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[05omegav6]

So far bushes and arms are holding up fine

Obviously if it all goes Pete Tong, I will let you know...

[elvin315]

Next step is to fit the same 'Black' bushes.

But I have a couple of modifications to consider following Chris's comments in April and Razzos latest issues

Fit the Black bushes, but sliced in half so the 'flanges' can move relative to the centre bush, reducing the rigidity slightly, but allowing some slip whilst supporting the arm vertically. So hopefully this will be the final solution, along with ensuring that the weld around the bush support is continuous and both sides so that the arm itself doesn't flex so much.

Isn't the Black Series stiffer than their Yellow? Wouldn't they be easier on the wishbone than the Black? You mention slicing the bushing in half but how exactly? They already come from PowerFlex as 2 pieces. Are the bolts 14mm and do you use the washers shown in your application? A little more detail please.

[chrisgixer]

Yes the yellow ones would be easier. But they don't control the wishbone position well enough. Too soft.

We then fitted black in the centre with yellow on top. Black worked out as the yellow was too soft,

Ultimately, as Al has now I believe/last I heard, it was black throughout.

Black are rock hard, like plastic or nylon. But they do hold the wishbone correctly, at the expense of flex, hence they transfer stress to the wishbone.

Here one of my attempts. Failed miserably. As the yellow is so soft it parted on the brakes and allowed the wishbones to knock on the subframe with appalling instability.

[05omegav6]

The yellow are too soft, as the deform under load. The blacks offer much better lateral support under braking/steering loads, whilst the flanges are pliable enough to allow the wishbone to pivot as per the originals

The bushes do indeed come as two halves Mine have been sliced horizontally so the flange and the part that sits in the wishbone are separate, hence four parts

The reason for this is due to the way I trialled the bushes...

MK 1. Yellow bushes fitted intact. Too soft, with control issues during braking/cornering.

MK 2. Black bushes sliced, with the core fitted to the wishbones, using yellow flanges as it was felt that the black flanges might be too hard. Better handling, but still odd characteristics under load, as the yellow flanges were deforming, allowing the arm to move vertically in the subframe, not ideal.

MK 3. Yellow flanges swapped out with the black ones. Effectively four layers, this allows an amount of slippage as the arm pivots under load, so the arm is supported adequately but is not locked in place.

Car is set up with zero toe, as per Wheels in Motions' advice, jury is out as to whether it needs some toe or not, but steering is as pin sharp as a steering box allows, (so it is a little vague in a straight line when the steering box is slack). However chuck it into a corner, and the steering weights up nicely with a reasonable amount of feel

With regards the Power flex kit, you can file the dished washers into a box in the shed/recycling bin. The stainless bushing is needed but requires 1mm to be ground off each end as it's a touch too long. I have also fitted a sleeve to mine as the ID of the steel bushings is 16mm (against 14mm for the bolt). This technically isn't essential as the clamping force of the vertical bolt should hold the bushing securely in place. For this sleeve I used a 15mm copper pipe cut 1mm shorter than the bushing and sliced along its length

Hopefully that answers most questions, but if you think of any more, just shout

[chrisgixer]

Here's one of Al's

[05omegav6]

 I wonder Chris, if it's worth revisiting your idea, but with black bushes and drilling them out slightly from the outside face to the depth of the flange once you have scalloped them. Don't slice them though, as the ball should eliminated the need for layering

[chrisgixer]

I wonder Chris, if it's worth revisiting your idea, but with black bushes and drilling them out slightly from the outside face to the depth of the flange once you have scalloped them. Don't slice them though, as the ball should eliminated the need for layering

Not with you from drilling, Al, sorry. Run that by me again?...

[elvin315]

Since Taxi Alsuggested revisiting Chrisgixer's Ball Joint design I sent an email to DayStar regarding their 2.0 Inch Poly Flex Joint - Part Number: KU70001BK. Both designs are similar so I asked:

What is the Shore Hardness of the poly races?
What is the Outer Shell height?
What is the length of the Ball Insert?
Can the shell be machined down to a 49mm OD?
Can the Ball Insert be drilled to accept the 9/16 inch Bolt & Tube?
What is the maximum angle of articulation?

