tue Feb 01, 2005 1:58 pm
by Roctoy

Posted: Tue Feb 01, 2005 5:38 pm
by BOGAN V8
that takes too lon to read chris whats it say plain and simple......

Posted: Tue Feb 01, 2005 6:21 pm
by RUFF
BOGAN wrote:that takes too lon to read chris whats it say plain and simple......


Plain and simply it says exactly what i have allready said :finger:

Posted: Tue Feb 01, 2005 6:36 pm
by BOGAN V8
oh o.k :oops: :oops: :oops:

Posted: Thu Feb 03, 2005 3:39 pm
by OVERKILL ENG
RUFF wrote:
BOGAN wrote:that takes too lon to read chris whats it say plain and simple......


Plain and simply it says exactly what i have allready said :finger:


I can't see where it says about offset transfers . Or it being one angle. :D
SAM

Posted: Thu Feb 03, 2005 3:54 pm
by Patroler
If you really think that there is two angles, just fit the tailshaft, break out the welder and weld the uni's up so that they are rigid and can't go anywhere at all, take out the shaft and lay it on the ground on its side...
How many angles are there?


1 per uni