Citroen Light 15 Rear Axle

Hi :)
I am glad you have discovered the backing for a torsionally flexible beam. A slit has been used before by manufacturers but has been lost to a google search engine.
My thoughts are that tackwelding it at intervals will just stiffen it proportional to the decreasing distance of the tacks and approaching the full stiffness as they approach full welding ? Why go there at all as minimal stiffness is desired ! The stress raisers of the tacks will cause problems in the long run.
Indeed my thoughts about it are really the details of the design and the welds will decide the stress points which in turn will determine the possibility of cracks. I would not use stainless tube.
Jaahn
 
I will be using stainless as it was only seamless suitable available near me plus I need my every day driver ~ on & not off the road.
From what one reads [& us old farts saw] these vehicles were run on goat tracks, across paddocks but now run on very good roads.
So much of the negatives become mute.
Will instruct not to weld or if done re-cut after finish.
These folk must consider liability & this is understood.
Not a hot rod, but goes well & will go better.
<500 km & I saw obvious drivers side rear tyre wear from excessive 4.6* toe in.
That will be fixed when we're finished.
 
The cupboard was bare
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Possibly tomorrow, I will have the rear axle fabricated & complete ready to install.

Then I'll post pictures & working diagram ~

John GIBBINS Citroen Rear Axle Instructions:

HUBS: Ford Falcon

1. Drill holes & fit hub studs to correct PCD for Holden Astra steel wheels 110mm x 5 studs

2. Skim hub OD to suit rotor ID for good support as this new hub ID doesn't support the rotor

3. Skim hub to wheel face for flatness before fitting studs

AXLE:

1. Make sure that the water jetted plates you now have fit over the stub axles un-machined portion because the calliper mounting brackets must do so afterwards & before the hubs are finally fitted.

2. Assemble & weld stub axles to the shaft endeavouring to keep everything straight & paralel so there are no in built steering angles

2. Drill 16mm hole @ both extremities of the planned slit.

3. Slit axle as discussed 2-3mm wide, right across joining from 50mm inside the inner 2 trailing arm plates.

4. Weld the 2 inner 8 hole plates [with the shock mounting] to axle with top hole in the vertical plane.

4a. The shock plate hole should be parallel with the ground.

4b. The angle on these plates & exposed M12 cuphead bolts thread should be inwards & to the front of the vehicle.

4c. Unless this bolt is very tight, weld around the cup

5. Weld the 2 outer 8 hole caliper mounting plates with the top hole in the vertical plane

6. Weld the M16 bolt for Panhard rod to the vertical bottom of the axle

7. Weld the split pinned [handbrake bell crank mounting] small piece of shaft to the vertical top of the axle

8. Weld 2 M8 bolts to the electric handbrake motor bracket

9. Fit & weld the bracket so the narrow U section is to the front of the axle, is on a line central on the axle & on the horizontal

9a. The longer U section leg will be uppermost on the top of the axle.
 
I don't know what it is about Gold Coast tradesmen?
This type of stuff happens all the time & one ends up having to do corrective work to fix issues that should not have happened.

Those following know I went to a lot of trouble to get the correct PCD of 88mm for the 8 holes.
The Water Jet folk were given a correctly dimensioned diagram & did a lovely job.
Unfortunately the finished product had PCD 80mm.

Luckily this was established before welding!
But more ~ they won't be back @ work until 18th January, so looks like I'll have to pay someone else to re-do this work.
Not all wasted as the 80mm PCD was on the 2 caliper plates & to be welded to axle mounting plate, so that can be used. JG.
 
Like others, I am interested to see how the finished engineering performs in your vehicle. Nice thread, glad you picked up on the error..
 
Well we are getting very close to final fitting up. It is bolted in & painted nearly ready to put hubs & wheels on then fit new hydraulic brake hoses bleed.
Sorry I was in such a hurry yesterday [I want my daily driver back] I didn't take photos after painting before fitting but will do my best today.
There will be a full write-up when done, for those interested.
Before fitting (2).JPGBefore fitting (6).JPGBefore fitting (11).JPGElectric Handbrake Bracket (1).JPGBefore fitting (7).JPG
 
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