Bachmann WD Austerity
Another loco aimed mainly at our extended "Little Histon" layout, to add to our early crest BR period rolling stock operating through the station area.
Olivia's photo of 90441
WD Austerity 2-8-0 locomotive use:
Judging from all the inputs we have received, these locomotives were the primary motive power used for the long coal trains that still regularly travelled through Histon Station several times a day during the 1950s. However, the outside appearance of these locomotives reflected the run down state of the post war railways. A clean and pristine WD would have been a very rare beast indeed!
A bit of concern straight out of the box:
As received, the locomotive brake linkage was in place but only partially attached. The rear body fixing screw was in place but completely undone. The centre and front body fixing screws were completely absent. And I believe that a small moulding between the rear of the brake linkage and the cab underside was missing. I came close to starting replacement negotiations with Olivias, but as the loco functioned reasonably well under DC control, I had a replacement body fixing screw and the brake linkage could be cosmetically dealt with........ also in addition to the hassle of returning the loco, the remaining task would be more tank construction......Aghhhh! So I decided to fix the shortcomings and continue.
The cast upper body shell separated from the chassis very easily when I discovered that the screws were missing or undone, so having verified everything appeared to be in working order, I lubricated the worm gear and the driving chain gears and removed the DC operation capacitors and coils, before re-assembling the problem parts.
Likely DCC sound configuration after first look:
Plenty of room in the tender for a speaker and stay alive supercap....... as long as I modify the tender top and bottom fixing arrangements. A 21 pin decoder interface is already provided in the tender. However the rear tender-top screw receptacle pillar will have to be removed to enable a Zimo Dumbo 40x22x09 speaker to fit. I'll engineer an alternative rear fixing arrangement. If room is lacking for the stay alive capacitor, I'll put this (with its zener diode over-voltage protection circuit) in the coal hopper. The decoder will be a Zimo 644D with a Digitrains WD sound project installed.
A footplate crew will also be added.
If I'm feeling brave, I may also have a go at some weathering. I'm old enough to remember watching these locos in service up in Yorkshire and I don't think any that I saw were remotely as pristine as this example!
The locomotive running in DC configuration, straight out of the box is not too bad, but does exhibit some cyclical hesitation, related to the driving wheels angle of rotation. However, half an hours running-in on the rolling road after some spot lubrication of the coupling rod ends improved behaviour.
After previous Bachmann K3 difficulties I was concerned about how DCC running might turn out, worrying that some residual hesitation had to be a real risk.
Pondering out loud about possible reasons for this kind of rough running:
Thinking a bit more about the possible cause of a cyclical hesitation......
1) Faulty gear wheel on the driven axle (e.g. cracked).
2) Quartering error on any of the coupled driving wheels.
3) Rod clashes.
How to identify the problem? On 1) and 3) I think its mainly careful observation.
To accurately measure and fix quartering errors, some specialised kit is required. However, the normal consequence of small quartering errors will be tension or compression in the coupling rods and this maybe detectable. Also in the case of minor errors, it may be possible to alleviate the hesitation effect by elongating the holes in the end(s) of the affected coupling rods?
A 2.5mm AF "nut spinner" is on the way! (I used to call them box spanners.)
Fitting the Decoder, Speaker and Stay Alive capacitor:
The fit has gone exactly as described above:
The speaker wires, a ground wire and the common positive wire were carefully soldered to the Bachmann 21 pin printed circuit board. The speaker was glued to the rear underside of the tender upper body shell. Ground and common positive wires were routed into the coal hopper. The electrical tape ensures that the underside of the decoder cannot accidentally touch any live tracks on the Bachmann board.
The AVX super cap (6.8mF=6800uF at 15 Volts) is protected from excessive charging voltages by a simple zener diode regulator circuit.
That's a big relief! ........ DCC performance is OK. Not absolutely perfectly smooth, but its not bad at all!
Decoder CV Adjustments:
e.g. Some motor control adjustments: CV9 to 87, CV3 to 50 & CV4 to 25 (acceleration and deceleration rates), CV9 to 87, CV58 to 128.
chuff rate about right (4 per driving wheel revolution) with CV267 set to 70.
For use on our village layout, the active drive brake key is disengaged (hence the lower CV4 value) and a simplified standard sound key arrangement is programmed in place of the original Digitrains scheme described below.
Digitrains ZS003A on board MX644D Function Details:
|F5||Heavy Train (off) / Light Engine (on) Selection|
|F6||Coal Shovelling (This sound is also a random sound)|
|F7||Live Steam Injector (This sound is also a random sound)|
|F10||Safety valves lifted (This sound is also a random sound)|
|F12||Tender water filling|
|F15||Cylinder Drains Opened|
|F19||Fade All Sounds|
|F27||Overall Volume Down|
|F28||Overall Volume Up|
Adding the Detailed parts :
The loco and tender brake hose parts, the buffer beam steps and cylinder draincock pipes were super-glued in position.
Driver and fireman were selected from a Bachmann pack and also super-glued in place.
A bit of weathering :
I can't remember ever seeing a WD 2-8-0 in such a pristine condition! We lived quite close to the Doncaster to Lincoln freight line in the late 50s and early 60s and these locos were a regular sight, hauling long coal trains South and empties North. In fact quite a bit of that coal traffic may well have been routed through our present village on its way down to London, hauled by more locally based WDs. Such as the March based 90443. (last digit changed using Fox transfers.)
This is my first serious attempt at weathering. I don't want to have to use an airbrush, so instead, I've used a combination of Humbrol weathering powders, brushed matt enamel paint and a sealing coat of Humbrol matt enamel spray varnish. Possibly a bit heavy handed, but not a million miles away from the limited photographic evidence I've found and fuzzy memories:
March based 90443
Hauling coal empties