Quite a long session coming up this time. I have advanced the chassis to the point where the castings can be added but before proceeding a few points to address.
Firstly, thanks Morgan. Your explanation certainly explains why the guitar wire is so easy to solder. You caused me a little concern though, as I feared that where I had used the flux on stainless steel in the past, there might, by now, have been an adverse reaction. I have used the flux to solder bearings into the original spring carriers produced in stainless steel by Masokits, and to strengthen the fold line. I had to dig into the box of wagons that I had packed away when I moved from London (some 8 years ago!) in order to find a few that had been fitted with the original springing units. I was genuinely surprised to find that they looked as good as new, there had been no reaction of any kind and none of the bearings had come adrift. I took the following just to double check and gave the wire shown a good tug at either end just to test the joint. It does all seem fine.

Secondly, Andy W asked why I use parallel bearings. I first used them just to try them out. I found that it was a little easier to eliminate sideplay on the axle but, most of all, I rather liked the way the vehicle ran. At the DRAG-organised AGM a few years ago, I ran a rake of wagons, all fitted with these bearings, and felt that they moved prototypically. All this is only my opinion, of course, and whilst I would recommend them to anyone interested in giving them a go, it is a matter of personal choice at the end of the day.
Lastly, it has been put to me that it makes for a lot less cleaning up if one solders the bearing in place whilst the etched carrier is still attached to the fret. This certainly has merit and I will look to try it out next time. It was suggested that I put the bearing in place in the etch, flux the joint and touch the iron to the etch at the base of the bearing, allowing the solder to find its way around the rest of the bearing. Like I say, sound advice. Just try not to get any solder on the rear face of the carrier as it may hinder the operation of the springing in the W-Iron slot. It shouldn't really happen, but there's always Sod's Law.
So, to business. Next up are the wagon tie bars, which in this instance involves four individual ones, rather that the type that connect between the W-Irons on each side. I find it easier to pass the 0.3mm. wire through the holes at the base of each W-Iron, all the way across and through the hole in the opposite one. I then reach for the fag papers and thread each wire through a small piece, which is folded over each W-Iron and the wire threaded through the other side as well. Its not really necessary to thread the wire through the paper on either side of the W-Iron, that's just belt and braces on my part and its pretty fiddly as well. Threading it through the outer face would suffice. The following photo shows how things are set up and probably explain it a whole lot better than I can.

Next, fit the individual tie bars in place over the wires, hard against the fag paper and W-Iron. When soldering in place, I hold them with tweezers. Before soldering however, brush some light oil, such as clock oil, onto the fag paper, ensuring the the area around where you are going to solder has a good covering. The next photo shows how this looks.
The next photo shows how things should look after soldering the tie bars in place, removing the oiled paper, folding the ends around the W-Irons and cutting the wires. I have found it easier to fold the outer ends of the tie bar around the W-Iron after soldering to the wires, contrary to the instructions. You can run into fitting problems if you make the folds too tight. Folding afterwards makes life easier.
The next one shows how the finished job looks. I leave the wires longer than they need to be for now as it allows better handling when cleaning up after soldering. The wires need to be cut short on the outside. Leave them a little proud and file down to replicate the securing bolts.
I feel that there are really only two awkward areas to be overcome with this chassis and one comes next, the brakes themselves. As long as you take your time, go carefully and follow the instructions though, you'll be fine. The next photo shows the brakes on the fret. You will notice the letter M on the fret. This indicates which brake fret to use on the clutch side of Morton brakes, but in this case, there are only two brake shoes, which will go on this side of the wagon.
The next shot shows one side of the brake arrangement, removed from the fret, with various holes drilled out 0.3mm., into which wire will be soldered to represent the various bolts.
This now needs to be folded up and I have chosen to show each fold with its own photograph as it makes everything much clearer than any description from myself. Firstly, the outer brake shoes are folded over on to the main etch, like so.
There now come three folds, two on the inside of the fold line and one, the last one, with the fold on the outside of the line. Here's the first one.
And the second.
And the last one.
You should now have the brake shoe in four layers and the holes you drilled earlier should pretty much align, if you have got it right. Pass a length of 0.3mm. wire through these holes and squeeze the layers together in a pair of tweezers and solder them together. Solder the wire in place, cut it back on either side and file the ends down a little to represent the bolts. Also run some solder into the "foot" of the etch to strengthen it up a bit. File the brake shoes a little to get rid of the layered look and then it should look something like this.

The other end is simply a repeat job. Next job is to make up the tumbler that connects the two brake frets together and through which the operating shaft passes. For this job, its back to the block of wood. Firstly, drill out the holes in the tumbler 0.3mm. Now place the etch face down and drill through the holes in the etch and into the block of wood. Don't let the etch move and place two wire pins through the etch and into the holes in the wood. Remove one of the other tumbler etches and place it over the two pins and down onto the other part. Solder the layers together and the wire pins in place. This is how it looks, prior to adding the second layer and again, explains it better than me.
This is how the finished item should look.
We now have to solder the brake assembly into the chassis. Each assembly is soldered in place and then the tumbler is worked into position. This shows the first brake shoe assembly soldered in place.
There are two slots in the chassis into which the tab on the brake shoe assembly goes. The outer slot is for P4 models and the inner for EM and, I think, OO. This slightly out of focus shot hopefully shows what I mean.
This shot shows both shoe assemblies in place.
The next photo shows the tumbler in place on the lower brake rods. The inner and outer parts are pushed apart and the wire pivots on the tumbler are worked into the pre-drilled holes and the inner and outer parts pushed back together.
Its slightly more fiddly to put the tumbler in place on the other assembly but, once in place, the whole assembly can be tweaked so that the hole in the tumbler more or less aligns with the hole in the V-hanger. At this point, I place the brake shaft in position as this ensures the afore-mentioned alignment. All can now be safely soldered in place and this photo shows it.
To finish off the brake assembly, the safety loops need to be fitted. This is easier to do in two stages. This shows the first stage.
And this one shows the second stage with the last fold finished off and soldered in place.
The final job for this session is the fitting of the coupling pockets. I cut the end of a cocktail stick to a rectangular shape, such that the etched pocket sits over it and the stick is then used to hold the pocket in place whilst it is soldered. This photo shows what I mean and the second one shows how it is used.
Next up, I shall fettle up the castings for the axleboxes and springs and once fitted, move on to the brake lever guards and the levers themselves. I might even get the buffers on but don't hold your breath. In any case, we're almost there.