of AC's post-war 2 Litre Saloon
Body Panels (and fittings)
This section excludes the main body shell and other panels that are pinned to the wood frame.
Many of the inner panels are made from mild steel, and are likely to require repair or replacement.
Spare wheel compartment panels
The spare wheel compartment features a side panel made from a single sheet of steel, bent almost into a U-shape. Its upper edge is folded over as a reinforcement. At the bottom, it has a series of flanges so that it can be bolted to the chassis underpan and the small floor panel. There are cut-outs to clear the spring shackle bolts and access holes for the spring bolts.
There is also a steel floor panel that bridges the gap between the chassis rear cross-member and the rear cross-member of the wood frame. There is a wooden batten bolted to the chassis to allow that floor panel to be screwed down. The screwheads need to be as flush as possible to allow the spare wheel to slide in without damage. Originally, there were slight gaps between the ends of this panel and the plywood boot side panels, allowing road spray and dirt to pass through. I stuck some self-adhesive foam neoprene (left over from other parts of the car) to seal those gaps. The floor has some drainage holes plus an additional hole towards the left end, close to where it meets the side panel. This is for the wiring to pass through, with a suitable rubber grommet.
Rear inner wings
The rusting away of these inner wings, speeds up the deterioration of the wood frame. Their design also acts as a water and dirt trap. Most of the lower edge is folded into a channel around the edge of the plywood boot side panel. Therefore, I did away with this folded edge, left the edge of the ply exposed, and added some extra woodscrews. The plywood had already had its edges sealed with water-proof adhesive and then painted over. To secure the inner wing to the plywood, I added some no.8 woodscrews with thick washers so that the thread would hold. This change also makes it much easier to install the inner wing, since the brake backplate normally gets in the way.
One other minor change was to the way I fixed it to the wooden wheel-arch. Orginally it was held by a large number of 3/4" nails. I used no.4 x 3/4" stainless steel woodscrews, in slightly smaller numbers. With these two changes, it will be much easier to remove these inner wings again should the need arise to make repairs to the wood or the panels.
If you need to make new replacements or extensive repairs, most of the dimensions you need can be taken from the wood frame. The photos here will show you what the finished article looks like, remembering that later ACs had a slightly different cut-out for the back axle. The extended cut-out as shown here, is to accommodate the lever-arm rear damper. For repairs to mine, I used a heavier gauge than the very thin original, increasing from 0.7mm to 1.1mm.
If, like mine, your AC had lever-arm dampers removed, that leaves a large gap where water and dirt can wreak havoc inside the rear of the car. It is a good plan to make and fit a panel to close that gap. A detachable section will allow easy access during maintenance or repair.
Additional details to note include bolt-holes for the boot floor support batten. On the left-hand inner wing, the earth-wire for the rear lights is attached with a wood screw.
This is a simple 1/4" (6mm) thick plywood panel, screwed to the various wooden battens. Mine had been cut in two, probably by AC when they upgraded my rear dampers and this makes it much easier to remove. So I made my new one in two parts. I also increased the thickness to 9mm, because I could not find suitable quality ply in 6mm, and it probably adds a little extra strength to the part of the body which lacks any bulkhead. You might want to consider making an access hatch for the fuel pipe?
Sheet aluminium is used for the panel under the rear seat, and also for the cover over the gearbox. Steel is used for the rear floor panel and so whatever paint system you prefer needs to be done as meticulously as the rest of the painted steelwork on the car. The other floor panels are plywood, 9mm thick, but only mediocre quality 5 ply material on my AC. Both steel and wood floor parts were coated in the usual bitumen. I painted the wood with aluminium-based primer and 1-part polyurethane.
The front floor panels are attached to the main panels with 2BA countersunk screws and corresponding anchor nuts rivetted to aluminium strips under the floor. The strips are bolted to the main floor panels with the same no.10 UNC screws used extensively on the AC.
Above are the front floor panels viewed from underneath, after removing the bitumen coating.
Above, you can see the brackets for securing the front seat, and the aluminium strip with 2BA anchor nuts rivetted unerneath.
Aluminium cross-member and seat frame
An aluminium cross-member helps to support the floor and rear seat. This part is fabricated from several parts held by aluminium rivets. It is attached to the chassis by small steel brackets and also to the brackets on the hinge pillars. Unfortunately, it is only possible to remove by drilling out some of the rivets at one end, to remove a small section. I refitted it held by brass BA screws and nuts for easier removal in the future.
