Cutting and welding solid axles to adjust diff & prop angles?

[pressbrake1]

You have to keep the diff flange alignment with the gearbox output, or you will get a lot of prop shaft vibration. I don’t think simply pointing the diff upwards is the answer.

Very true hence my mention of kinematics
A double Cardon prop will help with this or working out the kinematic and calculating a phased joint propshaft.
The problem with 4x4 is you can’t match both output flanges with the prop flanges at the same time so priority is given to the rear axle.
On most 4x4 a phased prop is used on the front though the discovery 2 has a double cardon prop on the front(cv joint)

 

[rcx132]

You have to keep the diff flange alignment with the gearbox output, or you will get a lot of prop shaft vibration. I don’t think simply pointing the diff upwards is the answer.

If it's pointing upwards at the same angle as the transferbox output then it is in alignment, using the Z configuration

Very true hence my mention of kinematics
A double Cardon prop will help with this or working out the kinematic and calculating a phased joint propshaft.

What's a phased prop? I've heard of it but I always thought it was a myth as none of my textbooks mention it.

The problem with 4x4 is you can’t match both output flanges with the prop flanges at the same time so priority is given to the rear axle.

Why can't both output flanges be matched? I thought on the donor car the rear prop was aligned in Z configuration, with the transferbox inclined to reduce the rear propshaft angle. The front prop was then aligned in "bridge" configuration to make use of the inclined transferbox angle. This is a problem on jacked up 4x4s as bridge configuration only works if the transferbox and front axle are at the same height. Hence the point of this exercise to rotate the front diff into Z configuration. I appreciate that this does no favours to the propshaft angle (due to the transferbox being inclined in favour of the rear axle), but it's a part-time 4x4 anyway, so the front prop is not turning when on the road. The front prop is only engaged off-road at low speeds.

 

[Morrisman]

If the front axle is being rotated to point upwards, then the motor must be pointed down to line up. I somehow doubt that is happening here.

All propshafts are phased, aren’t they? Or rather the UJs are on the ends.

 

[pressbrake1]

I’m sorry I can machine your axle apart but neither have the patience or command of written English to explain to you without diagrams nor gestures driveline angles and kinematics.

Nothing is perfect and one has to use other methods than simple hooks joints to overcome such issues

 

[rcx132]

I’m sorry I can machine your axle apart but neither have the patience or command of written English to explain to you without diagrams nor gestures driveline angles and kinematics.

Nothing is perfect and one has to use other methods than simple hooks joints to overcome such issues

No probs, I can read up on it. But are you saying that there are more possible propshaft configurations than the common and simple Z, bridge, and double cardon config (where the angle is in the double joint and the single UJ is set straight) ?

When you mentioned kinematics and phasing I thought you might be on about something that was once mentioned to me. My first 4x4, over ten years ago, went to a supposed specialist who fitted a "crawler" transfer box. The new box he fitted had the rear output flange offset from centre, while the original box had a centred rear output flange which lined up with the rear axle diff. So now the rear prop now had a compound angle. The shop had fitted a new double cardon prop at the rear even though there was a compound angle, which goes against the three configurations I was aware of (Z, bridge, and the double cardon with one UJ set straight). When i asked the specialist about this, he said something about phasing and that by rotating the propshaft by one spline (on the bit of the propshaft that lets it extend) that a prop can be put into phase. He was an angry fellow so I didn't ask any more. The car was written off straight after this so never even got to test the new configuration. I assumed he was talking rubbish, that it was some pet theory of his and left it at that.

So when you mentioned "calculating a phased joint propshaft" I thought maybe this was this?

 

[rcx132]

If the front axle is being rotated to point upwards, then the motor must be pointed down to line up. I somehow doubt that is happening here.

All propshafts are phased, aren’t they? Or rather the UJs are on the ends.

I think we are just mixing up our definitions of which direction is "rotated upwards". I'll draw a diagram later.