The body gains its buffer beams, valences and roof panels.
... and I promise to write about something else one day
As far as I can tell the method of assembly intended by the Worsley Works kit involves two false cab floors to be soldered to the main body and a separate chassis built around a floor unit with two cutouts, presumably for motor bogies. The floor unit and the cab floors have etched holes, so I guess that the idea is that they should be bolted together. The side valences are provided with tabs to locate into slots in this floor unit. This sort of construction is clearly not going to be suitable when using a Farish or Atlas 'N' gauge chassis.
So where does that leave us? - the buffer beams and valence etchings seem to be a pretty reasonable representation of the prototype but without the etched floor from the kit there is not much to ensure correct alignment or to hold them in place with any real robustness.
I did a quick trial using one buffer beam and one side valence just to see if I was being pessimistic, but found that I was struggling with lots of unwieldy bits that didn't want to stay in the right place for soldering so it was time for a bit of a rethink.
The buffer beams are provided with four layers of overlay at each end where the buffers are mounted. I can't get a decent measurement from a drawing or photo to confirm this but 40 thou seems too thick to me and would leave the coupling hook and other things buried well underneath the nose. I therefore left two layers of overlay off.
The end of the nose is 20 thou thick and its bottom edge sits 1mm lower than the bottom edge of the body sides. I therefore filed 1mm off the top of the outermost buffer beam overlay which has the dual benefit of providing a good vertical location for the buffer beam, more joint area to solder and ensuring that the outer face of the overlay sits just 10 thou behind the outer face of the nose.
Assembling the buffer beams to the body still proved to be a pretty painful process. I wanted to use normal solder for this to give as much strength as possible, but this meant that the joints holding the various layers of the buffer beam together would come undone in the process. I only found a partial answer to this problem: I fitted the (N Brass LMS Oval) buffers to the buffer beams during assembly of the layers. This provides at least partial location for the various layers although everything is still free to rotate and separate when it gets hot again. The only answer to this was to keep trying and to remove and reassemble the buffer beam components after each failed attempt.
Holding things in place and ensuring correct alignment was also difficult. My solution (see picture) was not very elegant but it worked - I clamped the buffer beam in a pin vice and clamped this in the vice so that the beam was held horizontal. I kept a square alongside so that I could align the body by eye. Heath Robinson would be proud. I used plenty of flux and plenty of solder on the tip of the iron to try to get heat into the joint as quickly as possible. I think that both ends took three attempts before I was happy with them.
Ideally I would have liked to leave the buffers off until later in the assembly. This would have given me better access for tidying up the valence corners and detailing the ends but it was not to be.
Class 22s seem to have had a habit of losing parts of their valences in later life. The remaining valences could also be pretty wonky. Checking the photos of the real D6309 showed that it had a complete set of valences on one side which appeared to fit reasonably well. On the other side it was missing the centre valence and the remaining valences were sticking out noticeably.
Oops - Forgot to mention in the original post that before fitting the valences I filed a slight radius onto the bottom of the loco sides as per the prototype.
For the side with the complete set of valences I just used the etch provided in the kit after creating a couple of slight bends where the cab side sheets start to taper inwards. I found that by adjusting these bends I could just about get it to stay in place although there is very little overlap with the buffer beams. I then held one corner in place with blu-tack while I soldered the corner at the other end. After soldering the remaining corner I tacked the valence on to the bottom of the sides at several points along its length before cleaning up the solder that had crept into visible areas.
On the other side I cut some strips of 5 thou nickel silver to represent the sticking out valences. These were made so that they had a decent overlap to solder inside the body but still stayed below the louvres. Fixing these involved some trial and error before the alignment was good enough, but there weren't any major problems.
Finally I held my breath and cut the remaining side valence etch so that just the bits under the cabs could be fitted to the loco. These were then lined up and soldered in place, starting at the buffer beam end. There is practically no overlap to hold these in place so once they were tacked in place I added a small strengthening strip of 5 thou nickel silver behind the valences and sides just inboard of the cab doors.
Fixing the Roof
This was another nerve-wracking process but it went quite smoothly in the end.
I held the overlay in place with a blob of blu-tack at each end and after carefully checking the alignment I drew around it with a CD marker pen. The body and overlay were then cleaned, fluxed and tinned all of the way around the edge of the overlay. After cleaning up any thick bits of solder, the overlay was then put back into place, held with blu-tack and checked again (twice) for alignment.
Once the alignment was OK, I sweated two corners on the same side into place. I found that getting enough heat into the joint was tricky. The technique that I used was to run flux into the joint, paint flux onto the outside of the overlay and then put some solder onto the bit of the iron and immediately wipe it off on the sponge. This leaves a tiny residue of fresh solder on the bit which (with the help of the flux) is enough to transfer the heat into the joint without leaving a big unsightly blob afterwards. I pressed the overlay down using a small piece of card to (partially) insulate my finger. I still found that my finger got pretty hot though.
Having done the first two corners and re-checked the alignment, I removed the blu-tack and made the joints in the centre of the cab roofs before doing the last two corners. Hopefully this sequence of doing things helped to avoid creating any wrinkles. Finally I sweated the two sides down, starting in the middle and then filling in the gaps.
Once this was done I cleaned up any excess solder and then soldered the boiler vent and engine room panels into place in a similar way. I had made a new boiler vent panel because D6309 doesn't have this plated over.
The pictures below show the current state of play, albeit spoiled by the flash bouncing off the bare metal - it looks a lot better in real life. Note the China Clay wagon pressed into service to hold all of the fiddly bits that aren't yet on the loco. The loco has also gained some finescale wheelsets temporarily stolen from my Atlas GP7 while its own wheels get sent off to the 2mm Association wheel turning service.
There is still a lot more to do - I'm currently working through a list of jobs that I need to complete before D6309 goes into the paint shop. Most of these are pretty mundane but necessary things like making a proper fixing between the body and the chassis.