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Panelling #1

Despite the lack of posts since Floored Pt 4 there has now been some, albeit very stop-start, progress with panelling.

Transmission tunnel side panels, the rear bulkhead panel, the passengert footwell and the floor panel are now crafted and have been riveted and bonded to the chassis. The final step of actually bonding and pulling the rivets was done over two different days, a few weeks apart. The severe downpour that unfolded just as I was popping in the last of the rivets on the first day did dampen my initial feelings of success but, thankfully, did did not actually compromise the Sikaflex 221 which I used as the PU adhesive. Apparently, I discovered afterwards, Sika will cure whilst underwater…

Rivetting back panel

Rain pic


The steel panels which I faffed about with in 2014 were no real use as templates in the end but a lot of hours went into making these panels –  in fragments spread out over the period January – October – to carry out the following steps:

i) Making cardboard templates.

ii) Marking up the 1.2mm NS4 half hard aluminium sheet I bought to make the finished product. I went for sheet with a plastic film on one side – so I can keep the ‘visible’ side of the panel as scuff free as possible whilst building. However the first panel I marked up was effectively the wrong way round – the plastic film would have been on the inside – so I had to redo it. Easy, and stupid, mistake to make.

iii) Carefully trimming them up so that they fit nicely as plain panels. Despite best efforts with the cardboard there were plenty of little tweaks to make.

iv) Carefully marking up where the chassis rails would sit against them – so I knew where to drill the holes for rivets.

v) Drilling through them twice for the rivets. First, from the ‘reverse side’  in 1.5mm to locate where the final rivet holes would go, the second time in 3.2mm through from ‘the visible side’ whilst the panel was clamped up on the chassis rails to drill the full hole required for the rivets.

vi) Drilling the ‘other’ holes I needed in the panels – in the rear bulkhead this was 4 holes to allow access to the diff bolts. A 32mm hole cutter worked well in the end – but marking up was a ‘best guess’ in practice simply angling a pen through from the rear and hoping it was held square to the diff mount holes. To position the holes for the harness bolts in the side panels this was easier – with the panel held in place with Clecos I simply wound a 7/16s bolt through from the inside to leave a mark as it started to push the panel out then centre punched and drilled.


vii) Deburring the panels – so that they would actually sit flush against the rails when pulled in tight by the rivets. And deburring the holes in the chassis rails too. I decided to fork out for a special Noga deburring tool (the RC1000) which cost £35 delivered – which allowed me to deburr inside the box section as well. I also ran a standard deburring blade round all the edges of the panels although in practice this mostly just left them smoothed but very bumpy…

viii) Degreasing and cleaning the panels in prep for the bonding. I used simple white spirit and some panel wipes I bought from a bodywork suppliers.

ix) Degreasing and cleaning, then scuffing with Scotchbrite pads, then re-degreasing and cleaning, the chassis rails. The POR15 paint I have used has a gloss finish and I thought the Sikaflex would want something to ‘grab’.

x) Appling the Sikaflex – this was especially awkward with the rear bulkhead panel as it had to be carefully slid into postion – so the sealant was squirted in from various different angles in the end – some was applied onto the box section face, some onto the panel.

xi) Rivetting. This was fairly straightforward for the bulkhead panel, once a couple of un-popped rivets were pushed into place the whole panel aligned and it was then a case of getting all the rest into place then popping them working from corner across to the opposite. The side panel was more complicated – despite using clecos when drilling the holes there was obviously more pull on the panel when rivetted. Starting at one end was OK, by the time I reached the other end some of the rivets needed persusaion to actually go into the holes. In the first step (rear bulkhead and back panel) I was left with two holes (out of 70-80 odd) that needed drilling out slightly before I could actually fit the rivet and one hole where I had just failed to drill into the chassis rail at all. In the end I just left that one…. When fitting the floor, in the second session, I had two holes which had been drilled through at 2mm but not 3.2. I just ran the 3.2 drill through these once every other rivet was in place.

xii) And the final step is now simply to wait for the Sikaflex to cure then see how much I need to clean up / trim. Some Sikaflex was squeezed out from between the panels and rails when the rivets pulled down. A week after the first session I trimmed up to allow for clean fitting of the floor etc, second time round I smoothed more of the overspill out whilst it was still wet.




Floored Pt 4

It’s been a long time since ‘Floored Pt 3‘!

Getting the floor fitted is key to getting the side panels on, hopefully before the end of the month – even if only for the sake of storing them in situ. Ease of drilling and mounting of the tunnel side panels is just a dependency – it’s easier to get access to the lowest chassis rails before the floor is fitted.

Using 3.2mm(3/16″) rivets, at 2″ (it’s marginally easier to mark out using a ruler!) spacing, means the floor needs a LOT of holes. The process goes as follows:

1 – Offer the panel up to the chassis. This was done by laying the floor panel on a pallet and lifting the chassis over – then carefully tweaking the position.

