Aaron's Dax De Dion build thread

[aaronjb]

May & June saw some travel, so little other progress, but I did start on the fuel filler - another “easy job” on my to-do list. First, I punched a hole in the side of the boot to get the flexible filler hose out:



I have several pieces of advice here. First, I bought just about every kind of fuel filler hose CBS sell and only one is actually flexible enough (the one shown here) - it is their “ultra flexible fuel filler hose”. It is not marked externally so you will need the certificate of use that they supply with it come IVA time, so keep that safe!


Secondly, don’t do this at all. Take the tank, assuming you bought a Dax one, and have it modified with the fuel filler neck on the side and add a vent for filling. So, out the tank came and I drew all this on the side of it:



Then I took it to Ollie at [url=https://bicesterheritage.co.uk/specialists/olliminium/]Olliminium[/ur] in Bicester Heritage for the modifications to be made; he did a fantastic job of following my scrawls and also switched the fuel outlet from a straight tube to an AN-8 fitting for me, chopped the original filler off and welded a cover in, and all for an excellent price.


I also took an entire car load of engine parts over to my engine builder and left everything there for the 428 to be turned into a 462 stroker..


When the tank came back - and we are in August now - I gave it a coat of black Plastidip; that rubberised peel-off paint. It dries flat black, rather than shiny:



I also picked up and wired in a Toad immobiliser - no pictures of that, but I did manage to snap a tap trying to put a cable tie base in, which meant I had to take the steering column out again, grr.


Based on a post here, I picked up a relay that is actually a GPS tracker, too:



Make no mistake - the Chinese will know where your car is and the security on these things is laughable; a recent investigation concluded that they mostly send all the GPS info back over clear-text HTTP with no security, but .. you get what you pay for (and I’m willing to bet that some expensive solutions do exactly the same thing, too!): https://www.techradar.com/uk/news/po...security-flaws


For less than £20, though? A technological marvel.


And oh my goodness we are almost up to date now! I’ll start breaking the posts down into single jobs

[aaronjb]

I refitted the fuel tank having modified the straps a little to make the job easier (still a two man job, though!) and bought some more extra-flexible filler hose because I cut the last one a smidge short (whoops).



I also added the 1/2" vent hose using ultra flexible breather hose (CBS) and a 90 degree joint; that should miss the tyre but if not I can shorten it a little. The 1/2" vent (and 6mm breather) are both fitted to the filler tube using Revotec self sealing fittings (https://www.revotec.com/acatalog/Sel...d-Fitting.html). Hopefully the larger breather will help a little bit with spit-back during filling, but we’ll see.


The smaller breather hose runs, per the build manual, up to the highest point available (the top of the boot) and then runs across the car to the far side and was originally going to run back down to below the level of the tank; that ensures that even if the car is upside-down, the tank doesn’t empty via the breather. Instead, I fitted a small Mocal fuel tank breather valve in the (near-side) wheel arch - https://www.demon-tweeks.com/uk/moca...r-valve-23340/. Those valves are expensive, but seemed better than having a breather tube dangling under the car!

[aaronjb]

We are up to individual jobs now, hurrah, and we’re almost caught up with real time! In September, my front & rear bumpers arrived from Europa. I bought these because I wanted a way to attach rear fog & reverse lamps that was non intrusive, and because quickjacks won’t pass the IVA. I think the ultimate plan will be to french fog & reverse lamps into the rear valance, and I have a slimline LED unit for that but again, since I don’t know for sure it is IVA compliant, I’ll go with the big plastic gonks for now!


They should end up somewhere like this:



One thing I have discovered while fitting the rear bumper is that the holes on my quickjacks (from Andrzej) are slightly closer together than the tubes on the Europa bumpers. The quickjacks match the pre-made holes in the Dax chassis (thanks, Andrzej!) but the Europa bumpers do not.. Maybe the Dax ones do, I don’t know - I’ll be honest, I assumed they were all the same thing from the same ultimate supplier (Brasscraft?) but maybe not.


What that means is I’ve that had to compromise a little bit at the rear - there’s a thread about it somewhere - and the holes in the body are a bit bigger than they need to be in order to allow the grommets (also Europa) to ‘flex’ a bit and have a little wobble in the hole such that both options will fit, ultimately. I also found that the bumper should be higher than you think, and actually higher still than you can make it on the Dax, so that posed a challenge because the fixings then protrude through the boot floor!


On a real car, the bumper should be high enough to make access to the boot latch a pain in the neck, I believe, but on the Dax it is just a little higher than the bottom edge of the boot:



What you can’t see in that picture is the amount of squeezing and wiggling required to get the threaded bar to go through the combination of the holes in the chassis, holes in the body, tubes of the bumper and finally into the overriders! Strong fingers are required.. Not to mention an array of nuts that you can use to wind the threaded rod into the overriders, because you can’t just put the threaded rod into the overriders and then slide the whole lot onto the car, like you can at the front.


