Hi
A bit more progress this week ... It begins to feel like Im getting somewhere now although theres still masses to do.
Now that the main crossmember is in I have been working backwards setting up alignment of the cars rear end components.
I wanted to get the leaf spring front hangers correctly located first so that I could progress with the repairs to the rear floors and 'rear seat crossmember'.
The Jig I’ve made is in four parts... the first is bolted to the torsion bar rear mounting nuts at the rear of the crossmember and sets the datum height.
The second runs across the car and sets the height and width apart of the rear spring front mounts.
The third part fixes and sets the height of the rear leaf spring shackle pin mounts in the chassis rail. I’ve made this part with removable pins through the shackle mounting pin holes so I can replace the mountings without disturbing the jig settings.
The final part is a stout angle frame that is used to carry the datum level from front to back. (It’s the relative heights that are important – not the height from the ground)
There is a bit of a dilemma developing.......At the moment the middle of the car appears to be about 6mm longer than it should be despite this area having not being changed!!!
At this point I think Im going to have to live with the wheelbase being 6mm longer than spec!!!!
Here are some pics
- Rear Jig 040.jpg (1.9 MiB) Viewed 2621 times
- Rear Jig 039.jpg (1.65 MiB) Viewed 2620 times
- Rear Jig 041.jpg (1.76 MiB) Viewed 2620 times
- Chiltern-20110610-00245.jpg (1.12 MiB) Viewed 2619 times
- Chiltern-20110610-00246.jpg (1.28 MiB) Viewed 2619 times
- Chiltern-20110610-00247.jpg (1.38 MiB) Viewed 2619 times
- Chiltern-20110611-00264.jpg (561.91 KiB) Viewed 2619 times
- Chiltern-20110610-00257.jpg (2.12 MiB) Viewed 2619 times
- Chiltern-20110611-00262.jpg (448.09 KiB) Viewed 2619 times
I trial fitted one of the torsion bars on the drivers side. The position for this was previously set using a spare torsion bar made into a jig and set to 39” from the crossmember to the eyebolt centre in the chassis leg…….. Well the torsion bar fitted on fine but certainly doesn’t want to be set any more than 39” from the crossmember, as there is about 3/16” of the splines showing… though there’s still plenty of spline within the rear arm so I’ve decided that I’m happy with this positioning.
- Chiltern-20110610-00254.jpg (1.75 MiB) Viewed 2619 times
- Chiltern-20110610-00253.jpg (1.78 MiB) Viewed 2618 times
Next I carefully measured the distance apart and location of the remains of the old front spring hanger brackets before I ground them off the floor panel. These were the original factory brackets and have not previously been replaced.
I found the original rivets and rivet holes remaining in the rear seat crossmember rear flange and in the chassis rail sides. The front ones were there too but were still in the spring brackets the floor having rotted away around them. So the front ones are no good for reference! Incidentally the rivets are ¼” diameter with round dome heads.
In theory the rear rivet holes are good reference points for mounting the new brackets.
- Chiltern-20110611-00274.jpg (1.57 MiB) Viewed 2618 times
- Chiltern-20110611-00259.jpg (2.08 MiB) Viewed 2618 times
- Chiltern-20110610-00248.jpg (2.22 MiB) Viewed 2618 times
- Chiltern-20110610-00252.jpg (1.1 MiB) Viewed 2617 times
- Rear Jig 048.jpg (1.53 MiB) Viewed 2620 times
The pic above shows the spring hanger plate to far forward before I made adjustments the the mounting position. You can see the holes in the plate where the rivets will go.
I fitted the jig components on to the car & frame and mounted the front spring hangers…. What I found after several hours of adjustment was that if the hangers were located to the specified 25” from the centre crossmember the rivet holes in the rear seat crossmember missed the spring hanger bracket rear ends (edited) completely and the centres to the rearmost spring mounts were to great. The front of the brackets were also sitting to far forward under the passenger floor.
I ended up setting them both sides to 25 1/4”… the rivet holes were then ok and the centres to the rearmost spring shackle mounting holes were spot on. It was interesting that a small movement of the spring hanger had the effect of a larger movement to the rear shackle centres?
It’s annoying not to get it spot on the spec dimension but maybe it’s just about within manufacturers tolerances?
I drilled and bolted through the spring hanger mount on the driver’s side using the hole where the rivet was removed and double checked all the measurements.
- Chiltern-20110611-00277.jpg (1.75 MiB) Viewed 2617 times
- Chiltern-20110611-00278.jpg (1.77 MiB) Viewed 2617 times
The spring mount centres are exactly 43 3/32” apart horizontally and at the correct relative heights.
The overall width across the front spring hanger brackets was 42 1/8” and approx 38” between the inner faces. This was the same dimension as the old brackets were welded to and according to my calculations works out at 40 1/8” for the centres of the springs. This seems to agree with my measurement of the rear axle pad centres as well.
I ignored the width given in the manual over the ends of the mounting pins as it didn’t seem quite right and I didn’t know for sure what the original mounting pin thread length should be.
The next job is to drill and bolt the n/s hanger then fabricate and weld in chassis repairs behind the boxing rear extension panel.
Once that’s done I will do a final check of the relative mounting point positions and a very thorough check that its all level, then weld the spring hangers and their plates in place.
Im also going to put new rivets in to replace the old ones.
Oh and Ive also braced the 'cab back' as shown in this pic
- Chiltern-20110611-00273.jpg (1.69 MiB) Viewed 2617 times
That’s it for now
Taupe
I'm also replacing the part of the flitch panel which covers the kidney panel, but the replacement one I bought doesn't seem to be quite the right shape.
Still, I'm learning as I go along, and with your info (and following your fantastic thread!) I feel more confident to proceed. I shall start my own restoration thread soon, so you can all see how I get on.
Your impossible talent is a testament to the collective grit of the Minor community...