Saturday, 2 May 2020

Dream Operations.

A railway that runs well is a joy to operate. There will always be a few derailments due to operator error, pulling the wrong points etc. From time to time wagons will derail at one set location on the layout or another wagon will keep derailing on a set of points. All of this can be fixed to give trouble free operation of your layout.
 

 
 Another point to consider is if you run operations to a time table, derailments will cause all sorts of havoc across the operations session to the point where the session is out of control and may not be all that much fun.   
To have a railway that run well, their need to be a good interface between the wheel and the rail. Good track is a must, ask they say in the prototype you require a good top and line. In other words, the top of the track most be in line, no dips, no kinks, twists or holes. I can hearing many of you saying, branch lines are far from it. That’s true, speed is low, often low axle loads, and a big plus is the rollingstock has spring. Our models don’t have springs to ride out the up and downs, thus good track is a must. Time taken to make sure your track is good and in gauge will repay you many times over with good operations.
Modelling H0n3½ there are many issues that impact on that good wheel rail interface.
Over years they has been various track systems used along with endless wheelset manufactures.
 At first, Tri-ang TT3 equipment was used. The manufacture made both set track and rollingstock. Gem produced flex track and points, Peco had their Wonderful Wagon series, all British manufactures for 12 mm gauge.


In Europe there was Bemo (Fine and course systems) and Pilz, in later years we have Tillig and Peco pitching at the meter gauge modelling. (Approx. 11.9 mm gauge), Shinohara is H0n3½ track for the Japanese market (approx. 12.3 mm gauge), this track system is no longer available. Some track systems are code 83 rail, PECO is code 75 and Shinohara was code 70. In Europe there has been a number of manufactures of rollingstock, Berliner Bahnen, Roco to make a couple. On top of this some TT models were produced in the US for local modellers.

Gem Track and Points.
 
Shinohara Track and Points.
Bottom – Peco Code 75, Middle – Shinohara Code 70, Top – Gem Code 83 Track
 Various manufactures have made wheelsets over the years, some plastic and other were metal of various types. Jackson, Wren, Peco TT, P.M.H, K&M made wheels for 12 mm and H0n3½ gauges, AR Kits, Steam Era Models. Now we have CGL, Caintode Flats Models, Southern Rail and Wuiske Models all producing wheelsets. Some wheelsets made for Shinohara track do not run through H0m points. Steam Era wheelset ran on most track systems I used over the years. The cost of them increased and troops stopped buying them. Production of 12 mm wheels no longer takes place, 9.5 mm disc wheels are still available. To add to this you will find the axle length will vary considerably between the manufactures. This prevents exchanging wheelsets between the various bogies.
 
When you look at the standards there is MOROP (European), NMRA, AMRA and British TT/TT3 or 3 mm. All are difference in various ways. I understand there was an H0n3½ standard developed in the 1960’s with AMRA and NMRA, but I was never aware of it. I started QR modelling in H0n3½ in 1973. At the time it was mainly British equipment used, some being Tri-ang. By today standards I fell the standard would not be that great anyhow. A paper written by Peter Knife “Modelling Australian HOn3½” for the Second Australian Narrow Gauge Convention held at Blackheath in 1998 cover standards and the industry at that time. http://www.minnipasiding.com.au/hon42.pdf
Today, in short we have track manufactures who do not make rollingstock and rollingstock manufactures who don’t make track.
I feel I cannot change track standards or any other standard for that natter, the most accessible track system today is the PECO H0m track which is the cheapest and most workable for the modeller. In recent year most manufactures producing rollingstock have adopted RP 25 contoured wheels. The theory is that the wheel is less likely to pick points and go around curves better. The standard states the wheels are best on track conforming to the limits of NMRA Standard S-3.2 and consistent with RP-10, RP-11 and RP-12.  At first we had RP 25/110 wheels, the tyre was wider than the prototype. To get a better looking wheel RP25/88 wheel was used.  The table below will give a overview of the difference between the two.
 
Tyre Width
Flange Width
Tread Width
Flange Depth
RP 25/110 wheel
.110”
(2.794 mm)
.030
(.762 mm)
.080
(2.032 mm)
.025
(.635 mm)
RP 25/88 wheel
.088”
(2.235 mm)
.025
(.635 mm)
.063
(1.6 mm)
.023
(.5842 mm)
 Yes, the RP25/88 wheel looks good, but you need a track system to the same standard. If the track is not the same standard, the wheels leave the rail and trend to fall into a hole at the vee on points. Some manufactures have back pedal a little and now use RP 25/99 wheels. Wider the wheel type, longer the axle, wider the bogie becomes. Wider bogies can take the true porotype look from the model.
This raises two questions, Question 1. Does my PECO H0m track conform to NMRA standards?. Track manufactures give you a gauge and not much more. The biggest issue is the clearances in the points around check rails. I’m aware some Peco track in other scales don’t meet these standards, my HO code 100 track has modifications to stop derailments. Question 2. How do RP25/88 wheelsets behave on the layout? Some run like a dream, faultless, can be pulled and pushed within in a string without any issues. Others turn into kangaroos at points, jumping up and down. Once a flange arrives on top of the rail, it’s any ones guess where the wheel will go, but mostly it finds the ballast. If the wagon is in a train being pulled, with a bit of luck at the next set of points the wheel will bounce back onto the rail. If you are pushing a wagon, once a flange arrives on top of the rail it all over. On closer inspection to find the cause, I observed there are differences in the flange shape on some wheelset said to be manufactured to the same standard. The back to back measurement could also very between different manufactures.
I have a test track, all wheelsets are tested before they hit the layout. The back to back is adjusted so the wheel run freely through the vee. Sitting on a chair, I place the board on the top of my legs, this allows me to alter the angle of the board and adjust the speed the wheels/bogies rolling through the points. Allowing the wheels to roll at a slow speed will show where the wheels meet resistance or climb onto the top of the rail head. 
Wheelsets that don’t run smoothly through the points have the back to back adjusted. I use two pullers to adjust the wheels on the axle.   
Hobby Tools Australia. This unit pulls the wheels out towards end of axle.
 
