Rebuilding Lima Motors

A lot of people don't like Lima models for many reasons, one of which being poor running. Various solutions have been used over the years to get around this, apart from buying a different loco, those being re-powering the chassis with another chassis or installing a whole new motor, the sort of motor that is commonly found in the loading drawer to a CD player.
Over time I have found that the Lima motor, once properly serviced is not all that bad and that other options have their drawbacks. I have had a Lima 42 class re-powered by the use of an Athearn mechanism, this now does not go around corners well, and the body has been glued to the chassis by the previous owner so it would all stay together. This makes it rather hard to add new detail to the loco like flush glaze.
I have also come across a loco with one of the CD motor mods. This had the problem that there was a link gear from the motor cog to the original Lima drive cogs that had split on its metal shaft, in a rather similar way to the Trainorama/ Proto 2000 problem. In this case the engine has no drive at all. The motor just span. I ended up getting an old original Lima motor and putting it back in as the split gear was not able to be replaced.

The split gear is below the motor in the above photo. The motor itself also has to be mounted correctly, and in this case (by previous owner) it was not, causing meshing issues. Can see that there is one round hole on the mounting plate and one slot for adjustment for the other screw.

My experience in audio repair has shown that these motors are not all that great, they don't like running at low speeds for extended time, because when they are subject to this the commutators get filled with gunk, they develop partial shorts, and can stop running. It is impossible to successfully repair such motors, the usual fix is to install a new one. The open Lima pancake motor though is highly serviceable, parts can still be obtained, and the whole procedure is fairly straightforward.

First, the subject Loco, a Lima Alco 44/930 class, has its various drawbacks, but it has some advanatges in the fact that it is plentiful and cheap, rugged from a handling point of view, especially as little people always have to touch everything. With a bit of detailing it can be made into something quite reasonable, at a fraction of the price of an inflated price second hand one, costing almost double what they could be had for when new, that might still need work due to cracked gears anyway.

First, turn it over and remove the body screw in the fuel tank. I have a cradle to protect the paintwork and stops the thing moving all over the bench.

Pull the chassis out and put upright on the bench, put the body away somewhere safe. Remove the clip that has the wire attached from the dummy bogie by sliding it off. Then you can wiggle the power bogie out from its place.

Note the small weight in this one.
Now is the time to carefully remove the brushes. Do this by levering up the brass brush holder. Under this will be a spring. I am pretty careful and have never had a spring bounce on me but plenty of others warn about springs that jump at this point and disappear forever, you have been warned! Put these parts carefully away.

At this point it is worth considering the state of wear of the brushes. These ones here are just about new. The ones in the next photo have had it, replace when they look like this:

When the brushes get down to this point the whole motor becomes very noisy, especially when cold.
Now remove the cover plate by the two slot head screws. One some models you will need to remove the bogie side frames to get the cover plate out.

The part in the centre here that rotates is called the armature. The part of it we are looking at in this picture is the commutator. The brushes push against the commutator to alternately energise the different windings of the armature, producing motion. You can check the commutator for continuity at this point by testing adjacent segments to each other (the silver bits). With 3 segments this is known as a 3 pole motor. The brown ring around the armature is the magnet.
I like to clean the surface of the commutator and most other electrical bits with CRC CO Contact cleaner, this leaves no residue and is plastic safe as far as I can tell.

I spray a cotton bud then wipe around the contact surfaces. On really dirty ones, make sure you clean out between the segments, as carbon residue can cause a short circuit across the commutator segments. A toothpick can also help here.I then spray a pipe cleaner with the stuff and clean the insides of the brass brush holders. These conduct electricity to the brush, so it helps that they are clean.

Now time for the gears. Sometimes the intermediate gear has a 3mm brass hex screw on them, sometimes a clip, either way you will have to remove them. I do one from the motor to one axle at a time, so you have the other two for reference when putting it back together.At some point here you will need to remove the bogie frame, just two slot head screws from the bottom of the bogie.

Clean the gears and the axles they run on, clean out the centre of the gear with the pipe cleaner again. While you are there use the pipe cleaner to clean the oil out of the motor bearings. Can either use more of the contact cleaner or metho as a degreaser, it's only light grease/oil that you're getting rid of and you don't want to ruin the plastic with something stronger. Clean the teeth of the gears and look carefully, it's not un-heard of for casting debris from the factory to be left on a gear or two, causing a rough spot when turning. When re-assembled without the armature in is the best way to test for binding in the gears. Clean with a nylon brush or carefully with compressed air. Might need to remove any casting debris with a small, sharp hobby knife or pick. When putting the gears back put a tiny drop of oil on the centre of each axle, don't need any on the teeth, it will only pick up dust and fluff, this will create a grinding paste which will wear out the teeth.
Then slide out the electric pick up. This has a wire soldered to it to feed to the motor, it is quite common for this joint to fail. Now that it is out of the body it may be a good time to reflow this solder joint, less danger of melting the bogie.

This one is relatively clean, but where the axles rub on the ends of the tabs it can get quite black. Like this it can be cleaned with another CRC product, Lectra-Clean, this is much stronger than the CO cleaner, so avoid contact with plastics, as it may melt them. If it is really dirty then my preferred method is to use a dremel with a wire brush, if that is not available a metal polish and cotton bud will do.

Clean the axles while you are here.
This is the oil I like to use, Superlube, it is a light, synthetic oil that comes with a very fine applicator.

