10. NACA Duct, Badge, GRP Mirror Mouldings, Hubs, Door Latches, Sliding Windows.

10. NACA Duct, Badge, GRP Mirror Mouldings, Hubs, Door Latches, Sliding Windows.

There are a few more jobs that I can do on the nose section before it goes back in the barn for a while.

Ferrari's 350 CanAm had a little NACA Duct in the nose. It's a nice touch that we featured on a few cars. The easiest way to make  a NACA duct is to cut out the shape in your panel and bond one of our moulded ABS NACA ducts from below - for example Part No: #NACA1B, on the inside of the panel.  

We didn't have those ABS ducts back in the day so here's how I did it.

TOP LEFT PIC. I used one of our #NACA1B to make a paper template the size of the duct, folding it in half and trimming it to ensure it was symmetrical. I carefully measured its position and angle then taped it in place on the nose. A quick blow of grey primer leaves a perfect cutting line when the template is removed.

TOP RIGHT. A 10mm, narrow saw blade in my Multi-Tool followed the cutting line accurately leaving just a 1mm wide cut. I cut the top and both sides, leaving the short, bottom edge uncut. Then, on the inside of the panel, I ground away the area around the bottom, uncut edge until it was just the thickness of the Gel-coat and one or two layers of GRP mat left. If it's thin enough the GRP will bend in a gentle curve.

BOTTOM LEFT. Keep checking the flexibility of the cut piece as you grind away material until you can easily insert a spacer in the open end. In this instance I used an offcut of 22mm aluminium tube but you can coose your spacer thickness to make the opening as big or small as you like.

BOTTOM RIGHT. On the inside, I carefully laid-up a few layers of chopped strand mat to form the sides of the duct. The lighter coloured strips are Coremat which was part of the original lay-up of the panel to increase rigidity of the large nose area. You can see where I have ground it away  in places to reduce the thickness of the GRP.

I've filled and dressed the sides, increased the thickness of the visible opening edge and radiused all the edges to about 1 or 2mm. The scratches look worse than they actually are and will easily disappear under a little filler-primer. That'll do for now.


To Badge or not to Badge - that is the question. Back when N F Auto Development and a few other manufacturers were producing Ferrari replicas by the bucket-load there was always a lively debate to be had about the legality and moral legitimacy of putting a 'Ferrari' badge on a replica. To be fair, the same dilemma applied to owners of Cobras, GT40s, Countaches and many other marques - some of which were almost indistinguishable from the originals.

But the P4 was a little different. Ferrari only ever made four originals. None were ever on sale to the public, none were road cars and each one is worth many millions of pounds. So no one, with even minimal knowledge of the marque, would be fooled into thinking they were looking at a real P4 just because it had a 'Ferrari' badge on it. 

Us (N F Auto Development) and a couple of other manufacturers were even subject to an 'Intellectual Property' scam by a company purporting to be acting on behalf of Ferrari and asking each of us for £2000 in return for not being pursued for copyright infringement. Their 'claim' against us was for displaying a prancing horse on our demonstrator. Our 'badge' was a similar prancing horse facing the other way on a red background and was, in fact the 'Kent Invicta' logo of our home county. The company disappeared into the ether wnen we asked them for a letter of authorisation from Ferrari but as I recall, the other 'scamees' paid up.

Morally, of course I can understand the issue with 'passing-off' a replica as a real Ferrari - and historically, it has happened with 250 GTOs but it would never happen in our world. If an owner chooses to display a Ferrari badge on his or her replica that's fine with me - fill yer boots - I can see the attraction. The long flowing nose section on the P4 screams out for a badge so who am I to argue?

So, here are a couple of suitable badges for the nose of our P4 replica. One is a secondhand original  - about £130 from ebay and the other is a new, £20  'knock-off' - again from ebay. Any guesses?

The one on the left is the copy and the one on the right is the original. No prizes for guessing which one I'll use.

First step is to stick some masking tape around the target area. Then measure, measure, measure. If it's not in the right place it'll bug you for ever more. I took dimensions from the headlamp reveals to find a centre line. I scaled an online picture of a P4 nose to calculate the badge position between the nose vent and the radiator outled vent and I squared the front to back centre line from every datum around. The pencil line is the actual size of the badge. I estimated the radius of the badge corners at 3mm and drilled a 6mm hole in each corner of the rectangle, then cut the straight sides with a thin blade in my multitool. Much careful filing and trial and error later I had a hole with a radiused edge, 0.5mm bigger all round than the badge.

