Rear Axle - Jag Rear Overhaul - Part 7

Ok, we are really making progress in the right direction now. No more stripping of parts and pulling things to bits, its all finishing and reassembly now.

In the last post you will recall I had the final base coat all prepped ready for finished colour......well here it is. These first pics are of the diff head all painted in metallic silver so it should blend nicely with all the HPC ceramic coating, polished alloy, stainless and chrome.

This is how the paint came out straight off the spray gun. Its the first time ever that I have used a spray gun as I never had the gear. I splashed out a while back though and bought a reasonable compressor and an Anest Iwata spray gun. Pretty good items I am told and I have to say I was really impressed with the finish. Totally stoked for a first attempt apart from a couple of rogue sandfly's and a bit of dust.

Next step was to give a good coat of clear which I did soon after these pics. I left the sandfly's and the other two imperfections and came back to them next day. Firstly I sanded the whole diff head with 1200 grit wet and dry and got it ready for more coats of clear, then I sanded out the wee imperfections and touched them up with my airbrush. The silver went on pretty well and matched perfectly, so all good.

Then I broke out the Iwata again and gave it a good few layers of clear. Its amazing no matter how you go about painting the diff head you still seem to miss a bit, there are so many bumps crevices and angles! Not a worry though I'll do that one spot I missed with the airbrush tomorrow, but meantime this is what it came out like with the clear all but finished.

Again this is just straight off the gun so pretty stoked! I did have a bit of drama with the clear going all cloudy though. Quickly shot upstairs and googled that and found it was a temperature thing. Just too cold and the air was damp. The cloudiness is caused by moisture. A quick shot with my hot air gun to warm everything up and the cloudiness disappeared.

I have a couple of runs I'll need to knock back with sandpaper and that one wee touch up, but apart from that its probably good enough to get the final shine using a bit of cutting polish without any need for sanding, especially given it is just a diff head. As my mate Bill says, at least the possums and all other road kill will have a nice view of the car. Very happy indeed.

Actually while I'm talking about the view for road kill.....there is a big square plate that reinforces everything under a jag rear. A lot of guys just don't bother with this but I quite liked this custom one I found and started prepping that for a bit of paint too.

Here it is being masked up. I had the metal polisher shine the flames so I will just paint the background. In this next pic I am trimming the masking tape with a sharp knife.

Heres a close up.

And here it is all primed ready for a first sanding.

Another day dawns and after a couple more coats of primer its time for some colour.

And with the masking tape removed!

Lastly I wanted to add a bit more detail and I have to thank the late Steve Foster here! I first met Steve in October 2009 when I got my white 33 Coupe on the road. Steve had not long gotten his blue one on the road too and below is a pic of that day with the two cars parked side by side.

Steve was incredibly helpful to me with parts and advice for my Coupe and he would become one of the main reasons I joined the Mid West Street Rods club. Steve was a sign writer by trade until he became ill with cancer. That didn't stop him though, he went on to live life to the full, finishing several projects and applying pin striping to many vehicles, not least of which was his own 33 Coupe. You can see the detail on the boot lid in this next pic.

I was fortunate enough to watch Steve do some pin striping on Roger and Ange's 28 Chev sedan and to be able to quiz him for a few pointers and tips along the way. Following that I purchased a pin striping kit and have had a few practice goes. My efforts pale in comparison to Steve's but its fair to say I couldn't have done it without his typically generous attitude in imparting some of his knowledge. 

My first real attempt, apart from practices on glass, was this flame work I did on my Grandsons Pedal Car for Christmas last year. I think Jayden was pretty pleased with it!

Anyway back to the diff....I used my wobbly pin striping skills once more to give the bottom plate a bit more definition. It adds a nice touch I think.

Cheers Steve!

Rear Axle - Jag Rear Overhaul - Part 6

Can you believe it, I am finally getting some shed time again. We have had a really busy life in the past 12 months with major home renovations and repairs. It sapped all our money and our time too. In fact it is still going on but is coming close to an end.

In addition to that I went mad and got involved in road cycling. That takes a bit of time too but I am much better for it, having lost a heap of weight and getting some really good health results too...... actually that was until boxing day! Yes my blood results and reduced need for medicines is all good, but I thought I'd have a crack at mountain biking while on holiday and I came off. In the process I developed another health condition! I smashed my collar bone....no not just a break I smashed it! I am suffering for it still and can't lift a whole lot which again has impacted on shed time. Coming right now though....oh and the internet shopping and parts collection activities have been carrying on so there has been a bit of prep work going on in the background.