2-Mark the position of the chassis rails from above. This was done with a scriber to get an accurate marking as close as possible to the rails.

3-Lift the chassis off and flip it over (for later…)

4- Using the markings of the chassis rail edges, mark the centre-line of each rail. This was done with a thin OHP pen (could have been scribed but it gets tough on the hands to etch all the time!).

5- Mark the ‘pitch’ for the rivets – i.e. the distance between them. Received wisdom states something like 8x rivet diameter is correct spacing. However my panel will be bonded with Sikaflex 221 or U-POL Tiger Seal – both polyurethane sealants which are apparently excellent for this job – and will apparently offer far more strength than the rivets themselves. So spacing is less crucial – 2″ is easy to see on a ruler and inches are easier to divide down differently if there’s an odd length rail to space onto… Again, this was done with OHP pen.

6-Drill pilot holes in the alu sheet – I used 2mm. On a 3mm alu sheet, which seems to be a soft grade, the drill bit clogged a lot. So low rpm and clearing the swarf at least once per hole was important. I snapped 2 bits before realising this…

7-De-burr the alu sheet (so it sits cleanly on the chassis rails). Proper tools are available and I need to buy one to do inside the chassis rails. This time I first tried a large drill bit (12mm), but  found it took too much too quickly, so simply used a Stanley knife blade (like a paint scraping tool) and some wet and dry to get things mostly flat.

8-Offer the panel back up to the chassis. Did this with the chassis upside down, might have been marginally easier to align it the other way up but probably would have needed to tweak it after flipping it over to be sure anyway… Clamp the panel down as much as possible – I’m not sure whether the chassis  is slightly curved, or the panel, but there was certainly a need to pull down in some places – and this was after going over paint blobs and a couple of welds with a file to bring them to within 1mm of flush with the surrounding rails…

9-Drill! For most of the holes I ran back through the 2mm holes in the alu with a 2mm drill and drilled into the chassis rail so it was 2mm all the way through – before enlarging to 3.2mm in one pass. As I went I inserted 3.2mm cleco fixings – initially into every hole – then, once I was happy the sheet was sitting flat against the chassis rails, spacing them out more. I did insert some (unpulled!) 3.2mm rivets into the holes that didn’t have clecos in – just to be sure there was no movement. I tried to follow a pattern of drilling diagonally outwards from the centre/back of the car – but this may have been overkill. I have no idea whether the panel could actually ‘ripple’ if i’d followed another drilling pattern… I had done similar with the other panels – working from one edge of the panel towards the other evenly, rather than doinbg the corners and working towards the centre…

Work is still ongoing – marking and drilling the floor panel alone took about 3 hours. Drilling the floor panel through onto the chassis and temporarily fixing it as I went took about another 2.5 hours…






Benches, stands, ‘boxes and panels…!

So  – after a significant break in progress – i’ve realised that a daily or even weekly blog update on progress is unrealistic. But having this blog, not least as a place to dump all the useful info I need, remains a good thing. After a break in construction of about 12 months I started back on tasks that were not always directly car related – but always relevant. Updates are as follows:

1 – I have a new workshop – which is in the garage which is next to my house. This makes it much easier to pop out of an evening and just do a litlle bit of work. Fitting out the garage as a workshop has been a big task in itself – the worst job being sealing & painting the bare concrete floor. Two coats of watered down PVA (yes – like the glue you used as a child to stick paper & cardboard together) followed by 2 coats of Screwfix Floor Paint  (I went with Grey as it is a bit lighter than Red – these apparently being the only two choices for floor paint!) seems to have sorted it.

2- I have (mostly) made an engine stand – which allowed me to get some welding practice in a non-critical place! It’ll also allow me to easily wheel the engine and gearbox onto the driveway, where there is more space to work on them. The choice of Hobbyweld gas for my MIG welder proved a great one – i’ve not welded in 18 months – so a rented bottle arrangement would not have been good!

3- My chassis has come home – as has the engine, diff and gearbox. The chassis now sits on a large dolly – which means I can wheel it out of the garage onto the driveway very easily.

4- I have mostly cleaned up my gearbox – the recommendation from the chap at Wilco Motor Factors  of the cheapest engine degreaser they had proved a good one. I will need to replace the rear oil seal, find a new reversing light switch (having mangled the original one at some point when hefting the ‘box around) and work out what to do about blanking the speedo drive off – before painting the whole thing. But that aside – i’m just planning on refilling it with oil and dropping it in place.

