naugytrax

Dave: quite right, somehow I got it confused with the H-D green EMU (2250), referenced in the Servicing Leaflet posted above. A temporary memory glitch; sorry, guys. Mike: I believe there should be a washer on top of the trailing bogie. I may have removed it from mine when I fitted smaller wheels. The pivot bolt for the trailing bogie goes through the hole nearest the coupler. The other hole may be for use in the Class 20 loco? Yes, that's the short bolt. My magnet was weak, too. Rather than pay to have it remagnetized, I replaced it with a Neodimium alloy type.

Mike, from your photo it seems clear that you have the Wrenn version of the "Belle" (W3006/7?), which has a quite different mechanism from the earlier Hornby-Dublo version and, as you say, uses the same power bogie as the Class 20 Bo-Bo. I took mine apart to compare with yours (well, mine has been modified a bit to improve the electrical pickup) and this what I found: The power car is held together by three bolts, one short, one medium and one long. The short bolt passes up through the central hole on the bogie-linking bar (nearest the power bogie) and into a threaded brass stud molded inside the roof of the body at the cab end. The bolt carries a solder tag with a wire connected to the insulated brush on the motor. To tighten this bolt you have to work through the rectangular hole in the underframe. The medium-length bolt passes up through the central hole in the underframe, through a brass spacing tube, through the end hole of the bogie-linking bar into a brass stud under the center of the roof. Thus there are two bolts holding the bogie-linking bar to the body and it's quite rigid. The long bolt forms the pivot for the trailing bogie. From the bottom up, it has a washer and a short (3/8 inch) spacing tube which goes up through the bogie, through the boss at the end of the underframe, through a longer spacing tube and into the brass stud at the non-cab end of the roof. The brass studs at the outer ends of the roof are connected on my model by an inductor for RF interference suppression. This could probably be replaced by a plain wire nowadays. The long pivot bolt completes the electrical circuit from the non-insulated trailing wheels and bogie, the two outer brass studs, and the wire to the insulated motor brush, thence through the motor and to the non-insulated brush through the metal bogie and its non-insulated wheels. While you've got it apart, you might want to install a flexible wire between the trailing bogie and the brass stud at the non-cab end. I found that this makes the continuity more reliable. (I also fitted electrical wipers on the insulated trailing wheels, and on the adjoining parlor car, but you may find this extra work to be unnecessary.) Good luck! Humphrey

How about a WR gas turbine? Ran regularly on the main line in the 1950's, and certainly looked nothing like a 1930's King!

Based on the tread profile, that wheel is intended to carry a traction tyre. Which is odd, because I thought that VITrains locos had 8-wheel drive with no tyres. Could a previous owner have swapped something?

When I re-wheeled my Triang/Hornby "Hall" tender I used common-or-garden 16 mm wheels. Romford/Jackson, I think, but Markits, Gibson etc. would do just as well. The odd quarter millimeter difference in height isn't noticable.

Northwest Short Line sells "shaft adapter bushings" including 2.4mm (3/32inch) OD, 2.0mm ID. I used one to replace the Airfix motor in my GWR 14xx with a Sagami unit. Their catalog is here: https://nwsl.com/collections/shaft-adapter-bushings/products/bushing-shaft-adapter-reducer-2-0mm-id-x-2-4mm-od-x-3-0mm-l-steel-2-pkg They seem to have closed for the duration, but I expect they'll be back when this unpleasantness is all over.

I have a Mainline 5600 Class running on a Bachmann mechanism. The bits fitted together well, although I think the brake shoes were mounted differently so there had to be some bodging in this area. The Bachmann mech runs so much more smoothly than the Mainline original that I would recommend retaining it if your dug-out model turns out to be a Bachmann. Have you considered stripping the body (e.g., with brake fluid) and respraying it? The BR livery for a 5600 is dead simple, and even the GWR livery has only two-and-a-bit colors.

For close coupling within the rake, I'd suggest Keen Systems couplers, like https://www.keen-systems.com/Fits To.html. At the outer ends, use Kadees as Melmerby said.

In the specific case of Bachmann Mk.I and Mk.2 coaches, a simple fix is to replace the coupler arms with the correct-shaped (cranked) ones available from Keen Systems. I've always suspected that when Bachmann designed their close-coupling system, they simply copied the parts from Roco's HO coaches, not realizing until too late that OO coaches have higher floors!

Many years ago I re-wheeled and re-motored a Wrenn "Castle", as much as anything to get rid of the unsightly Ringfield motor which filled the cab and which was nowhere near as controllable as the marketers had led me to expect. The 5-pole motor came from Scalespeed and bolted right in with no need for an adaptor. As far as I know, Scalespeed still has them available. There are two types for the Castle: one replaces the old Dublo "half-inch" motor. Mine still runs beautifully.

When the pad on my ROCO-CLEAN gets dirty, I clean it with IPA. No signs of disintegration yet! But like all flat pad cleaners, it only does the top surface of the rails and doesn't shift much muck from the top "inside corner" of the rails, which is where the wheels (if properly profiled) actually make contact - physical and electrical. To clean this area I use the little whitemetal cleaner wagon kit from Wills which drags upright cigarette filters, moistened with IPA, along the top and shoulders of the rails. It finishes the job nicely.

"The effect can be mitigated by equalisation or springing." Perhaps I was doing it wrong, but in my experience 4-wheel wagons and bogies with equalized or sprung suspension are more likely to "fall into the gap" than those with rigid suspension. If the orientation of the axle over the crossing is fixed with respect to the other axle(s), the other wheels will tend to "carry" the unsupported wheel. A flexible suspension just pushes floating wheels down to drop into the hole and bump into the crossing nose on the way out, causing them to jump and possibly derail. "A rule of thumb...should be met by BRMSB and NMRA as well but the sloppy tolerances of most ready to lay track prevent it" This is borne out by Shinohara Code 100 turnouts, which are built exactly to the NMRA standard (S-3) with no extra slop. Standard wheelsets never have a problem with them. "Hornby Dublo used this method" Also Maerklin, of course. (I think they still do.)

"Not sure how you integrate Diode matrix with individual CDUs." Here's one method which has been found to be successful and reliable: Each of the individual CDU's has 4 terminals: common negative, positive 20V for charging the capacitor, and one control input for each direction. Each control input grounds the base of a general purpose transistor, which turns on a Darlington pair which connects the capacitor to the turnout motor in the desired direction. Leads from the CDU to the motor are thick but just a few inches long. The Diode Matrix, on the control panel, has one input per route and two outputs per turnout motor as usual. However, since the (microscopic) current is flowing from the transistor base to the negative supply, the diodes are wired the other way round from usual. Together with direction indication leads from switches on the turnout motors (using the same common negative), the system uses 6 wires per turnout, but since the currents between control panel and CDU are small, six-wire telephone cable is quite adequate and the cable runs can be neat.

On the Mainline chassis, thin springy metal strips are bolted to the brush holders. They press on to the chassis halves, one on each side, to provide the electrical connections required to power the motor. If the chassis bolts are loosened, or the motor is otherwise disturbed, contact may easily be lost on one or both sides. As 34B-D says, strip it down and try re-assembling it. But pay particular attention to the springy strips where they are supposed to bear on the chassis metal, and maybe file or sandpaper some paint off the contact areas. Worked for me - but after a while I substituted a Bachmann chassis because it was smoother and quieter!

Pale blue for the walls. It's approximately "sky blue" but of course the real sky is not always the same colour. On the floor I have some rugged non-fluffy variegated green carpet. The overall feeling is more like the real world in miniature and less like an engineering lab!