Part 34 - Buffers and Couplings
Most of the remaining work will be below the footplate, and, I am so keen to get on with the plumbing, we’ll start with buffers and couplings. You may well have noticed that the J65 has had both of these for a (long) while, but I will still cover them here. Ground Rules
I always fit sprung buffers, doing conversions if need be, and I like my locos to be equipped with a good representation of a proper screw coupling. That said, I did find the Exactoscale functional screw couplings were a step too far on a working loco. Perhaps perversely, I like my couplings fixed firmly to the body. A brief diversion (rant) on auto couplings
I really don’t favour the various flavours of auto couplings. The Hand Of God may offend some, but it is only an occasional intrusion, and the strange mechanical contrivances perpetrated by some auto couplers are plain to see all the time. The only ones which are themselves reasonably invisible, AJs, mean that what should be there and visible, isn’t. And frankly, the struggles many of you seem to have to go through to get them working properly, and to keep them that way, strikes me as some sort of cruel joke sent by Mr Jackson to mock the afflicted.
This is of course a personal position, and you may choose to differ. My most recent personal experience with AJs was with a couple of wagons so fitted at one end and with 3 links at the other, presumably as converter wagons. These got coupled together at the front of a heavy goods train that we put together on Tony M’s Buxton to see how heavy a train we could get various locos to drag up his 1 in 60. The AJ fitted wagons had to be removed as the strain was stretching the couplings and unbending those fiendish little hooks. But back to business.Buckjumper Buffers
Both kits came with Alan Gibson style turned brass sprung loco buffers. Slaters do something very similar. For those not familiar with these items, they have a turned brass body drilled right through to accept the shank of a bright steel turned buffer head. This shank has its tail end turned down to <0.5mm. There is a turned brass top hat shaped plug, the narrow end of which fits into the back of the buffer body, and which is drilled >0.5mm to allow the buffer shank tail to pass through. Finally, there is a tiny spring which fits over the tail and is sandwiched between the buffer head and the plug to provide the spring action.
Assembly is just a matter of soldering the plug into the back end of the buffer body, which leaves the wider end of the plug to locate the buffer in a hole in the buffer beam. The spring is slid onto the buffer shank tail (fiddly)and the whole buffer inserted into the body. To retain the buffer head in the body you have a choice. You can bend over the end of the tail where it sticks out of the plug, having checked that the buffer head is protruding the right distance out of the body. You will only get one or two goes at this, before the 0.5mm bit breaks off, so be sure to get it right and don’t expect to be able to remove and re fit them very often. Alternatively, if you are me, you cut small bits (1.5 mm long) of insulation stripped off fine insulated wire (the one I use is 0.9mm o.d.) and slide these on to the tail. They are a tight fit, and yes, that is fiddly too, but worth it, as I find that they hold firm in use. They stay where you put them and mean the buffer heads can be adjusted, removed and replaced at will. (Doing things “at will”, usually firing, was one of my school friends favourite jokes, it wasn’t funny.)The J69
I purchased the J69 kit with LNER group standard stepped body buffers as that was what was fitted to 7054 in the early 30s. These buffer bodies had square bases which should have had a bolt in each corner, but as purchased these bolts were missing. As it was clear where the bolt holes should go, they were drilled and wire pins fitted to represent the bolts. They and the plug were soldered in place using 188° solder. The completed bodies were then soldered to the buffer beam, using 145° solder so the buffer bodies stay assembled. The square bases make it easy to get the bolt detail in the right place. The J65
The J65 7155 had GER standard parallel sided, round based buffers. The GER mounted these with a wooden pad between buffer and buffer beam, which is slightly bigger than the base of the buffer body and 1.5 inches thick (on Locos, more on tenders). The Gibson buffer bodies that came with the kit didn’t attempt to reproduce the wooden pad.
I used 20 thou brass etch scrap (20 thou = 0.5mm = 1½ inches, roughly), cut into squares a bit bigger than the buffer base, drilled centrally to fit the buffer plug and assembled with solder between plug and buffer body. The corners were filed off and then the bodies mounted in the Dremel and the pad turned down with a file until it was just proud of the buffer base.
These buffers should also have had 4 visible retaining bolts. When I did them mumble mumble years ago I chickened out worried I wouldn’t be able to get them neat enough. Probably, if I did them again, I would have a go, but I’m not taking them off now. Screw Couplings
My preferred screw couplings come from Masokits. These too can be fiddly to assemble, they’re not called Masokits for nothing, but I think they are the best available. I do the whole fret of, it was 7 but as of April this year 8, pairs in one go, so one nights entertainment keeps me in couplings for a while. Mr Masokits has lots of nice assembly ideas, the one I learned from the screw coupling fret instructions was the use of clutch pencil leads to align parts with small holes while you solder them together, while leaving the hole free of solder or worse a soldered in pin.
I prefer to keep the couplings removable and both J65 and J69 have the front coupling passing through the buffer beam and then a little bracket filed up from scrap. The coupling is retained in place with a sacrificial bit of .3mm wire. Making it removable means that there is one less bit of gubbins in the way when it comes to applying the loco number. We will come back to the other plumbing items which will decorate this area shortly.
Pity you never spot the bent step until after you take the photo.
On the rear buffer beam however the amount of assorted brake system detail fitted behind it (see Part 14 The Chassis Cosmetic Details
) means that there is just no space behind the buffer beam at all and so the rear couplings are just soldered solidly in place. Fortunately, the LNER only numbered the front buffer beam.
Here endeth Buffers and Couplings. I suppose I could just have said fit Gibson sprung buffers and Masokits screw coupling, but it wouldn’t have been so much fun, and now I can no longer avoid addressing the remaining under footplate plumbing.RC 61056