TOP RIGHT. I cut a rectangle of scrap GRP a couple of milimetres thick, drilled the two holes for the badge mounting studs, mounted the badge on it with two M4 nuts and bonded it on the inside of the nose with a bead of fibrefill all around the edge.

BOTTOM LEFT. With the fibrefill cured I removed the badge and made some aluminium packing pieces tofit behind the badge to bring it level with the top of the nose. More careful filling, filing and dressing gave me a neat, pleasing recess for the badge.

BOTTOM RIGHT. ... and here it is in grey filler primer. Can't wait for it to be red.

  It's probably worth taking a quick look back at our very first car, completed in 1991, at this stage. Here you can see the original, raised roof line around the mid bulkhead, the narrow roof and the full height doors - all compromises in the name of comfort and easy access for taller drivers but now corrected as you have read in previous posts. Headlamp covers, nose vents, badge, sliding windows and nose winglets too have recently been revisited in this blog.  

I discovered these old moulds, buried in a corner of our old paint shop. The two on the left are for making the wing mirror shrouds that you can see in the picture above. Top right is the mould for the shroud over the wiper arms at the base of the screen. Bottom right is a mould for an authentic-shaped, dash-top instrument cover that we made for one particular customer. They look a little tatty but with some work they'll all deliver at least one more pull.

A quick blow over with PVA mould release. I found a litre of black Gel Coat on the shelf. It looked OK so...

... all the moulds got a healthy layer of it.

Then laid-up with three layers of chopped strand mat. None of these parts are load-bearing so that should be fine.

.... and here are the parts from the moulds. Not bad considering the condition of the moulds.


A detail we picked up on as we were coming to the end of producing the cars was the sharpness of some of the body creases. The left picture is of the front wing of an original, aluminium 412P. It's quite clean and defined. The crease is there on our nose panel (right) but it's not as sharp. It feathers-off at the front a few centimetres from the headlamp reveal and again where the wing meets the scuttle. The crease starts again after the doors along the rear wings of the tail section. It's a small detail that probably no one would notice but I reckon it's worth doing on this car.


The nearside existing 'crease' is slightly better defined than the offside one. First job - rub doen the crease area with 400 grit abrasive to provide a key for the filler.

 The first application of filler - 25mm each side of the crease to a maximum depth of about 3 or 4mm on the crease line.

Patient and careful rubbing down with my long, slightly flexible MDF sanding 'Planks' eventually found the natural height and position of the crease. Frequent 'Eyeing' along the crease ensures it's straightness and my favourite trick of closing my eyes and feeling along the ridge with the palm of my hand highlights evenn the smallest imperfections in the shape.

The original, aluminium P4s all had inner wing and reinforcing panels that were riveted to the inside of the main panels. There are a few high-res pictures online that clearly show the rivet lines. Careful measuring and scaling-up from the pictures helps when marking out the hole positions on masking tape but I always check it over by eye before making any cuts or drilling any holes. ' If it looks right, then it probably is right' has worked well for me over the years.

We did this on a few of our customers cars using cut off and un-stalked 4mm aluminium dome-head pop rivets glued into 4mm holes - about 500 of them per car. The job of glueing the rivets in the holes is done after all body prep and primer work - before the final colour coat.


It's early March 2021 and it's cold and wet outside. The chassis needs a few more hours' welding and dressing to get it ready for blasting and powder-coating, then we'll need to have a big shuffle-around in our workshops. It's easy enough to lift a P4 chassis through the door, in and out of our fabrication shop but there's no way to get a rolling car out so assembly will have to continue in another building. Problem is, that building is full up with my two bikes, the stalled Berkeley T60 project, my oid Continental plus various lifts, machines and CBS manufacturing stuff. Pulling it all out, rearranging and organising needs a day or two of fine weather and a few strong young CBS staff.

So, in no particular order, I'll carry on with other jobs until the weather improves.

When I built my first P4 waaaay back in 1990, Lee Noble's selection of the 1985-6 Granada II / Scorpio as a donor for the wheel bearings and stub axles was a wise choice. Crashed cars were beginning to appear in breakers yards and plentiful availability of parts continued throughout our manufacturing years. When the time came, eight years ago, to round-up parts for this car they were still readily available so I just bought them on ebay. A previous post details my start on preparation of them and the uprights and now seemed a good time to finish the job.

I completed dressing and polishing the four aluminium uprights and assembled the bearings and stub axles in the rears. Assembly of the outer bearing shells to the front uprights was fine but when I tried fitting the inner races to the front stub axle they were too small - or the shaft diameter on the stub axles was too big !!! Sure enough - Bearing I.D. 38mm - Axle diameter 40mm. Shit - what went wrong? 

