Aaron's Dax De Dion build thread

[aaronjb]

I thought I'd try and start a 'build blog' post here - I'm going to have to go back and fill in the blanks of all the historical stuff I've done, but maybe I'll be more inclined to keep this up to date rather than the blog itself which, as Kevin likes to remind me, hasn't been updated in years I'll start trying to post a six-month or so chunk per post, and catch back up that way over the next few days!


Everything began in .. 2011, maybe? With me sitting in a friend's office and looking at his model Cobra; he said to me "How expensive could it be?" and we downloaded the price list for Dax .. quick calculations later suggested £25k and I'd be on the road!


I can hear you all laughing uncontrollably now.. optimistic isn't the word! But I digress. A trip to Detling (RIP) where I sat in a Dax, a GD, looked at a Viper and looked at the AK was followed by a trip to a Dax open day and a test run in their demonstrator (not a test drive!) and a trip to Crendon to meet JK and sit in a Crendon.


At the time I wanted to build a 'modern' Cobra, but over time that has turned into wanting a more period correct Cobra and I probably should have bought a Crendon - but never mind, I committed to Dax… and so the story begins. (and hopefully continues, but I seem to be plagued with Server Errors when I try to post, so we'll see!)

[aaronjb]

Early 2012 saw me road trip to deepest, darkest Wales to purchase an XJ40 donor off a man who declared "I hope you aren't going to break it for one of those kit cars, this car is too good for that!"





I can't even describe how optimistic he was! You could see daylight through the firewall, the pedal box was the only thing stopping the firewall from falling out in fact, the inner wings were completely rotten where the wiring looms passed through and so on! We ended up chopping the boot off with a plasma cutter so it would fit in the garage with the door shut, stripping it and waving goodbye to the rest - keeping the V5, of course! Amazingly, we only set light to it once with the plasma cutter..


If I were doing it again I'd just buy a donor pack... there was a lot of swearing at rusty bits, but eventually all the required parts were liberated with no thanks to:


The front suspension arms on one side, which were stuck together and eventually liberated by drilling out a bolt:



The rear disc that the previous owner had put on in the wrong orientation, so you couldn't get to the handbrake adjuster. A 3-leg puller and lump hammer got the disc off eventually:



The swing bolts were well and truly recalcitrant, too, but finally the crusty diff was liberated:



Then, there was a break of a month or so while I waited for Dax to deliver the chassis and chassis packs, and I gathered other parts....

[aaronjb]

Somewhere in here, I managed to pick up a few bits that I thought would come in useful for the build.. namely:


A fully running 390cuin Ford FE engine
A partially stripped 428cuin Ford FE engine block, crank and pistons
A pair of Edelbrock FE heads
A set of throttle bodies and EFI setup to suit
An Aston Martin fitment Tremec T-56 (long input shaft)
A QuickTime bell-housing


Some of that - one engine, the bell housing and the Tremec - were necessary because Dax didn't have any jigs to put the FE engine into their chassis. This should be your first clue that I was heading down uncharted territory! Not that I am the first person to put an FE in a Dax (although I might be the last?), but clearly they hadn't kept any jigs because who would be stupid enough to do that?! I believe their "big block Ford" option was the 460 series engines, FWIW.


Finally, in May 2012, Dax arrived with a chassis and associated chassis packs - everything that should be needed to build a rolling chassis. You can also see the two engines, one of which, plus gearbox, was just back from Dax:



It all took up a lot of space in the garage:





Not a lot happened, really; the following year was spent stripping the donor parts down to components for refurbishing, organising powder coating and/or refurb - Wards for the hubs, a local guy for blasting & powder coating the suspension arms, that kind of thing.


Stripping bits down, the front end went quite smoothly:



The rear end parts were considerably more crusty and resulted in at least one snapped bolt (apparently this is quite common, so Ed at Wards told me):



Then .. hiatus.

[aaronjb]

2016 arrives, three years after I got properly started and .. well.


The hubs came back from refurb looking shiny and new, with new bearings and so on all nicely set up (except the fronts):



I surveyed the nut & bolt kits I'd taken delivery of several years prior and found that I was missing a boat-load of bushes and a few bolts and, rather importantly, about 50% of the front suspension. That was quickly sorted via Dax, and I got all OCD and sorted stuff into boxes and piles:



I tried to strip down the front suspension arms of their bushes and found that neither my 10tonne press, nor pullers, could extract the original bushes. The hacksaw did, however:



They were then blsated, powder coated and assembled with the new bushes:



Finally I started actually assembling things to the chassis like the ball joints into the De Dion beam, using sockets & threaded rod:



I assembled the shocks & springs. Due to time in a slightly damp garage the zinc plating had started to show some rust, so they got a coat of black paint:



And my first 'Dax' foible - when you are trying to insert the upper ball joint and caster shims into the upper suspension arms, they won't fit. The trick is to lean on the wide end (the chassis end) at the same time as shoving the shims & ball joint in:

[corn plaster]

Keep the posting going.

Andy

[KugaWestie]

Finally I have shamed you into a build thread

[Bannon]

I'll enjoy following this thread - splendid!

[aaronjb]

Finally I have shamed you into a build thread

Yep .. it's basically all your fault! And the constant nagging by Kevin

I have a few days worth of posts saved up.. next one coming up!

[aaronjb]

The pace quickened.. because I had an imminent house move approaching!


March 2016 saw the front suspension basically complete:



And me dealing with rust on the chassis due to poor prep prior to powder coating (despite WaxOyling the whole thing and the driveway several years prior):



Discovering that I had the wrong diff yoke of the two kinds available - central pinion and offset pinion - which was quickly rectified by a phone call to Dax. Here, showing the wrong one:



Building up the rear suspension and then realising that I needed to drill the extra hole in the rear hub carriers.. so un-building half of it again..



The third hole needs to be added top right, here, using the mounting tube on the De Dion beam as a guide:



And that just left the driveshafts, which were being recalcitrant:



The Haynes manual described disassembly of the driveshafts as follows:


Using a suitable socket just smaller than the bearing cup on the lower side and a tube just larger than the bearing cup on the upper side, drive the half shaft down so that the bearing cup is exposed.


Now grasp the bearing cup with mole grips and wiggle it free of the half shaft.


Turn over and repeat.


That’s all great in theory but what I found was that the bearing cups were so tight in their bores that there isn’t a big enough pair of grips in the world.


On the advice of a fellow forum member we welded a long M10 bolt to the bearing cup and used that plus a large socket to draw the cup out of the half shaft loops – that works very easily once you have the welder set up so you’re not either blowing through the cup or welding it so poorly that the bolt snaps free of the weld.





And, finally, wheels were added:

[KevinW]

Yep .. it's basically all your fault! And the constant nagging by Kevin

I have a few days worth of posts saved up.. next one coming up!

You're welcome!

- but whats with the chassis rust - is that crap Dax powder coating or did you get the chassis 'bare'?

My garage is abs terrible for damp, but the powder coating on the Crendon chassis is totally resistant to rust.