Then re-assemble the motor bogie in the reverse order. The narrow section of the brush goes to the spring, be gentle with the brass tabs, they don't need to be squashed right down onto the motor body.
Before replacing the bogie frame it is a good time to replace the traction tyres if necessary. The original Lima ones are probably impossible to find, and could also be 20~30 years old, even unused I would not bother with. Fortunately Fleischmann part no. 544003 fit and work well.
Now it is time to focus on the dummy bogie. You have already removed it, now need to remove the cover plate that holds it all together. There are some tabs on the upper side, these need to be pushed back with a small bladed screwdriver towards the centre of the bogie.

Take it upside down to get the plate out, don't drop all the wheels out, it matters which way round they go back.

Need to clean all the brass parts here again. Once again, the dremel with the wire brush attachment is best here. Need to polish the clip that the wire to the motor attaches, especially in the gap between the two halves. The retaining pin needs to be clean, especially in the groove that the clip goes into, and this makes the connection. Also the pin part where contact is made with the phosphor bronze wiper that contacts the wheels. Like the motor bogie the wiper needs to be clean as well as the axles. If you do drop the wheels you must put them back the right way. The axles are directly connected to one wheel, the other wheel on the axle has a plastic insulating bush. To work out which way round it goes, the insulated side needs to be on the opposite side of the loco than the wheels on the motor bogie with the traction tyres. As factory these locos pick up one track from the wheels on the motor bogie on the other end of the axle to the tyre, as the tyre does not help good contact with there rail. And the other part of the circuit from the other rail needs to be picked up by the wheels on the dummy bogie. So if in doubt, go back to first principles about electricity. Need about 3 or 4 hands sometimes to re-assemble this.

Once you have all this back together again, you can re-assemble the unit and test.

The you have one Lima that should work a whole lot better than it used to, maybe even better than it ran out of the box for the first time. The Lima motor has the beauty of being the same for almost all locos, just the gearing may change, so there are plenty of parts and should be for many years to come.
There are various other tweaks that can be done, like changing couplings, upgrading lighting and adding weight that can make them even better, can still even get detailing parts. I feel much happier knowing that children can touch this and not destroy it. They are going to want to touch, it's their way, and to take that away from them is hardly going to foster an interest in the hobby of model trains, they'll just go and do something else.

Building things

I've always liked building things, lego as a kid, then models, progressing through to much bigger things like sheds, house additions and furniture later in life.
I haven't built a plastic model kit since I was a kid. Most of these were done rather badly when I look back of them now, parts that didn't line up and glue everywhere were the main problems. Back then, the only glue I knew about was the stuff in small toothpaste-like tubes of cement of lots of different brands. They all had one thing in common as I remember, they formed string like mozzarella on pizza, and it got everywhere. Ian at Hobbyland in Hornsby put me onto some glue that was a revolution to me, thin Tamiya glue in a bottle with a brush built into the cap. The liquid being thin enough that capillary action draws the glue to where it is needed, not all over the model in places it is not wanted. I'd always heard about this type of glue, but I was sceptical, how could it possibly work?
I also bought my first kit in a long time, an AR kits MLE wagon, something simple to learn on. With the benefit of years of experience in tool usage now coming to the fore, and sharp knives, and a variety of them, this kit went together really well. It also helped that the parts were very well designed to go together and the instructions were very well written. Soon I had a model that I can be proud of.

I painted this in Model Master Gun Metal, can't bring myself to attempt weathering it yet, still practicing that.

Flushed with success I moved onto a Silverman S truck. Same paint colour, this makes it a just repainted one, and my first play with adding hand-rails.

The instructions weren't as clear as the AR ones, but the design of the moulding was done very well, and I'm quite happy with how this one came together.

Sticking with 4 wheelers I picked up a Berg's CV model. This one has not been so well thought out, the pieces are quite difficult to line up and the instructions were quite vague. However I did manage to get a reasonable model out of it in the end.

Painted this one in Tamiya German Grey, weathering of timber with SMS grey wash and metal with Model Master Oak wash, rust paint on the buffers and couplers.

At this year's Forestville exhibition I picked up some un-made AR NGBF wheat wagons. I added a bit of detail, not too much, especially underside, it's nice having detail under there, but at the end of the day, you generally don't see it, it can come adrift in the case of a de-railment, or the 5 year-old's friends will open up the display case...

I did this in Model Master Grimy black, and done a not too prototypical logo on it. I grew up with the L7 logo and really like it, it's my railway anyway...

Recently I have made a Sivermaz NGTY wheat hopper, to play with a curved body wagon, possibly went a little too dark on the paint job here, Railey Freight Wagon Grey, with a bit of PTC blue oversprayed at the ends. Some SMS grey wash was applied all over. I'm happy with this rather dark heavily weathered thing. Once it was weighted to a similar amount to an Austrians WHX and fitted with decent bogies, it rides very well too.

This was one of my first paint jobs with an airbrush.

I am in the process of finishing off a Camco FO coach, this was done in Railey Tuscan with the airbrush, roof in the Grimy Black, with added seats from Olddog. extra weight in the form of sinkers were added into the toilets, hidden behind the platform entry doors, and in the battery boxes underneath. Just got to work up the courage to place long decal stripes under the windows. I have 2 more of these kits waiting to be built. No 2 of them will look alike, they will be in Indian red, with silver and navy roofs.

Lots more of these to come. There's something most satisfying about building it yourself, they may not be perfect, but sometimes that's the charm of them. Some of the quite expensive new RTR stuff to my eye is a little clinical and cold, too perfect really, which for a lot of people is what they want, I suppose.