ringfield upgrade Ringfield conversion to CD Motor. Is it worth it?

[Esmedune]

I am looking at upgrading a Hornby Class 86 motor. I have serviced the motor and it works well enough, but has fits and starts at low speeds, so I was looking into the bodge fix of replacing the Ringfield motor with the motor of a CD/DVD player.

I was looking at the Strathpeffer Junction kit (https://www.strathpefferjunction.com/product/Hornby-ringfield-replacement-6v-cd-motor-adaptor-kit-ha2-12mm-bo-bo/), but his disclaimer has quite a few "don'ts" that are probably not a concern with the original Ringfield.  So I am wondering is it worth it?

Is there a more modern motor bogie that will fit in the 86, or is the payoff of the CD motor worth the drawbacks?

Edited May 18, 2021 by Esmedune
Typo

[d00m]

CD/DVD motors are usually a lot smoother than the original Ringfield. Personally I would go with  the 12v version.

[andyman7]

A CD/DVD motor conversion lowers the current draw and is therefore an advantage with both DCC and modern electronic controllers. But a properly serviced adjusted Ringfield motor can actually produce a pretty good performance - the main shortcoming for the pre-China models is the lack of pickups and weight. Fitting all wheel pickups and adding some weight makes quite a difference. The Traction Tyre wheels can be swapped out for trailing bogie wheels which conveniently also have the gear tooth moulded in.

[Phil Himsworth]

I recently converted an old Hornby class 47 and it worked so well I did a couple of others too. The motor in the first was a bit ropey, had a quite high minimum speed and seemed to spend more energy buzzing while going nowhere than actually moving.

 

The 6v CD motor is noticeably less powerful; it slows down around tighter corners where it didn't before. It is a lot smoother, quieter, has a much better minimum speed, and the motor seems to act as a flywheel more then the old one did so I think it's a bit more tolerant of bad electrical contact. You can push the loco along the track and the motor will turn, whereas the old ringfield it was very difficult to turn the motor from the wheels.

 

Mine were done using the similar kit from Horns and Whistles on eBay. I don't know if the Strathpeffer one is the same but it did require drilling the bearing from the old motor housing, so it is not a reversible process. Still worth doing in my opinion.

 

I've got one more ringfield loco and one more conversion kit for it; this one runs better so I'm not doing it just yet but it will probably get done in the future.

 

[The Johnster]

The ringfield pancake motors of the 70s, 80s, and 90s were not RTR's proudest moment (though the intentions were good), but it is I think informative to understand the reason for their use and adoption.  If one winds the clock back to the late 70s and early 80s, the new kids on the block were Airfix, Mainline, and Lima, and, for the first two in particular, much was made of the realism of steam outline models which featured, among other improvements over what had gone before, daylight visible beneath the boilers where it appeared on the prototype and properly moulded boilers without 'skirts'.  This could not be achieved with the 'conventional' layout of an open frame motor driving through a worm to a gear mounted on the driven axle; it needed a pancake motor mounted transversely in the firebox or tender, and driving through a series of spur reduction gears.  The motors were not very powerful, so they had to run at high rpm to develop usable grunt, so the spur gears were needed to bring things down to an acceptable level of rpm at the driven axle, and traction was helped by traction tyres despite the deleterious effect they had on pickup and track hygiene,

 

An advantage for the manufacturers was that a standard motor could be used in diesel or tender drives as well as in fireboxes, and the motors were reliable and easily maintained.  The problems arose with the spur gears, which were plastic, wore out of alignment, and split easily.  Cab detail had become a desirable feature of RTR locomotives and the pancakes prevented it on some steam tank locos, including the Lima J50 and 94xx, the Airfix 14xx and 61xx, and the Mainline J72, 57xx, and 56xx; worse still was the Mainline 32xx which had the rear of the motor clearly visible in the cab. 

 

Performance could be reasonable if the motor was set up well and the gears meshed properly and were in alignment.  On early Lima models the brass alloy wheel rims attracted dirt and the models had to be kept scrupulously clean to have any chance of decent slow running, and Mainline's split chassis pickup led to a plethora of issues that affected their models though their pancake motors were probably the best in terms of quality.  Tender drive pancakes were produced by Airfix, Lima, and Hornby, all of them featuring the attraction of spur gears visible below the tender side frames.

 

Modern production uses can motors driving through idler gears to the driven axles, which enables powerful worm drive motors that allow the gears to be hidden and daylight to be visible where it should be; performance is generally about as good as it is reasonable to demand from volume produced mechanisms at the price level the market demands.

 

The replacement of pancakes with CD motors is not something I've ever done, but if the spur gears can be dispensed with I'd say the results will make the effort worthwhile.  As I have an old Lima dmu which I've rebuilt as a 116 which gets an occasional outing, I may even have a go myself one day!

[DCB]

Fits and starts at low speed sound like pickup issues.  The replacement CD Motors have a lower current draw so they will suffer even worse from poor pick up.   I have been using these motors for well over 10 years, they are great replacements for the cheap and nasty ring fields in Lima power bogies but the Hornby is much better engineered, especially the commutators.   Common fault of Hornby Power bogies is the inability to keep the trailing bogie wheels clean enough to give a proper pick up.   Most Hornby power bogies have tiny wheels, vastly under scale so they aren't that useful, I have used Tender drive units instead which have much nearer scale wheels for Diesels such as 37s and 47s and for which the Tender drive is almost a direct replacement

Edited June 23, 2021 by DavidCBroad

[melmerby]

The Airfix 14XX & 61XX did not have pancake motors (neither did the N2 Airfix/Mainline), they had conventional in line motors.

Airfix used ringfields for tender drive locos.

 

Beware using CD motors, some are as low as 2.7v rating.

[Barclay]

With your class 86 I would definitely try adding extra pickups and weight to the trailing bogie before considering a re-motor. My old class 25 ran beautifully after this treatment. 

[The Johnster]

On 23/06/2021 at 23:21, melmerby said:

The Airfix 14XX & 61XX did not have pancake motors (neither did the N2 Airfix/Mainline), they had conventional in line motors.

Airfix used ringfields for tender drive locos.

 

Beware using CD motors, some are as low as 2.7v rating.

This is correct, and they did not have cab detail either.  Airfix (and Lima & Hornby) tender drives showed the spur gears below the bottom of the frames, and they attracted attention to themselves in motion, especially at low speeds.