Model Railway Forum

Hi Everyone

As you will no doubt gather, I have a model of the subject loco,. Its a good little engine which I have improved by way of adding extra pickups to the rear driving wheels as the loco only collected power via the leading and middle axles when it arrived.

Power collection has since been further enhanced by coupling a parcels coach which has been set up with my self made pickups and connected to the motor. This further helps the loco navigate complicated sections of track where there could be many turnouts and diamond crossings to pass through especially if they are all insulfrog.

Now onto the question, the loco only drives on 4 out the 6 driving wheels and I am just wondering if anybody has previously tried to adapt the coupling rod ( assuming it is possible to do so ) to turn the 4 wheel drive loco into a 6 wheel drive beast with much improved traction and the ability to haul or shunt trains of a reasonable length.

Currently the loco ( with its power collection coach ) will comfortably haul 4 suburban coaches, 5 with a bit of wheel slipping but 6 is a total impossibility even with huge lump of weight the loco was given when it was produced. My hope is to potentially change out the wheels which are on the 2nd driving axle for a pair of hornby 9F wheels ( 1 axle set with 1 conductive wheel and 1 isolated wheel 1980s / 90s version ) as they appear to be the same size and I think a conductive wheel or a full set of 1980s / 90s wheels would help to improve the loco .

Any thoughts on this are welcome and appreciated and my thanks in advance for any replies given.

I have been looking at a similar chassis I picked up cheap in a toy and train fair, and I was looking to make it into an 0-4-0. The conclusion is that due to the middle wheels having slightly different height to the axle centres and are allowed to float a little, when I looked into converting it to an 0-4-0, the only option was to make a new chassis. I started doing this but then a housemove took priority and I don't even know if I still have all the little screws and cogs etc or where it is at this moment, so I didn't complete the build.
But as an 0-6-0, I would say it is easier to look at building a new chassis. The Con rods can be altered or new con rods made, and one needs to have an accurate means to drill out the holes for the axles. The design of the motor and gears needs careful consideration on how to attach the motor to its new chassis. It can be done but it is likely to be the same amount of work as building a new chassis from scratch with new wheels, conrods etc and a new motor with conventional worm drive just to simplify things. Not to say that building a chassis for the Lima motor and wheels can't be done, and the advantage of a new chassis will be that it is going to be more rigid so by nature of chassis designs, rigid chassis with less flex are usually more successful (Providing all the axles are lined up correctly). Having said that, we can also come into chassis compensation to hope to improve things further but can be a can of worms and back to square one as Lima central wheels were made to "Float" in a semi-compensated way (But not for the same reasons as a purpose built compensated chassis. Lima made them float slightly to prevent derailments andprevent the centre wheels (Which they designed to be unpowered) to get in the way of the wheels providing the traction, as Lima were in their day tapping into the British market so had to come up with economical designs to attract customers with providing models that ran ok, looked attractive at a good price.
If one sees some Lima H0 models where Lima knew they had a better budget as customers were willing to spend more (Or the UK import taxes could be higher so Lima had to compensate), some of those designs were impressive, and one would not know Lima made them until one removed the body and found their pancake motor, or got ones glasses on and saw "Lima" on the underside! But quality wize, some of their H0 items designed for other markets were amazing!

Going back to the GWR loco, have a look at the axle heights of the Lima chassis and see if they line up as I believe (If they are thr same as the chassis I had which could have come from a J50), they will not be set at the same height which could cause issues if turning them into a 6 wheel drive loco.

Many thanks for your suggestions, if I remember correctly, there was a point about 6 - 8 weeks ago where I had to remove what looked like a spring loaded contact from inside the chassis which of all things, is made of plastic

The removed piece was very similar in its appearance to the pickups as would be found on lima bo bo diesels but it had to be removed as there are a few bumps in the tracks and as a result the loco derailed in both directions.

Luckily since the removal of the spring loaded contact which served no purposes regarding power supply to the motor, the loco rarely derails now but it does need some work to improve it.