It took a while to research the evolution of the Scorpio components since we used them but it seems that the 38mm front axle diameter and taper roller bearings was a short-lived feature, lasting only for two or three years. On later vehicles the shaft diameter was increased to 40mm and a single, wide beariing was used on the fronts - they look similar, but the later versions would not fit our machined uprights. Thankfully, the rear components remained the same.

Sadly - another ten years on, the early, front stub axles are now as rare as Rocking Horse Poo. Two weeks' trawling the internet found only one in the whole of Europe. Feelers are out and the search continues for one more.

Here's an old pic of a front stub axle on the left and the two component parts of a rear, in the centre and right.

UPDATE: I joined a Scorpio Enthusiasts  Facebook group and asked if anyone had any. Eventually I found three from two suppliers and bought them all. You can see the difference in the picture below. The later, incorrect one is on the left and the '86, correct version on the right. painted and ready for assembly.

This is my 1995 'drawing' for the front uprights. Machining them on our old Colchester lathe and Bridgeport Mill, in batches of forty castings - ten sets, would take me about two weeks of deep concentration with no interruptions. I think I'd struggle to do it these days.

 Before and after. The raw aluminium front upright casting as it came to us from the foundry and the finished item ready for assembly.

Here are the finished front uprights ready to fit to the suspension.

 I reckon it's worth the effort, polishing aluminium castings, but it's a filthy job.

(Top left) Here are the two front uprights with the taper-roller bearing outer shells fitted. 

(Top right) I'm pressing the rear bearing outer shells into a rear upright.

(Bottom) The two rear uprights are almost ready to go with the inner and outer stub axle components fitted. The caliper mounting holes have yet to be drilled because we're still researching rear brake options.

I may as well tackle some jobs on the doors while I wait for warmer weather to arrive. I've already cut off the top three quarters of the window section which has to be re-shaped to he new body curvature and re-attached later on. The semi-gull-wing doors are double-skinned light-weight panels that have a single, adjustable hinge and a gas-ram to lift and hold the door in the open position. There is a chamfered hole that doubles as a 'door-pull' to close the door from indise and provide access to a 'pull cord' to release the latch as on very early Minis.

I recalled that some GRP reinforcing is required inside the door where the hinge meets the outer skin. The power of the gas rams had a tendency to slightly distort the outer skiin over time. A few extra layers of mat and resin formed into the angle inside strengthens the area. You can just see some glass strands through the round hole. Hanging the doors from a hook in the workshop roof makes the job easier.

Our customers have used many combinations of latch, lock and striker over the years but for this car, our large Bear Claw latches are a good option. Here's the plan. We won't need to lock the doors but it would be nice to have them solenoid operated with a hidden opening button inside the door air scoop. These latches have two-stage closing which complies with IVA requirements and three 9mm, through-mounting holes. Nuts, bolts and washers are an acceptable, if fiddly, fixing method, but a simple mod using slimmed-down, M6 aluminium rivnuts, pressed into the rear of each mounting hole simplifies fitting with three, countersunk M6 x 25mm screws. The threaded section of the rivnut - the first 7mm or so mut be turnd down to the I.D of the latch holes. If you don't have a lathe, just hold a short piece of M6 studding in a drill chuck, screw on the rivnut and file it down as it's rotating. The rivnut should then press into the latch and stay there tightly.

Careful measurement and gradual nibbling away with my Powerfile and a flat handfile eventually produced the perfect size opening for the striker and latch operation.

Drilling the mounting holes from the outside is a challenge too. I measured and marked the centres as accurately as I could then drilled a 3mm hole. With the latch held in position, a torch on the inside gives an indication of the direction to 'drag' and open up the holes and countersink them. I used countersunk stainless screwcups and countersunk M6 stainless screws for a strong and relatively flush fixing.

This riveted aluminium door panel was a feature on at least one of our earlier cars. It strengthens the triangular map pocket opening when it's used to close the door from inside and it gives a racy, period look. I just need to remember how I made them.


Let's start with templates. Three sheets of A3 paper folded and Sellotaped to the exact shape and size required, making best use of straight edges a few millimetres back from each rounded edge. The templates are then taped directly to a sheet of 1mm thick aluminium. We're lucky to have a guillotine to cut them accurately to the exact size but you could use a jigsaw or a nibbler.

I transferred the hole position from the template and gradually opened  up the hole with a jigsaw until it was four or five millimetres smaller than required, making an allowance for the folded edge to cover the GRP edge below. I annealed the aluminium all around the edge of the hole and with the panel Cleko'd in position on the door, dressed one edge at a time, clamping a straight edge as I worked round the hole. 

