Rear Axle bracket problem?

[seajayare]

I have just started to build my XI and was planning to put the rear axle in first. I have run into a problem straight off with the brackets on the axle casing ( the ones westfield have put on ) that take the traing arms/panhard/shocks. The metal tubes in the rubber bushes in the trailing arms are 1.5inch long and the bracket on one side is only 1.4inch (panhard rod side) and the other slightly larger so the bushes won't fit. I can just get the bush in on one side with a hammer but there is no chance on the other side. Any clues as to what I am doing wrong or suggestions on what next? ( i dont fancy grinding down the bracket or the bush sleeves but taking the bracket off and remaking is a bigger job than I fancy doing.

cheers

[Westfield 129]

You are writing about the axle brackets, or the chassis brackets? Grinding should not be necessary for the assembly of the suspension.

The chassis bracket can be bent out a little for clearance. The holes may have to be reamed on the shear plate (the plate welded to the chassis that captures the bushings and trailing arm) for a perfect fit.

The axle brackets are the same left and right, or they should be. If the brackets don't fit the bushings, I guess you have to send the Westfield built axle back to have the narrow bracket replaced.

The trailing arms should be uniform as well. The bushings should all be the same width. Note that the trailing arms are offset, so check for proper orientation. The Panhard Rod has an adjustable end, so that the axle can be centered once the ride height is set (with the driver installed).

I occasionally make the brackets from billet on a CNC machine. They are quite accurate. The measurements were taken from an original Westfield laser cut and bent bracket.

There should be no difference between the left and right axle brackets, and the welding process at Westfield should not have any effect on the width. If there is a problem, send the assembly back to Westfield. If one bracket is measurably narrower than the other, it is defective and needs to be replaced.

[allymally]

Hi, Could you upload pictures please ? it would be helpful to see what is going on.
All the very best Malc

[seajayare]

Thanks for looking. I have tried to add some pics to the original post but they are not the best. On the panhard rod side I did try to persuade the busy into the bracket to see if it would bend things to fit... it didn't but it did mess up one side of the bracket by flaring it out which you can see on the pic.

cheers

[Westfield 129]

Square the bracket with the axle when you bend it out (a right angle square will work. Eyeball measurement is OK against the square straight edge). This should fix your problem. I would use a large crescent (adjustable end wrench/spanner, gripping the side of the bracket) to do the bending. The larger the grip area, the better. You don't want distortion across the bolt hole. A larger hammer may be used to persuade the flared out side of your bracket back into position, or you can use the wrench. You have to work both sides of the bracket to keep everything square with the axle housing. Feel free to bend both sides to get a nice, easy fit. This fit is important, as you will be taking out the rear trailing arms often to replace the bushings, and you want everything to go back together easily.

The bushing should fit into the bracket with finger pressure, or a slight tap with a soft mallet or small soft face hammer. If you bent it a tiny bit too much, not a problem once the bolt is installed and tightened.

This really is not a problem, and is easily rectified. "Some bending may be necessary...". The forks at the end of the front upper arms may also need to be bent slightly to accommodate the upper trunion bushings.

For some reason, the brackets are pinched and welded on your car. Not the best work... But easily fixed.

To see what a proper welding job looks like on the rear axle (TIG welded), check out the pictures of the rear axle assembly on my RHD build at westyxiownersbuildersdrivers at Yahoo. Lots of pictures . If you need anything else, let me know. https://groups.yahoo.com/neo/groups/Wes ... 1600954352

(Quick note: I don't recommend tightening the bushings as they really are vibration isolators in real life (The Lotus 23 uses them as part of the engine mount, pressed into the frame), and can't really take much internal rotational flex without shreading the inner rubber in only a couple of hundred miles. About 5 lb.ft. of torque is all that is necessary to make for a much better ride, more predictable handling and a much longer life for the bushings.)

I start with the front suspension, as it is easy, and you get a feeling accomplishment when you finish a complex structure. Also, you can work alone.

The rear axle usually requires a companion to help with the lifting and hanging. You may also want to mark and cut a hole for the diff in the rear floor pan to allow for more suspension travel when you go to longer rear dampers. BIG difference in ride and handling...

[Daggers-xi]

Having just finished assembling my rear axle for fitment to my XI which I started at the beginning of December and reading your post I have just rushed out to my workshop and measured my arms and axle brackets.
The brackets measure between 1.45" and 1.46" with the bushes at a constant 1.5". I am initially reluctant to distort my nice shiny brackets, thinking of setting arms up on the milling machine and shaving inner sleeves.
I have not yet measured the placing of the brackets on the axle but that will be the first job tomorrow.
Hope all goes well, your not alone, keep us informed.

[Westfield 129]

Don't bother. Just bend and tighten suspension bolts as necessary. This is not a critical part, as the brackets are tightened down on precise spacers, (the bushings) and the torque can be set by the freedom of movement of the trailing arm. You can set the tightness by moving the arms, or tightening until you get solid contact, then backing off slightly so that the car bounces nicely (the bushings rotating with the arms). Remember, the brackets are produced through distortion of the metal (its bent to shape). As far as distortion, well, they are welded onto the axle, and the heat of the MIG does some distortion as well. I specify TIG welding, as it minimizes the distortion.

Don't file, mill or otherwise change the thickness of the metal and weaken the bracket. Cold bend them if necessary, as that is how they were formed in the first place, and any bending you do will be minimal anyway.

Most of the time, the simple approach work best when building the W11.

The part that Westfield manufacturers (or its contractor) are just laser cut metal plates (I have the actual blueprints here, sent to me so that I could make my own brackets) that are folded on a machine (likely a press, using a die). Not that precise, but strong enough and perfectly adequate. The tolerances are pretty wide. Some bending may be necessary, but only if they are too wide. The suspension bolts can handle any extra clearance within reason. Feel free to add shim washers if necessary.

My own billet brackets are more precise, but this is only because I had CNC equipment to work with, rather than trying to laser, plasma or water jet cut the parts. Technical over kill (but I didn't have to make tooling to cut and bend the parts) and when I built the car, I used the factory brackets that arrived ahead of the kit. I have no regrets, and no problems fitting them to the axle, or to the suspension bushings and arms. I still have the very cool CNC axle brackets on the shelf. Maybe if I build another... Or if you want, I can sell the billet brackets for $250 a pair (they even have an index for the Panhard rod bolt) .Don't bother, as the standard Westfield parts are more than adequate, even if you have to bend them slightly.

[allymally]

Hello again thanks for the pictures.
The simple answer as you have had already, is to simply bend the bracket locally.
I do suggest that you inform Westfield of the problem so they can look into changing the way they do things, on future parts.
Poor quality control. If they have any at all.
5inches of 1.5inch x 1inch M/s bar with radius on leading edge, to tap into bracket which should bend the two sides out at an angle but quite evenly, then with the bar still in place tap the sides back square this should get you most of the way.
All the best Malc

[Daggers-xi]

Jan,
It's the the bracket that is too narrow so I was considering to accurately machine 0.025" off each side of the inner steel tube of the bush on the mill, and leaving the brackets as is.
I agree Malc it would make sense to make a wedge and distort the brackets locally, just goes against the grain. I'll make a wedge this morning and report back.

[Daggers-xi]

Wedge worked a treat.