DCC Loco Conversions - 14 - Dublo - NEO ?

I first became aware of neodymium magnets back in 2005 when I had taken voluntary redundancy and decided to resurrect my interest in model railways.

Initially I started to expand my late teens Dublo collection via eBay, at the time if you had a loco with a weak or useless magnet the only alternative was to send it away to be re-magnetised.

Long before In the late 1960s I could get that done at a local model railway shop, and it was never cheap, by 2005 most local model shops had disappeared in the London area, I circled London on the Underground looking for model shops, most had gone or the owners were tapping away at keyboards for selling on eBay.

Box shifting shops such as Beatties were not interested in such services.

So for many of us the arrival of the NEO magnet presented an easy and relatively modest way of making our old locos run again. Many of my Dublo locos were fitted with NEO magnets as I bought them as part of restoring or overhauling them, many of which had seen a busy life on carpets and then rusted ignominiously in lofts and sheds for decades.

As time passed and my railway developed DCC became an affordable and highly desirable means of loco driving, so due to what was for most Dublo locos a difficult conversion process they sat in storage for the last 11 years or so.

Now I am up to the challenge they are being brought back to life again, in retrospect however NEO magnets are no longer quite the universal panacea they first appeared to be, especially now an affordable re-magnetiser is available which IMO works very well on both Dublo and Tri-ang Alnico (or Al-Ni-Co) magnets. Ref 14.1.

My initial concerns were that in smaller locos, e.g. tank engines and shunters the armature tended to jump between poles instead of smoothly transitioning from one to another, this is referred to as 'cogging'.

This video summarises my views on the subject very well :-



From various sources there is concern about excessive wear on gears and bearings, however it is documented that some Dublo locos could haul much more than any kiddy could have loaded them with.

In the book "Hornby Dublo Trains" by Michael Foster (Ref 14.2) there are examples, such as a Deltic hauling 51 wagons for 100 miles and a Crepello Deltic hauling 28 Super Detail coaches at a 1962 trade fair.

A Cardiff Castle hauling 20 items of rolling stock for 570 miles with just oiling and brush replacements

These locos with their original magnets were often formidable haulers, but how long would the motor bearings and gears have lasted on a daily basis with those loads?

So when NEO magnets are fitted to Dublo locos I expect that they are often being charged with heavy loads, much more than a kiddy with a wealthy dad to fund it could have been able to back in the 1960s.

Since modifying Ringfield motors for DCC recently I have found that the ball bearing at the top of the motor can get magnetised too, that cannot help matters as the ball sticks to the motor shaft instead of performing as a lubricated thrust bearing.

I also get fed up with everything I put near them, screws, screwdrivers etc also being magnetised, the occasional magnetic screwdriver is useful, but not all of them!

So when I see concerns about bearing wear mentioned it is often missing whether it was the side surface in contact with the armature shaft or the ends of the shaft that were worn. IMO it is most likely that a lack of lubrication was the main cause.

Gears will also be well punished through overloading, they like 1960s cars required far more maintenance per 1000 miles than cars of today, (I think my first car required me getting underneath with a grease gun every 3 months or 3,000 miles).

My View

Now that I own a re-magnetiser designed and sold by Ronald Dodd (Ref 14.1) I shall re-magnetise and refit the original magnets as I re-assemble the modified motors, luckily I kept them when I changed them to NEO 11 years ago.

I could also use a de-magnetiser now, probably one sold for watches is worth trying, I'll report back on my findings.


Discussion always

Jim

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References

14.1 Hornby Dublo Magnetiser update 2020 - Ronald Dodd



14.2 Hornby Dublo Trains - Michael Foster

Part of the Hornby Companion Series - Hornby Dublo 1938 - 1964

First printed by New Cavendish Books 1980,

My copy is a reprint of 1993 which includes many extra colour plates

 

Hi Phil, well magnetic materials technology has moved on since then and hopefully present locos use a more stable material, the Alnico magnets of 60 odd years ago were unstable as even dismantling a loco motor without a keeper (steel plate) across the poles could cause its magnetic field to collapse and weaken the motor, victim of that myself in the 60s when servicing a favourite loco. Nevermind I still have it and now re-magnetised runs strongly.

It was never anticipated that toys made for kiddies would still be wanted let alone used some 50+ years later, often todays 'model's have only 6 months to a year guarantee and the occasional 2 years, and even 24 hours continuous running before you replace the motor, as miniature motors are often unserviceable. So I am not sure how today's models will still be useable in 20 years let alone 50, but by 50 years I will be attending to the daisies.

 

So with a bench contaminated with magnetised tools and screws I bought a basic de-magnetiser from Amazon where you can pay between £9 and £20 depending whether you buy it from Amazon and receive in a few days or from China via Amazon in a month.

I went for a low UK price Amazon from UK and it was discounted when I bought it.

Small device 11 x 6 cms, larger items made need stroking over it, worked well, it came with a fitted European 2 pin plug but easy to change to a UK 13A (or what your country uses) and I fitted the plug with a 1A fuse, the mains cable core is very thin.

Just search Amazon for "Watch Demagnetizer,Blue Professional" for many prices and delivery times.



Jim