Here you can pretty much see that the upper fixing is pretty much directly in line with the boot floor at the rear end (because the boot floor droops down):



That meant I needed cover plates to cover the holes - first, I tried mocking plates up in cardboard:



But in the end I decided to just make the cover plates in glass using the boot floor as a mould. First, I laid a layer of mould release tape over the hole, then I used a short length of 38mm PVC waste pipe, slit on an angle, to make a tapered ‘hump’ and taped that down to the existing layer of tape, making sure that the tape extended well onto the boot floor and the vertical rear surface of the boot - and finally I glassed over the lot with a few layers of 350gsm mat:




They were then released, trimmed and can be pop-riveted back into the boot with a sealing strip. Fairly easy to remove when/if the fixings need access, and relatively watertight.

[aaannnd]

I think the problem with rear bumper is here:



but my litlle fingers was strong enough to fit it together

[aaronjb]

You might be right there - the tubes on the bumpers are definitely not perpendicular.. once installed, mine went from like yours to the even worse as they are being squeezed at the inner end, so I am probably using banana shaped threaded rod at this point Still, the main thing is that I have fog & reverse lamps for the IVA and no sharp edges, and I know your quickjacks would fit perfectly later.

Seems I never took any pictures of fitting your side vents, which is a shame - I thinned the 'lip' of the fibreglass down as much as I could to try and mimic a aluminium car, bolted the vents to aluminium angle using the included holes, then mounted the aluminium angle to the car using bonded-on studs and springs to provide a little bounce should I find them with my knee/elbow/head while working on the car.

[KevinW]

think you'll need to re-secure those reflectors - the test sphere could bat them out the way at the wrong angle.
Just need a long P clip up from thee bottom rail to ensure they can be moved.

[aaronjb]

think you'll need to re-secure those reflectors - the test sphere could bat them out the way at the wrong angle.
Just need a long P clip up from thee bottom rail to ensure they can be moved.

You could 'flex' the P clip, but not spin them round - I think the tester would have snapped the bonded in fixing out of the reflector before that (and then I'd have had to beat him to death with his own test sphere for breaking my car, obviously).. but they're no longer mounted like that :thumb: More on that in a later post when I catch up with reality

The front bumpers were waaayyy easier to fit than the rears and took about five steps..


Step one, I hung the bumper on the car using some clamps, and used very short lengths of stud to mark where the holes in the body needed to be. Then I just drilled through the body and, finally, through the chassis plates:




Then I took my Finishline grommets and visually laid them over the existing holes, drew round the outside with a Sharpie and then drew a line ~3mm smaller for the cut-out and used tiny drum and flapper sanders on the Dremel to enlarge the holes. A few trial fits for each grommet were required and then a little tweaking as things tend to ‘walk’ one way or the other with cumulative errors, but they were all fitted pretty quickly:



Finally I cut some 15mm OD stainless tube (roughly 100mm long - I think there’s 5mm difference between top & bottom to account for the rake) which is a (very) snug fit in the grommets and installed the whole thing:



I still need to get back to mounting the fog lamp etc on the rear bumper..

[aaronjb]

Progress was interrupted a little by some dog sitting:


Working on the other half's MINI (timing chain and valve stem seals):


(Note creative use of some old Ford FE pushrods as TDC indicators..)

I (re)fitted the bonnet after moving the hinge upward slightly so that the leading edge clears the bodywork, then fitted the bonnet gas struts - I bought the fitting kit from Dax and the struts from SGS Engineering and it was a fairly simple, if slightly fiddly job, with the lower fittings bolted through the bonnet opening lip and the upper fittings riveted to the 'rib' that runs around the outside of the bonnet per the instructions. Also per the instructions I made up small stainless steel 'supports' that go from the lower pivot bolt to the inner arches to stop the bonnet opening from being flexed an alarming amount by the force exerted by the gas struts! No pictures of that right now because, apparently, I didn't take any..

I also broke out the welder, which turned out to be a joy to use with a new welding mask from R-Tech and some new gas from Hobbyweld, and made up some crucifix shaped brackets for the fog/reverse and rear reflectors to satisfy the IVA man..

My welding has improved a great deal, it seems:


These sit between the rear overriders and the bumper tubes - just like the Dax reflector brackets would (I have a set of those, too, but the spacing is wrong for the overriders..):


3mm strap steel, so there is a little 'bounce' on the fog/reverse lamp but unless you certainly aren't bending them without excessive force (I know, because I put a 'dog leg' kink into the brackets to sit the fog & reverse further back, and that took a lot of force in the big vice!)

