Restoring the doors is similar to doing the main bodywork, but I would not usually recommend removal of the alloy panelling. Its edges are folded tightly over the door closure strips, including curved sections. The panel might be cracked already from the original construction, which will be disturbed when unfolding. Therefore, only remove panels if absolutely necessary, and if you possess the necessary skills (or can engage a professional with experience of Duralumin sheet). The most likely reason for removal would be deterioration of the top plywood rail, which is slightly curved.
Look at how complex the folding of the panel edge is at the top of the quarter-light.
Most deterioration will be the wood along the bottom of the door, and also just below the quarter-light window. It is relatively easy to release the panelling at the bottom, anneal its edges, and then fit new wood and reassemble. The two bottom panels can also be removed.
A slight short-coming of the wood frame construction, is that the main bottom rail is not properly fixed at its ends. That is, its ends simply butt against the front and rear pillar. It relies upon the plywood section to tie everthing together, but this plywood is likely to have deteriorated.
The bitumen coating was probably for sound-proofing.
In the above photo, I had removed bitumen from inside the panelling and most of the wood except the plywood rail. This plywood had delaminated and had been attacked by woodworm, and was beyond repair. Woodworm had also seriously attacked most of the ash rails at the bottom.
Lower wood frame repairs
The most likely candidate for renewal, is the plywood rail from the bottom of the door. Here is the old and the replacement for the left-hand door.
Here is the bottom rear corner (left-hand door) with new plywood fitted.
The photo above shows new timber being test-fitted (front/bottom corner, right-hand door). Note that when installed, this plywood will be slightly twisted and also very slightly curved. The inner rail that fixes to it, will also be very slightly curved. This needs to be considered when gluing the inner rail and plywood together so that they are not accidentally kept flat. They should be fitted to the door while the glue sets.
Water from the main window tends to collect inside the bottom corner of the door, and cause rot as seen above. I added a wedge shaped piece to help keep water in the drainage channel, as shown below.
Having removed the bitumen, I plan to add a more modern foil covered sound/heat insulation, which will also direct any rain water away from that gap between the bottom rail and the alloy panel.
You can see (above) the join between the two panels on the underside. You can also see one of the three drainage holes. Unfortunately, the panelling was punched into the holes, creating a water trap between panel and wood. It is recommended that you trim away the panel around each hole.
After removing the base of the door pocket, piles of woodworm dust was revealed! The plywood pocket base was nailed on, so I screwed the replacement on. Nails have no place in a high quality car frame!
Old and new bottom rails, complete with drainage channel and holes.
The bottom rail assembly remade, with the original door closure strips (aluminium) fitted. The strips extend across the front and rear pillars, potentially making it physically impossible to reinstall this assembly. But because I made a repair piece for the bottom of the rear pillar, it was possible to put it all together.
A major difficulty of making this new woodwork, is that you can't test fit the doors while the panels edges are unfolded. You have to test fit the frame part/assemblies, and take measurements - without making mistakes! Unless you have removed the entire door panelling, in which case the door could be test fitted. I made a large cardboard template of the doorstep and an external template of the doorstep edge, to match against the door.
Before gluing in the new wood, I annealed the panel edges. I used the sheet of aluminium shown (held behind the panel edges), to reflect the heat from the blowtorch. As with the main bodyshell, I coated the edges in plain soap, and heated the panels until the soap turned black.
A difficult problem with my right-hand door is shown below. The profile of the bottom edge did not quite match the door-step profile. The woodworm may have done me a favour, here! With renewing all the lower wood, I was able to make the new frame profile match the door-step. I bent the door closure strips accordingly. After annealing the main door panel edges, I panel-beat the panel to match the correct profile shown in the lower photo.
Above is the new woodwork under the door pocket. I added a wedge shaped piece for one of the joints, because the original screws are covered by the panel. At the top of the photo, you can see the butt-joint at the front end of the bottom rail, held together by the plywood.
Old and new door pocket bases are shown above. The arrows highlight a slight change in angle of the cut-out that I made. This was to permit base to slide into position. A tiny wedge shaped packing piece was added to fill the small gap that would have been left.
A test assembly of the bottom rails and the door-pocket base (6mm plywood).
At the rear of the door pocket, is a small (12mm thick) plywood section. It was originally held on by glue and single nail. I've used a screw and no glue. This will permit removal, since there is a cavity behind where debris can collect (or anything you happen to drop!).