This gear puller can move the wheel in or out with adjustment of the centre screw. The centre screw was drilled out and a brass wheel bearing was inserted. I mainly use this tool for moving the wheel along the axle. I use the two to save adjusting the setting each time. (Lazy ??)
A good set of Vernier Callipers can be very helpful when adjusting wheelsets. The newer digital type make it much easier to read if you a bushie like me.  
 
 
Some wheels are gauged a recessed flange in the axle which prevents the wheels being pulled inwards. I’m very lucky I have a lathe, a small amount is taken off the back of the flange helps to achieve a wider back to back. I also do this with wheels with thicker flanges. Spinning a wheel in the lathe will also highlight if the wheel is square on the axle, I’m finding some insulated wheels have a wobble in them, thus they don’t run true and can pick the vee in the points at various times. Rolling the wheelset on a sheet of glass or a flat surface can achieve similar results. This could be the result of how you pull the wheelset out of the bogie, check before and pull on the non-insulated wheel. So be careful how you put the wheelset back into the bogie.  
 If you have plastic wheels there is nothing you can do to alter the back to back other than replacing the wheelset. Over a number of years, all my plastic wheels have been replaced with metal wheels. Don’t toss them in the bin, more on that down the track.  
 
The freer the wheels, the better with less friction. I have a modified H0 bearing tool to ream out the axle boxes on Delrin/Acetal plastic side frames.
 
 
 
The wheels need to turn freely will little to no side play in the axle.
The key point I try to achieve with wheelsets is reducing the resistance within the bogie and it interface with the track. Free rolling vehicles that run well on the track will give you less derailment and smoother operations overall. It will also show up how level your layout is.   
I try to have 30 foot wagons around 50 grams. Four wheeled wagons 25/30 grams appear to work OK, four wheeled wagons are trouble at the best of time if you want to push long strings. Some of the early carriage kits have a block of poxy for the roof, some are more than 3 times heavier than the rest of the kit, making the vehicle top heavy. I ream most of the poxy out using a dermal milling tool in a drill press.
 
Centre of gravity is very important to any railway, the lower the better. When adding weight to a vehicle I like to add plumber’s sheet lead to under the floor.
 
Coupled to this is the mounting position of the coupler. Most scratch build wagons I make my own coupler box reducing the side throw in the coupler. The back of the coupler socket is set level with the buffers heads. All wagons travel through cross overs without issues.
 Coupler heights can also differ, in the early days most kits were manufactured using the standard H0 Kadee coupler heights. This is higher than the QR  2’ 8” coupler height. To keep everything in prospective I mount couplers at 9.3 mm to the centre casting on the Kadee. Wuiske Models adopted a similar height for their RTR rollingstock. Southern Rail Models producing a dual position coupler box to cater for both by moving a spacer above or below the coupler shaft within the coupler box. For my money, wagons with standard H0 coupler height sit up much higher and makes the model look top heavy. As much as possible I try to keep the wagon/carriage floor and roof line at the correct height. The trip pin can hang low and catch on points etc., I bent them up a fraction. Australian Model Railway Magazine published an article “Coupling up in H0n3½” (April 2001). Stephen J. Colclough shares some hard earned lessons with coupling Queensland Railway HOn3½ models.
 
Building you own couple box into the wagon has some advantages, many older timber framed wagons have the bogie mounted on the end of the wagon. Standard Kadee coupler boxes fit between the wheels, but don’t allow them to swivel on small radius curves. Kadee makes a narrower # 262 box which can be purchased separate and are much better for the narrow gauge modeller. Building your own coupler box you can alter the shape of the yoke protruding out from the headstock. This can give extra support under the coupler shaft to prevent couples from sagging. It also allows you to reduce the cross movement within the box stopping couplings pushing outwards when pushing back.  
 

Most QR RTR rollingstock on the market today will run on PECO H0m track, radius of curves can be biggest issue, some locos may have issues on the points. If it is any comfort, the 6 wheeled DEL bogie caused many issues at first on the QR. I find PECO points can lose their gauge in the switch blades, I hold the toe of the switch hard up on the stock rail and with the other hand apply a small amount of pressure to the middle of the switch (curved closure rail), care is need not to apply to much pressure so that it pulls the rail out of the heel block.
 
 
Trust this helps you enjoy your railway more.
 
Arthur.
 



 

 

 
 
 
 

 

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