How I constructed a pair of diesel locos from downloaded 3D files

Having acquired a 3D printer (see How I assembled my (very) cheap 3D printer) and printed out various small items for the railway, I felt the need to tackle something a bit more ambitious. On Thingiverse, I discovered Arockstone had uploaded the parts needed to make a small diesel loco based on an IP Engineering motorised chassis. In addition, Clarionut had made some additions and modifications to the parts to produce a slight variation on the basic loco.

The parts for both the original loco and the variant were downloaded and printed out. They were cleverly drawn so that for most of the parts, no additional supports were needed, apart from the cab roof and the handrails. I eventually gave up on the hand rails as I decided they were very fragile and I decided they could easily be made from brass rod.

A .pdf document describing the construction process as also downloaded and I used this to guide the assembly of the parts. 

The underframe was constructed first ......

A straightforward process of joining five parts together using, in my case, thick (High Viscosity) Superglue from Tool Station.

The four sides of the cab were then attached, .....

...... followed by the three sides of the engine compartment.

For one of the locos, I bought the IP Engineering budget chassis kit recommended in the instructions but, for the second loco, I decided to use the 3D printed chassis supplied with the kit. Brass top-hat bearings (from IP Engineering) were inserted into the axle holes.

20 mm diameter wheels and axles were bought from IP Engineering as was a small motor and some gears. These were put together using the relevant holes in the chassis frame.

From past experience, I have learned that the pulling power of such a chassis is greatly enhanced if Delrin 8-tooth sprockets and chain are added. These were purchased from MotionCo and, after a bit of fiddling, fitted to the chassis.

At this stage, I decided to do the wiring. I found that two 14500 (AA sized) lithium cells fitted snugly inside the control panel in the cab which is provided with the variant, together with a Deltang Rx65b receiver/controller.

A SPDT slide switch was fitted to the aperture at the base of the panel fascia.

The charge socket was positioned between the wheels on one side of the loco.

The wiring for this loco follows my usual pattern, the only difference being that I replaced the toggle switch with a slide switch:

The two component parts of the bonnet top were then glued together and slotted into the top of the engine compartment.

After some test running to ensure that the loco ran smoothly, the mechanism and wheels were masked with tape ready for a visit to the paint shop.

A couple of coats of Halfords grey primer were applied from a rattle-can aerosol. These were carefully rubbed down .........

......and another couple of coats applied.

The underframe and cab interior were then masked .........

...... and a couple of coats of Halfords Rover Brooklands Green applied from a rattle-can aerosol.

The underframe was then brush-painted with black acrylics and the buffer beams picked out in red, 

Various details were now added, such as the windows......

...... the exhaust pipes. .......

..... and headlamps, which were fitted with tiny LEDs.

As I decided not to try fitting the 3D printed handrails (which I found tricky to print and then tidy-up), I painted some cast whitemetal handrail knobs (from Garden Railway Specialists) the same shade of green .....

...... and threaded some 1.5mm diameter brass rod through them.

Holes were drilled in the cab sides ........

...... and the handrails glued into place with thick superglue. The excess handrails were snipped off after the glue had set.

The diesels were then coupled-up ..........

...... and given a few test runs.

I then decided to install couplings and buffers so they could be used with my rolling stock. As the buffer for the stock on my railway is higher than the buffer-beams on the locos, I created some risers for the buffer beams from plasticard .......

..... on to which the buffers could be attached

Bespoke hook and loop couplings based on my generic design were then fashioned from wire and attached to the buffer beams at the requisite height to engage with those on my other stock.

..... and more test running was carried out.

At first, only one loco was powered but it soon became apparent that, to cope with the 1:40 gradients on my railway, both would need to have motors installed, and so the second loco was duly equipped - with its motor connected to the output from the Deltang Rx65b.

In addition, name and number plates were designed in TinkerCAD and 3D printed.

The diesels have entered service and do stirling work on the Copper or and Sand Quarry trains.

Conclusion

Since constructing these diesels, I have gone on to designing my own locos in TinkerCAD and printing them out - see for example, How I constructed a Schull and Skibbereen Nasmyth and Wilson loco. One of the things I have learned from constructing these little diesels is to ensure that the loco is broken down into a series of parts which are simple to print, with no (or the bare minimum) of support structures needed.

I have not, as yet, started producing my own powered chassis - I generally use motor blocks from ready-to-run locos. But my next project will be to design, draw and 3D print a complete loco from scratch.

Battery Loco Survey Part 2

 Following on from my previous survey of battery locos, which was designed to address a particular discussion I was having on a forum about the efficacy of battery v track power, I realised there was some important and more interesting information which I hadn't included. And so, a new survey was devised. The results from 212 respondents are now in.