The red arrow above shows where a screw goes in at an angle to secure one of the wood frame assemblies to the base. Unfortunately, the original screw (on both of my doors) was a tiny no.6 screw that only penetrated the plywood door pocket base. On both doors, it had come loose. I installed a much larger no.10 x 1.5" screw.
New timber glued into place.
The thin central pillar was originally screwed to the base rail from the outside. The alloy panelling makes it impossible to insert a screw from the outside, so I added a little block of wood as shown above. There is a space under it, for the water drainage channel.
Quarter-light wood repairs
The wood just below the quarter-light is vulnerable to deteriotation. It also has some quirks in its design. There is a corner piece on the inside that was glued on, and will probably fall off after you remove the trim. This then reveals a wedge shaped cavity filled with glue. I made a packing piece of ash to fill the void properly.
Near the rear of the quarter-light area, there is a thin top layer of timber which might have come adrift - tending to lift. The alloy panelling is pinned to it, albeit with panel-pins going down at an angle into the main timber. I re-glued mine down.
The photos below show the repairs being glued and completed. You can see the corner piece mentioned earlier. There are two small plywood packing pieces for the quart-light mechanism. The thickness will have to be adjusted by test fitting the window, leaving alowance for the rubber window seal and leathercloth trim.
I painted all the accessible woodwork with aluminium based primer and one-part polyurethane top-coat, as I did with the main body frame.
I refitted the bottom panels, smearing on clear Waxoyl to seal between wood and metal, and also dipping panel pins in the Waxoyl.
There are a few steel fittings to clean up and repaint: The diagonal strap, plus the packing plates that go under the hinge nuts. The recesses for the hinges might need attention too, both on the doors and on the main body frame. The weight of the doors causes the hinges to sink slightly on the main body, and for the doors to sink on the hinges. My doors had sunk about 1mm or so (a little over 1/32 inch). I made shims from plywood so that I could glue them into place, and thus raise the doors - raising a tiny bit higher than needed to allow for any subsequent compression of the wood/glue.
Above, you can see the original plywood packing for the door roller, under the door. Below is an underside view of the slightly damaged roller - missing its rubber tyre.
Windows and mechanisms
You can see the sheet aluminium gutter below the quarter-light.
I decided to apply epoxy-mastic paint to the quarter-light mechanism to protect it from rusting again (rather than plating it).
The detachable inner rail, has wax-proof cloth to keep oil/grease from the quarter-light mechanism, off the wood.
The window-winder mechanism was almost as good as new. Be careful that the fixing screws don't catch on the mechanism.
Above is the main drop-window with the runner refitted. There is a thin sheet of rubber between the runner and the glass. The original was firmly stuck, so I dissolved it with solvent cleaner and cut the rubber away with a craft-knife. I painted the runner with epoxy-mastic paint and ordered a sheet of 3mm thick neoprene-rubber. It is best to rough the surface of the rubber with sandpaper, otherwise the runner tends to jump off the glass.
There is a wedge shaped wooden stop for the window, with a piece of foam rubber (neoprene for my new one).
A common problem on the AC is that the metal window frame on the door, is not parallel with the side window on the main body. There is often a gap at the top corner. The channel for the window frame - in the door's rear pillar - can be chiselled out to make the window slope inwards more, towards the roof. But it can only allow for small adjustments, since it needs to be parallel with the quarter-light window too. It might be impossible to fully correct this issue. The above photo shows the channel with freshly chiselled wood evident.
Much to my surprise, it all fitted! The main window should wind up and down easily. If it is tight, it might mean that the frame is pressing against the edges of the glass. You can plane away a bit of wood at one or other end to free it up, but first check that the frame is not twisted. I'm not sure what the best grease is for the window-winder, but I used a synthetic grease containing PTFE.
Spare Wheel Door
The only work I did on the spare wheel door, was to fill gaps in joints with scraps of ash timber, and to seal the joints with glue. In the photo above, you can see that the lock hole took two attempts to get in the right place when it was originally made!
Restoration of the fittings, is fairly routine. Repainting or replating. The inside of the door was painted in the bodywork colour. The perspex cover for the numberplate is likely to need renewing. Tiny pieces of aluminium tubing are used as distance pieces between the perspex and the numberplate assembly (see below). The seal around the edge of the perspex is a rubber tube slitted along its length.
My boot lid was almost like new. The block of wood that the lock passes through, was split in two, which seems to be a routine fault on ACs. It doesn't appear to create any problems, but it might be worthwhile repairing with reinforcements either side (either wood or steel brackets).