Maybe their joint will work if we get the right answers. I won't receive anything until maybe tomorrow so stay tuned.

The link below is to a diagram showing the different joints and their assembly. Unfortunately it doesn't include dimensions.
http://www.daystarsuspensionparts.com/Installation_Instructions/Daystar/P10855-00.pdf

[chrisgixer]

I wonder Chris, if it's worth revisiting your idea, but with black bushes and drilling them out slightly from the outside face to the depth of the flange once you have scalloped them. Don't slice them though, as the ball should eliminated the need for layering

Not with you from drilling, Al, sorry. Run that by me again?...

Spoke to Al on the phone, he's talking about potentially making this in black poly, but by shaping the top and bottom of the bush, so as to allow it to rock with the the wishbone tilting action, but still stay firmly in contact with the roof and floor of the subframe bracket to prevent it working out.

That shaping could consist of a curved surface, like a cam, but with a constant radius. Issue I see there is, that of the bush is rubbing on the subframe it could be turned in the wishbone buy the rocking action. In effect, the poly will no longer be symmetrical. Therefor it would need to be fixed to hold it in the correct orientation, either pinned (tricky as we don't want to be drilling through the wishbone) or bonded (tricky again as poly is by definition pretty friction free)

Or, that shaping could consist of a cone shape to the top and bottom of the bush. But then there's less material to stop the bush halves working out, and increased likely hood of wear.

Thinking further, there would need to be a counter sunk shape to the top and bottom of the hole to allow it to tilt on the bulb shapes spacer without unseating the black poly, and keep the stress away from the wishbone.


Here is a pic of how the poly was shaped to match the bulb in the centre spacer, which was taken from the centre of an oe rubber bush. These vary greatly is size and shape among the aftermarket wishbones, and to a lesser degree the ie ones as well.


Obviously this is by no means accurate, but for the purposes of experimentation, it worked. Great care is needed not to go too far when holding the poly on the drill by hand, that the part doesn't melt too far and become too big, or that there's no injuries or burns. Thick gloves needed.

Later a lathe would be used if successful to gauge turn spead and depth. ..." IF "

Its a bit if a bodge frankly, but there we are.

Hope helps is anyone wishes to pursue it. But for the cost and effort, I chose to stick with oe rubber bushes. Tbh.

[chrisgixer]

?

http://www.mcgillmotorsport.com/m14-spherical-plain-bearing-gek14t-teflon-lined-889/

Would need a collar to fit. A poly collar maybe?

[chrisgixer]

Also talks about Teflon. Can't see much shock protection though.

Oe bush has roughly 4mm depth of rubber all round.

[Kevin Wood]

Also talks about Teflon. Can't see much shock protection though.

Oe bush has roughly 4mm depth of rubber all round.

There will be a thin teflon coating between inner and outer parts to prevent wear. There's no shock cushioning whatsoever.

They would probably need dust covers for protection too, but if you could sleeve it such that it's an interference fit into the wishbone and space the inner section to locate it centrally...

[chrisgixer]

Yes it would need to press in with similar tonnage as the oe bush. Which was about 1 ton of pressure last time I looked, although that probably varies greatly. It took about a ton of pressure to press razzo's polys put of TB's wishbones, btw. With the centre spacer still fitted.

Defo needs a gator or dust protection. They gather an awful amount of dust sand and gravel obviously.

.....Not to mention water . Which could be an issue.

[chrisgixer]

And spacers to and bottom to make up the 46mm height. Of course.

I'm still a bit concerned about the amount if contact with the ball. Re popping out.
Its better though. Or is it just me?

[chrisgixer]

Dust cover in this caught my eye. Second pic down.

http://www.smartuki.com/prices.php

Looks moulded on though...?