Archive for July, 2017

Push-Pull Train Development

Posted on July 22, 2017. Filed under: Project progress |

Scenery 42 170722 4528

54495 drew its five coach train forward from the south cassette until the rear coach was alongside the platform, and after a suitable interval slowly moved off onto the north cassette. It then reversed the procedure, several times. Each time it negotiated the transition from cassette track to layout track, and vice versa, and also the reverse curves of the loop point. And at various speeds.

Of course, this was to test a new engine. I started out with a target of only two coaches for a 4-4-0, thinking that was the minimum I could get away with at exhibition. After running in over several days its pulling (and pushing) power continued to increase. Similarly with 54458. The locos now weigh around 200 gm each, and the tenders a further 80 gm. The weight was distributed so the locos balanced horizontally about half way along their length, slightly ahead of the leading driver axle. The bogies have side control springing and take their proper share of the load.

That was only half the job. The train consists of four Hornby coaches, converted to P4, and a hand built TPO. The back-to-back measurements were carefully checked, and re-checked, and the wheels were accurately centred with respect to the axle pin-points before I could get them all to turn freely.

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June Progress

Posted on July 1, 2017. Filed under: Monthly progress |

The last south passenger train of the day calls at Culrain about seven fifteen in the evening. The Restaurant Car, which earlier in the day travelled north to Helmsdale with the HR TPO, now returns to Inverness. The TPO will return the following morning.

Train 19.15 Mid 1950s 170628 4519      Evening departure for Inverness

The newly applied lion-on-wheel symbol is just visible on the fully welded Stanier tender of 45473, which corresponds with the time period of the red and cream coaches, while the full brake behind the engine is in non-passenger coaching stock livery. The part welded Stanier tender, awaiting the building of a second Black Five, sports the later large BR totem to allow a change of time period to maroon coaches.

At the beginning of the month I learned a very important lesson during a visit to see the large, EM gauge South Pelaw & Stella Gill Flatts layout in Middlesbrough: it takes a determined and concentrated period of check/correct/review to prepare a layout for exhibition. The 20’ x 30’ South Pelaw is housed for 3 months in a large, open-plan area of an office building. It’s not planned to be exhibited for another year, a good clue for Kyle of Sutherland.

Kyle of Sutherland is currently going through a similar process in its 15’ home-based configuration with 2’6” cassette tables at either end, rather than 5’ exhibition tables. The train lengths may be restricted, but what a lot I’ve learned and applied. There’s hardly no aspect of the scenery, electrics, track, cassettes and rolling stock that hasn’t needed some sorting out.

Early successes include the LMS D1720 coach Sc6735M, which used to repeatedly derail near the south entry point to the passing loop. I blamed the MJT torsion bogie gummed up with paint, preventing it rocking smoothly. Not so: the culprits were the cosmetic side frames catching on the solebars on the point’s curves. The temporary cure was to raise the height of the bogie by the thickness of one washer. In the longer term, I will look more closely at the depth and position of the side frames. I suspect some other coaches could exhibit the same problem. All rolling stock is currently going through a programme of checking the back-to-back and overall weight.

I’ve been testing 54458 and 54495 on their return from the paint shop. In the final stage of modelling I removed their motors and worm drives while leaving the High Level gear boxes in place. This has allowed me to push and pull them around the layout with a small diesel shunter to check their running. Out of interest the shunter has over-scale, “easy couplers” at either end, which get round the problem of using the very fiddly scale couplings on Kyle of Sutherland’s rolling stock. Well, I found out more than I bargained for: the steps of both locos fouled several feet of the Up platform. The solution with 54458 was a combination of cutting back the wooden platform edging and supporting joists and bending back the steps. I’m not happy with the latter part of the remedy as it noticeably alters the appearance. I had the same difficulty with the bogie steps of the HR TPO and in this case I reduced the width of the step treads, which looks better. I’ll mull things over before addressing 54495. Even though the two locos only weigh about 90 gm without motor, tender and any added weight, they ran very smoothly throughout the layout and I may simply keep oiling and running them in this way for a while before replacing the motors.

The 10 train exhibition sequence planned for the layout involves uncoupling engines, turning and replacing them at the other end of the train. I’m minded to install easy couplers at the rear of all locos. As a result of this concentrated period of operation I’ve come up with some further ideas to improve the layout’s “ease of use” for other operators. There are also some train movements precluded by the design of the layout’s electrics. That’s more to think about.

I now understand the benefit of having a comprehensive set of specifications for all aspects of the layout and its stock. I’ve taken particular notice of the standards employed on St Merryn, the P4 exhibition layout built by the South London Area Group of the Scalefour Society. I’m constantly surprised how even the smallest departures from standard can cause derailments in P4.

All this confirms I’ve put loco building on the back burner. I’m first going to concentrate on proving, and maybe improving, the layout with my current stock of five steam and two diesel locos.

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    The epic struggle to build a model railway exhibition layout at 4mm to the foot


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