Right now, I'm working on fitting the roll hoops so I can get the seat belts in. I bought escutcheons from Europa and hoops from Dax (actually, I have a set of Europa hoops, too - they're chrome, the Dax ones are stainless) and to get the escutcheons to sit flat you have to open the bodywork up quite a bit and then 'chamfer' it so that the rubber grommet can sit down 'under' the surface of the fibreglass. In doing so, I accidentally opened up between two layers of fibreglass (probably where the inner tub is bonded in) and since I didn't want water to get in there, I bodged some Würth in:


The rear fixing goes into a 'tower' that is triangulated into the chassis in the boot, and per the build manual you should make up a metal spacer that is the same thickness as the fibreglass to avoid the 'glass being crushed when you bolt the belt down.. so I did that on the lathe and made up a little spacer out of aluminium. Simple op as I already had stock ~16mm dia, drill the centre out to 11.5mm to clear the 7/6" bolt (I know, I'm mixing my measures!) and then part it off at the right thickness. ~6.8mm for the pax side gives a finish about 0.5mm proud which seems good:



The drivers' side is, naturally, a different thickness.. so I'm glad I didn't knock up two spacers at the same time!

Once the hoops are back in again and bolted down, I need to drill through one leg each side and fit a retaining bolt. That should be a fun task inside the wheel well! But you can't (reliably) do it earlier as you don't know the final height of the hoops until the body is on..

I'm also not quite decided on how to fix the escutcheons down. There is bugger all 'meat' between the fixing points and the, now chamfered, hole.. rubber rivnuts (rubnuts) maybe? Or stainless self tappers into the fibreglass?

[Bigblock]

Progress was interrupted a little by some dog sitting:


Working on the other half's MINI (timing chain and valve stem seals):


(Note creative use of some old Ford FE pushrods as TDC indicators..)

I (re)fitted the bonnet after moving the hinge upward slightly so that the leading edge clears the bodywork, then fitted the bonnet gas struts - I bought the fitting kit from Dax and the struts from SGS Engineering and it was a fairly simple, if slightly fiddly job, with the lower fittings bolted through the bonnet opening lip and the upper fittings riveted to the 'rib' that runs around the outside of the bonnet per the instructions. Also per the instructions I made up small stainless steel 'supports' that go from the lower pivot bolt to the inner arches to stop the bonnet opening from being flexed an alarming amount by the force exerted by the gas struts! No pictures of that right now because, apparently, I didn't take any..

I also broke out the welder, which turned out to be a joy to use with a new welding mask from R-Tech and some new gas from Hobbyweld, and made up some crucifix shaped brackets for the fog/reverse and rear reflectors to satisfy the IVA man..

My welding has improved a great deal, it seems:


These sit between the rear overriders and the bumper tubes - just like the Dax reflector brackets would (I have a set of those, too, but the spacing is wrong for the overriders..):


3mm strap steel, so there is a little 'bounce' on the fog/reverse lamp but unless you certainly aren't bending them without excessive force (I know, because I put a 'dog leg' kink into the brackets to sit the fog & reverse further back, and that took a lot of force in the big vice!)

Right now, I'm working on fitting the roll hoops so I can get the seat belts in. I bought escutcheons from Europa and hoops from Dax (actually, I have a set of Europa hoops, too - they're chrome, the Dax ones are stainless) and to get the escutcheons to sit flat you have to open the bodywork up quite a bit and then 'chamfer' it so that the rubber grommet can sit down 'under' the surface of the fibreglass. In doing so, I accidentally opened up between two layers of fibreglass (probably where the inner tub is bonded in) and since I didn't want water to get in there, I bodged some Würth in:


The rear fixing goes into a 'tower' that is triangulated into the chassis in the boot, and per the build manual you should make up a metal spacer that is the same thickness as the fibreglass to avoid the 'glass being crushed when you bolt the belt down.. so I did that on the lathe and made up a little spacer out of aluminium. Simple op as I already had stock ~16mm dia, drill the centre out to 11.5mm to clear the 7/6" bolt (I know, I'm mixing my measures!) and then part it off at the right thickness. ~6.8mm for the pax side gives a finish about 0.5mm proud which seems good:



The drivers' side is, naturally, a different thickness.. so I'm glad I didn't knock up two spacers at the same time!

Once the hoops are back in again and bolted down, I need to drill through one leg each side and fit a retaining bolt. That should be a fun task inside the wheel well! But you can't (reliably) do it earlier as you don't know the final height of the hoops until the body is on..

I'm also not quite decided on how to fix the escutcheons down. There is bugger all 'meat' between the fixing points and the, now chamfered, hole.. rubber rivnuts (rubnuts) maybe? Or stainless self tappers into the fibreglass?

Hi Aaron, not wishing to make extra work for you, you might want to not fix those spacers for the seat belts yet. Any paint job will add extra material in this area, then I would suggest the spacers will need to be a bit longer to save crushing the new paint with either a seat belt fixing or bolt etc. I'm not sure of the standard of the new Dax bodies but I know from experience painting quite a few of these there was a fair bit of work and material in this area to get a nice uniform shape, and if you are doing a dark paint finish then they will require a damm great deal of work to get a uniform curve and finish in this area.

Just a thought

David

[aaronjb]

Probably right there, David - the spacer is slightly proud (about 0.5mm) but who knows what that area will look like after paint; ditto the fixing for the roll hoop through the upright, I suppose. I wasn't going to bond the spacer in, though, just let it float and be trapped by the roll hoop leg and the bolt, so I can always knock another one up

I don't think the standard of the bodies improved too much over the years