I cut two pieces of hard rubber to act as 'drifts' which will minimise damage and marking to the aluminium as I slowly dress down the edge. This is a slow job requiring a 're-anneal' or two. When the chamfered edge position has been established, the rivet positions can be marked and drilled and Clekos fitted. Rivet spacing is around 40mm, 10mm in from each edge.

We thought we'd play around with electronic door opening on this P4 because  it would ber nice not to have external release buttons.There's an ideal hiding place for a little momentary push-button switch on the inside face of the door vent - which doubles as a handle. We won't be bothering with door locks on this car as it'll never be parked-up and left in an unsafe place. So latches only.

Matt trawled ebay and found this 12 volt solenoid - a possible candidate to operate the door latches - and maybe, to release the tail latches too. This bundle of rods have been gathering dust in the workshop for twenty years. They're from an early Fiat Panda - the donor of choice for many P4 door latches. 

I stripped the solenoid and modified the plunger by silver-soldering a stainless tab with a 3mm hole for the rod, to the 'pull' end of the plunger.

Here's the first mock-up of the door latch parts, on the outside of the door panel directly above where they will eventually be mounted  on the inside. 

A brass electrical connector from an old consumer unit will allow easy adjustment of the rod length and lock the two rods together when the optimum length is sorted. If it's not strong enough I'll make a better one.

Sadly, when I connected the solenoid to a 12 volt supply it didn't have the power to operate the latch - even with no load. When the door is fitted and closed on the striker and with the added pressure of the compressed door seal all-round it'll have no chance of operating the lock.


I've made the hole for the actuating rod smaller with a pulled and ground-down M4 steel rivnut and I've drilled an extra 2mm hole in the latch opening cam, just below the the rod and fitted a short length of bowden cable with a sheath of black washer tubing. The other end of the bowden cable will be secured with a nut and bolt inside, at roughly the position shown above. This will be the door opening method for the driver and passenger from inside the car - just a simple tug downwards on the cable will actuate the latch and open the door - like on early Minis. However, we still have the option of an opening button inside the car for each door if we can find a safe place to put it.

So I had a rethink and here's version two. I've used one of our lock actuators (Part No: #ACTU1). These actuators have a geared motor inside that has much more 'pulling-power'. The actuator has quite complex internal switching for locking and unlocking all doors on a vehicle but for this application we only need two wires - the Green (+12v) and Blue (-12v) to energise the plunger into 'Pull' mode.

Success - there's plenty of power.    CHECK OUT OUR YOUTUBE CHANNEL FOR A VIDEO OF THIS

Mounting the little switch (Part No: #PBSW6M) on the inside of the door air scoop wasn't straightforward. I had to cut an access hole through the outer skin directly above the intended switch position. This 32mm hole saw not only cut out a nice plug that can be re-bonded-in later but also drilled a pilot hole for the switch.

The pilot hole was opened to 11.2mm and tapped M12 x 0.75mm - the thread of the switch. I bonded an old switch bezel with the same thread on the inside to reinforce the thread in the fibreglass. Wires soldered to the terminals run inside the door to the actuator and on to the front  of the door to exit by the hinge.


IVA requires an opening window in the doors so, waaaayy back, we developed a sliding Perspex/Acrylic panel in two machined acrylic runners. Now, the P4s door windows are double curvature mouldings that match the beautiful, flowing shape of the cockpit, so for the sliding panels to fit nicely and slide smoothly they must be moulded and cut from the same window moulds in the exact position they will be when they're mounted in the runners.

Our perspex supplier made us a batch or runner blanks 380mm long x 15mm x 8mm thick with radiused ends and polished edges. Fortunately we had half a dozen left on the shelf. Also on the shelf, in a very sad and corroded condition, was this machining jig. A quick clean-up and wire brush made it usable for one last batch. Three runners at a time are clamped in the jig which is set square and level in our milling machine vice and an 1/8" end mill cuts 6mm deep slots along the centre of each runner with a final cut making the slot a few thou' wider than the 1/8" Perspex panel. 

This drilling jig accurately places seven, 2.3mm holes along the runners (M3 tapping size), ready for mounting on the inside of the window later with M3 countersunk screws. Here, it's upside-down. The lower picture is the same jig but drilling-side-up. More later.



 That'll do for this post. Tomorrow, the final welds and dressing will be done on the chassis then it's off for blasting and powder coating. Getting excited.

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11/02/2021 16:27
01/10/2021 17:20
Thanks, I'm rebuilding a Morgan with aid of your parts, catalogue and staff explanations especially help[full
Peter Sykes