Owing to my limited spase (7M x 4M) I find that point work is often approached by a downhill bends and that cross overs need medium length peco points. This coupled with protected sections which, in extremis, cause an abrupt halt have caused many over-run type derailments. Equally the trailing carriage seems to trip on the check rails. To overcome this I have fitted steel strip as ballast ( this runs bogie pivot to pivot so is well distributed) and brings the total carriage weight up to 200 grms from 130gm. This works! However, has anyone carried out any more trials and reached an optimum?
The other problem with the same areas are the new Pullman Wagons. The finer wheels simply refuse to remain on the rails when in the lead position ( ie with max lateral force on the bends). As trailing cars they seem OK. Not being too keen on tearing brand new kit to pieces I ask if anyone has tackled this problem - they are already heavier than their predecessors at 160 grms.
The problem of jumping bogies on my Hornby 4-6-0 locos seems to be limited by fitting part of an uncoupler (Hornby/Peco type) spring between the bogie chassis and the fixing screw. This acting as a single ended leaf spring with a very light action.
As part of curing this problem, I'd suggest you check the back-to-back settings of your wheels to make sure they're consistent and to the recommended 00 minimum of 14.5mm. Since the point of a checkrail is to STOP derailing, it sounds like you're getting binding or ramping on one of your axles which is going to create this behaviour (and check you haven't got a waggling wheel too).
200g sounds good to me. Strips of scrap roofing lead can do the job too, and consider putting weight low down such as in the back of battery boxes on the underframe. Plastic coaches probably are too light on the whole and as long as your trains will climb your ruling gradient, weight away (including more on the loco if needed as they can lack adhesive weight too). Remember that adding weight also increases wear so a parallel upgrade, if you've not already done it, is to fit Romford pinpoint bearings into the bogies and upgrade any plastic axles to metal. Hornby's ownbrand wheels, which come in bubblepacks of 10, are excellent and good value: I use them pushed out a bit to 16.5 B2B - and they will go a bit wider - for EM wagons, as they're (whisper it) all but finescale profile on Code 75 and a satisfactory alternative to my usual Alan Gibson or Kean Maygib wheels.
Good idea. A bogie is supposed to take carrying and steering loads, but on too many models it just "comes along for the ride", as Iain Rice puts it, and is so loosely riveted to its bearer that it can leap off in any direction if baulked. Again, check your B2B as anything leading is going to derail if it binds on pointwork.
I'm going to recommend - again, because it's good - Rice's book Locomotive Chassis Construction in 4mm Scale (published by Wild Swan). He delves a lot into the business of loading wheels for best running and suggests numerous ways of applying download using weight, springing and compensation as required. (A lot of bogie loco models are nose-light because the chassis weight's around the motor, so if you're springing the bogie down, you may need a dob of lead in the smokebox to level things out). Rice is also a great advocate of applying side-springing on bogies and trucks to ensure that they do what the prototype does and create side (steering) load as well as downforce, which matters strongly on pointwork. Fine piano wire or hard brass are good materials to use for this. Do read it - the book is of as much use to the improver of RTR as to the kit maker.
It depends on what track standards you are using and brand of wheel before a Back to back dimension is recommended. 14.5mm often is to wide for common RTR 00 wheels and track.
See my web page on the subject at
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200g is unnecessarily heavy.
Don't add the extra weight and then you don't have to worry about replacing bearings early on. For Peco 00 track a back to back of 14.4mm to 14.45mm works well for most wheels.
I have plenty pf models with bogies which go along for the ride, no bogie springs, no extra bogie mass and they stay on track without any problems.
I disagree with Ian Rice when it comes to side springing on small scale models. It is an unnecessary complication which makes no difference to the appearance of how a model tracks. Thousands of RTR models on the market that work prove this point. Adding springs in most cases results in a significant decrease in tractive effort of the model.
Terry Flynn
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HO wagon weight and locomotive tractive effort estimates
Try Hornby wheels from a few years ago. It's also to wide for wheels built to NMRA RP25. Finally 14.5mm is an ancient wheel back to back dimension from a flawed standard.
Terry Flynn
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HO wagon weight and locomotive tractive effort estimates
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