5- I have made the rear bulkhead and transmission side panels and have almost completed drilling and trimming them ready for fixing. The alu is 1mm ‘half hard’ in a 5000 series (5251 I think) – it came in a 1250 x 2500 sheet at a cost of £42 from a local metal supplier . I bought some Silverline tin snips (left-hand, right-hand and straight ahead) but found them hard to use neatly – the trusty jigsaw with a standard metal blade in it has been much better (I actually broke the 25 year old Bosch jigsaw Dad gave me – and was amazed to find that I could still get replacement parts on-line).  The clecos I bought from Las Aerospace were finally put to good use – and are excellent. I only made one mistake – cutting the drivers side panel out with the protective film on the wrong side – but I can probably reuse that metal elsewhere – for some other smaller panels I still need to fit – and I still have enough alu left to redo the panel the right way round…. The main lesson from this job is – things certainly won’t fit straight away – the panels won’t be neat and square like the diagrams in the Book –  and welds WILL get in the way of a nice snug fit!

I’m pushing on with structural jobs because I need to get my GRP bodywork into my garage by the end of January – and the best place to put it is going to be on the car!

The ‘what rivets to attach the panels’ question is the current issue to overcome – sealed aluminium rivets in 3.2 and 4.8mm is part of the answer – but which grip range, what countersink angle and where to buy them from is all still unresolved…!

Mounts #2 – success!!

A great start to 2015 – the engine mounts are done! What my last post on the matter failed to mention was that I had fashioned the box section as best I could, tacked the mounts together – then allowed the weight of the engine to rest on the mounts. Before the excess weight sheared one of my, not so good, tack welds – the whole engine had slumped across to one side. I had no idea what i’d done wrong – but the mounts which had looked so good when they weren’t carrying any weight – didn’t look so good with a load on them…

Fast forward 3 months and the Christmas break gave a chance for my wifes cousins boyfriend (welder par excellence) to pop round and help me out. Apart from being a professional fabricator he also knows a thing or two about motor vehicles. Which meant he made fairly short work of the whole job.


Turns out that what i’d made wasn’t too far off the mark – but having two pairs of hands was important – and a second set of eyes helped make sure things were aligned well.


The result – better welds than I think i’ll ever manage – and a chassis with an engine securely mounted in it. Hurrah! Hopefully progress will continue on this vein in 2015!


Another paint day…

After all the effort of preparation to use POR15 and Blackcote (not to mention the expense) for my chassis i’ve decided to go for an alternative approach. Some ‘Fortress’ B&Q gloss paint has stood up well to the elements on my washing line pole in the garden – so now it adorns my front hubs, pedals and pedal box backplate. It went on thickly, but having carefully washed everything down with white-spirit first seems to have adhered well. Only time will tell – but it looks/feels rather hardy and was a lot less faff than POR15…

Bits and pieces

A bit more random progress:

Removed the maxi balljoints from the Sierra hubs (they cannot have been firmly attached as a couple of blows with a rubber mallet got them loose – no need for a balljoint splitter after all)…

Cleaned the surface rust off the hubs – not sure what they are made of – clearly cast but must be some sort of steel/iron alloy if they rusted…

Removed the Pinto fan, but not the hub to which it mounts. Seems I need to get a thin, offset, 32mm open ended spanner for that job…

Reassembled some more bits of the front suspension – and spent some more time faffing abut with a bit of cardboard – marking it up carefully for the day I come to chop holes in my fibreglass side panels…

I also made a bit of use of my lunch hour – using the ‘Wishlist’ function on both MachineMart and Car Builder Solutions I’ve started to build up a list of bits and pieces I need to purchase… The expense does seem to be steadily mounting up – i’ve been keeping a keen eye on the budget since I launched into this endeavour and currently seem to be heading towards an overall cost (including IVA, registration, etc, as well as the purchase of a fair amount of tools) of about £8k….!

Brakes #1

Family assistance has been called in to help with the engine mounts so, with the embarrassing reminder from a local Luego builder that I’ve had his pipe bending/flaring tools for FAR too long now, I decided to crack on with the brake lines. Thinking ahead I ordered some kunifer brake pipe from eBay (a cupro-nickel alloy, apparently more robust that copper alone – which can harden and crack over time). Using some old washing line to measure out the lengths needed for each run of pipe I crafted a couple of lengths.

It's rather nice to move from 'chassis building phase' to 'assembling running gear phase'...

It’s rather nice to move from ‘chassis building phase’ to ‘assembling running gear phase’…


I quickly realised that the pipe could actually be formed by hand (and to tighter radius than my borrowed pipe bender allowed)  and that the flaring tool I had did not seem 100% happy with the tougher kunifer (compared to the pure copper pipe I had bought over a year ago…). I will resort to forming the runs of pipe myself and then finding a local garage who can put the flares on the pipe for me…

Having looked at a couple of Austin Minis recently I'm beginning to appreciate how much space there will in the engine bay!

Having looked at a couple of Austin Minis recently I’m beginning to appreciate how much space there will in the engine bay!