The aluminium frame that supports the rear seat (and fuel tank) is bolted together with no.10 UNC screws and nuts. It is held very firmly with woodscrews to the rear shelf framework, but only a single small screw holds each bottom corner to the main sillboards, reinforced by a small steel plate. This had fallen off on one side of my AC. I strengthened these joints by using 2 woodscrews each side, and increasing to no.10 gauge. I plan to add seatbelt anchorage points, so building up the strength was essential.
The main weakness of the bulkhead is where the battery sits. Although there is a lead tray under the battery, it is not big enough to protect the aluminium from acid splashes. After holes appear, rain water might get through and destroy some of the sound/heat proofing inside the bulkhead. At least repairs should be straight-forward, either welding or gluing repair sections in. Most of the damage is hidden from view anyway. It is then advisable to add some protective material to protect it from further damage.
Front inner wings
These are made from steel, but a heavier gauge than the rear ones. AC's from about mid 1948 onwards, have louvres cut into them. They are bolted to the chassis with 4 no.10 UNC round-head machine screws, into threaded holes. There is a rubber seal between the panel and the chassis. Originally, the seals were solid rubber (1/8" or 3mm thick), but these failed to keep out water along this uneven stretch of chassis. Therefore, I fitted self-adhesive foam neoprene, 5mm thick.
Don't panic if you have trouble reassembling the front body panels and getting bolt holes to line up. Flexing of the radiator on is rubber mounts, and the inner wings on their rubber seals, plus flexing of the panels themselves, allows plenty of adjustment until it goes together.
These use a heavier gauge alloy than the rest of the outer bodywork, at 16 gauge (1.6mm). This combined with the compound curves gives them sufficient stiffness and strength, reinforced at the lower edges with steel cord beading. Yes, I did say "steel"! For that reason, I run oil and grease into the beading. The front wings might have cracked where the bumper irons press against them, and also near the larger mounting bolts. Some form of reinforcement along those upper bolt areas would safe-guard against damage by anyone leaning against or sitting on the front wings.
The rear wings will probably have corroded where they are in contact with the steel inner wings. When reinstalled, it is recommended that you add a seal to the inside edge, which normally acts as a water/dirt trap. Corrosion damage might also occur around the coachbolts on the wing-stays and the front end of the front stone-guards. Make sure that the new bolts and the brackets are separated from the alloy with rubber or sealant, or maybe some other synthetic washers.
Interestingly, these are made from brass, although the first few ACs were built with aluminium-alloy cowls. The only likely challenge with these is to get paint to stick, including the internal black paint. The most popular approach is to be scrupulously clean and to apply self-etching primer.
After the front hinge bracket breaks (as they nearly always do!), the bonnet louvres tend to get dented. The bonnet is made slightly flatter than the curvature of the scuttle, so that it fastens down firmly.
Made from chrome-plated brass, the fixings varied during the production years of this AC model. The windscreen and fixed side windows on my 1949 car, featured little angle brackets, screwed and soldered on. Unfortunately these were made from sheet strips bent over, which makes them prone to cracking and breaking. It might be better to make new ones out of rolled brass angle-girder, although the angle of some brackets is not quite 90 degrees. They need to allow clearance for the varnished wood trim. The rearmost brackets on my side windows had never been installed from new. I think they broke, and someone did not bother to replace them! The cut-out in the wood frame on one side was never made, which is why I'm sure of this. It will be different for later ACs with opening side windows.
The mascot is held by 3 bolts. These only need to be slackened for the mascot to slide on or off, and fine adjustments can be made to align it with the radiator grill. The mascot is hollow, so any damage might need to be punched out from inside.
At its upper end, it is fixed to the radiator cowl with a pair of 4BA round-head brass screws. These screw into floating anchor-nuts, rivetted to the cowl. These allow fine adjustment to fit the grill. The bottom end is fixed with 4BA screws and full nuts. The pivotted section (for starting-handle access) is often damaged or lost. It is attached with a steel ball joint, and a steel 4-way split-pin. Both may have rusted beyond repair.
To be continued...
For information on mechanical maintenance, see the "Maintenance" section.