Itâ€™s been a while since my last posting in which I was having a fairly trying time persuading the Atlas chassis to look like a model of something that has been made in Glasgow rather than the U.S. The news is rather better now, Iâ€™ve been gradually ticking things off my list of jobs and the loco is now stripped down and ready to go to the paint shop.
A few more detailsâ€¦
You may remember from my previous posting that I hadnâ€™t been able to get hold of the Worsley Works bogie overlays so I was modifying the Atlas ones to look like the class 22 bogies. I used a burr, files and scrapers to delete the American detail that I didnâ€™t want â€“ the brake cylinders, brake shoes, brake linkages and the â€˜Uâ€™ shaped hanger around the leaf springs. The leaf springs were reduced from four springs in width to two and the top edge of the bogie filed to the much simpler profile of the NBL bogie. The ends of the bogies were extended with lumps of 30 thou plastikard. I eventually found that Super Glu gel seems to form a reasonable bond with the plastic of the bogie frames and could also be used to fill the small â€˜Vâ€™ shaped recesses that were left over in the top edge of the bogie after the brake cylinders had been filed away.
I stuck with the 30 thou plastikard overlays Super Glued to the bogie inner frames and ends. To this I attached a crossmember made from thin black plastikard with the inside filled with a big lump of 80 thou plastikard. I found it quite difficult to align these accurately when attaching them to the bogies and they looked a real mess when the loco was assembled. I wound up slicing them off again, reassembling the bogies, putting them onto the track and then using a piece of 60 thou plastikard as a gauge underneath the crossmember to get the height consistent.
Last time I also mentioned some problems with access to the body securing screws. This was quite easily solved. Once the crossmembers were fully dry and the coupling â€˜tonguesâ€™ attached on top, I drilled and filed a big hole through the lot to allow the screw to pass through.
The trickiest part of all proved to be the two coil springs and I tried four different ways to do this before finding a way that looked right, didnâ€™t interfere with the working of the bogie and would actually stay attached when subjected to normal handling. The big problem here is that there is very little room available because the pinpoint pickup bar is in contact with the rear of the sideframe. One (bad) idea that I tried was to solder the springs to the pickup bar. This would have worked really well except that it made the bogie impossible to assemble.
The solution I eventually found involves a specially shaped piece of 20 thou black plastikard that sits on the centre stretcher of the bogie and has two â€˜earsâ€™ that stick out under the sideframes to represent the pad at the bottom of the spring. The springs are coils of 5 amp fuse wire stuck on top of this with another piece of fuse wire up the middle to represent the spring spindle.
Finally the outer ends of the bogies were detailed with the addition of some 5 thou strips to represent the top and bottom of the channel sections and some plastikard rod to represent the cylinders on the ends of the bogies. The bogies should really have the same detail at the inner ends too but there doesnâ€™t seem to be enough room for this between the bogies and the tanks, so I had to leave this detail off. Iâ€™m not quite sure why this clearance disappeared â€“ the bogie wheelbase and centres are about right, the tanks are right and I donâ€™t think the bogies are too long, but there isnâ€™t room for this detail.
Naturally enough, once Iâ€™d finished the bogies the etched sideframes arrived from Worsley Works. I wonâ€™t now be using these, but I may build another class 22 one day so will save the sideframes for that. For anyone contemplating the same kit, Iâ€™ve included a photo of the sideframes so that you can see what you get.
As I said last time, I filed the inner (metal) tanks from the Atlas chassis to form the shape of the class 22 water tanks. I also drilled the top corner to take a piece of brass wire to represent one of the big pipes attached to the tank. This pipe will is visible through the gap left by the missing valence on D6309. The Atlas tanks are not deep enough so a couple of pieces of 30 thou black plastikard were cut to size, scribed and bent to represent the angled bottom of the tank. This was attached with epoxy, filed to fit and then tidied up with Milliput.
There is also a visible downwards extension of the chassis members in the area of the water tanks, so these were added using plastikard.
The other prominent feature in photos of class 22s are the footsteps that stick out from the bottom of the loco underneath the buffers. The design of these seems to have changed during the short life of the class with a fairly simple design being used originally. My loco is modelled as at circa 1969 so it has the later pattern steps where the lower step was shorter and set further back using a more angled design of bracket. Judging by the number of photos of class 22s with damaged corners, I'm thinking that they perhaps had regular problems with clearances related to the long overhang of the body beyond the bogies.
By adopting a slightly simpler design than the prototype, the footsteps turned out to surprisingly easy (if slightly laborious) to make. I used a piece of 10 thou brass (one of Allen's freebies again) and soldered two bent strips of 5 thou by 40 thou nickel silver strip on edge to it. Once I was happy with the position of these I filed away most of the 10 thou backing sheet so that there was just enough left to give some strength to the steps plus a tag at the top that could be bent over to attach to the loco. It's easier to do than to describe. I hope the photo will make this clear. The footsteps were Superglued to the plastiard cab floor and adjusted to achieve the correct alignment.