Anyway....today I got back onto the Jag rear, namely the diff head. In my last post about the diff I was sanding and painting the head. To date I have spent 45hrs doing that. Fingers have been blistered cracked and bleeding, but it does look pretty good so far.

Before sending the head away with all the new bearings, seals, an appropriate gear set and a limited slip unit, I painted the head in lacquer as this will be a base colour for the silver top coat but it also means the porous primer is protected from the oil and grease during the assembly process.

Its not easy assembling a jag diff and getting all the clearances right so I had to take it in to Diffs R Us to be rebuilt. Even then it cost an arm and a leg as it took him 13hrs to set that up and assemble the hubs. Don't try that at home!

So here it is in all its glory!

It looks pretty good all assembled with the polished brake mounts in place too. The claws out the front will hold the handbrake calipers.

Notice the countersunk screws that hold the shiny mount plate in place. These will soon be a cause for concern!

Once the brake discs go on I won't be able to put a bolt through the brake mounting plate and through the caliper itself, in the next pic you can see the hole is partially obscured here by the edge of the disc. So to overcome that I will need to put the bolts in before putting the disk on. That is a problem too though as I can't slide the calipers on while the disc is in place. Its okay though as the calipers are a 2 piece unit I will be able to split them. Bolt one side on to the mounting plate, then slip the disk on and lastly put the other half of the caliper on.

It means it will be a pain in the backside if I ever need to remove the disc as I will need to split the caliper and bleed the brakes when I reassemble, but that is probably not going to happen very often (if ever) as the back brakes don't do a heap of work and the car wont do too many miles.

Replacing brake pads will still be easy as they come out through a slot in the back.

In this next pic you can see what it will look like once the caliper is mounted. See how it grips around the disc. This is why I can't mount the caliper then put the disc on later. If you look carefully you can see a join down the centre of the caliper where the two halves come apart. That big rectangular opening in the back face is where the brake pads can be removed and replaced.

Here is a side view with the caliper not quite in position so you can see the mount holes.

Actually thats not quite true....its because the caliper wont quite fit yet. The caliper mounting points are about 2 mm too thick so the caliper would be sitting off centre if I plowed ahead now. That would not be ideal!

You can see in this next pic how the mounting lug on the caliper overlaps the mounting plate. Its only 2mm but enough to screw things up. I will get that 2mm machined off, then we will be good to go.

As you saw earlier the mount plate runs pretty close to the brake disc so there is no room to get a bolt head down in there, so I need to use these countersunk bolts. Once I countersink the holes they will sit down almost flush with the mounting plate. Here it is before.....

....and after.....

When I bolt the caliper on I will use spring washers and a locking nut so that there is no chance of this bolt coming loose and fouling the brake disc. It wouldn't be the end of the world if it did....it would just scrape on and probably damage the disc and it would make a horrible noise.

Remember though how I said earlier that I was concerned about the countersunk screws that hold the shiny mount plate in place. While these are countersunk and out of the way, they would be a real problem if one came loose. If you look closely in this next picture you can see the studs that go through the drive flange have a head on them (see the reflection in the shiny brake mount plate) and whats more they are directly in line the countersunk brake mounting plate screws. If one of those countersunk screws came loose it would hit the drive flange stud and stop that axle turning....now imagine what would happen if that occurred at 100kph. One rear wheel locking like that would be catastrophic!

I looked at the other jag diff I have here (now remember these don't have the same clearance issues as they don't use a shiny brake mount plate like I have made for the Wilwood calipers) and I remember now....the original bolts at that point are held in place with locking tabs.

Sooooo, back to the drawing board.

I don't feel I can effectively lock the countersunk screws so I will go for a traditional bolt and use a spring washer under them. I will also drill tiny holes through the heads of the bolts and wire them together. This is overkill but I want to be really certain about this.

Here are some sample pics off the web showing the bolts with their drilled heads and below that a pic of what they look like once wired up.

Another modification will be required though as I don't have room for a bolt head and a spring washer in between the brake mount plate and the flange studs, so I will need to recess them into the brake mount plate. All will be good, just more machining and more bolts required.

Lastly, here is the head all mounted up on a stand ready for me to apply paint.

Next time we should see paint and be able to put the unit back together again!