As you can see, the majority of respondents (145 or 68.4%) are UK based which is hardly surprising as I am UK based and the Facebook groups and forums I publicised the survey on were also UK based.

Other countries were represented as follows:

• Ireland - 2 (0.9%)
• Germany - (0.9%)
• USA - 33 (15.6%)
• Canada -7 (3.3%)
• Australia -14 (6.6%)
• New Zealand - 3 (1.4%)
• Norway - 2 (0.9%)
• Hong Kong - 1 (0.5%)
• Isle of Man - 1 (0.5%)
• Switzerland - 1 (0.5%)
• Hungary - 1 (0.5%)

The majority of respondents (42%) are SM32 modellers, which is probably a reflection of the UK bias of those responding. The next most popular group are those who model in G scale (standard gauge) at 26.4%, closely followed by G Scale (metre gauge) at 16.5%. Then comes F Scale (ie 15mm/1ft on 45mm gauge track) at 8.5% followed by SM45 at 7.5% and then 0 gauge, 5" gauge and 7/8" scale on 45mm track each with 4.2%. This means 45.5% of respondents use 32mm track, 48.5% of respondents use 45mm track and the remaining 6% use a variety of  other gauges from 16.5mm to 7.25".

Exploring the data further, there are quite a few respondents who model in a range of scales and gauges. As might be expected, seven respondents run both standard gauge and metre gauge models on their 45mm track, five run O gauge and SM32 models on their 32mm track, and several modellers have access to both 45mm and 32mm gauge track.

10.4% have just one battery loco, 46.2% have between two and five battery locos, 24.5% have 6-10 locos, 7.5% have 11-15 locos, 4.7% have 16-20 locos and the remainder (6.6%) have 20+ locos. There seem to be a lot of battery powered locos out there!

The next chart is a bit tricky to see on a blog page, but I'll try to interpret it for you. 

The 212 respondents between them have approximately 1550 battery powered locos - which means on average, each person has roughly 7 battery powered locos. Of these, approximately:

• 694 are diesel outline locos (45%), 
• 117 are petrol outline (7.5%), 
• 552 are conventional steam outline (36%), 
• 37 are vertical boilered (2%), 
• 98 are battery electric (BEV) locos (6%), 
• 9 represent locos powered by overhead cables (0.6%), 
• 13 are electric outline (other) - maybe trams? (0.8%)
• 34 are battery powered locos described as "other" (2%)

When it comes to the origin of their battery locos, approximately:

• 22.5% were bought readymade;
• 26% were converted from track powered locos;
• 22% were built from kits;
• 5% were built from a 3D printed kit;
• 1% were downloaded from the internet and 3D printed;
• 5% were scratch-drawn and then 3D printed;
• 17% were built from scratch;
• and 1.5% were 'other'.

When it comes to the types of battery/pack powering the locos:

• 14.2% use non rechargeable cells;
• 13.7% use a commercial NiCd pack;
• 5.7% have made their own NiCd packs;
• 37.3% use readymade NiMh packs;
• 20.8% have made their own NiMh packs;
• 36.8% use lithium-based commercial packs;
• 16% have made their own lithium based packs;
• 7.1% use lead-acid batteries;
• and 2.5% use AA rechargeable cells (maybe NiMh?).

NOTE: Several respondents use more than one type of battery pack which is why the percentages are skewed.

It's unsurprising (to me) that most people use NiMh cells in their locos - they are a proven technology, and have a reputation for being easy to charge and safe to handle. Quite a few people () are now using lithium-based packs - despite the horror stories which circulate from time to time about their propensity to explode or catch fire. 

Most respondents (30%) have only one charger. Of those with more than one charger, 36.2% use them for different types of battery pack - in some cases a specific charger will have been supplied with a readymade loco. 14.3% only use one charger and keep another as a spare and 20.5% use their other charger(s) to charge more than one loco at a time. 

11 people (5.2%) say they use their charger(s) so they can charge during running sessions (and one of these says he uses them when he goes to shows) and only three people use a fast-charger. 

I was very interested in the responses to the next question about the control systems being used. I was very surprised to see that the majority (20%) have locos which are controlled manually - ie with a switch and/or knob on the loco itself). It seems that quite a few of us like to see a loco pottering about on its own.

Another surprise was the popularity (19%) of Deltang-based RC equipment. As someone who used to make and sell Deltang products I was aware of how many I personally was selling, but not really conscious that they were market-leading to that extent. I suppose it's because they were one of the first systems which were designed specifically for use on model railways.

At 14%, Loco Remote is clearly making an impact on battery loco users - which is not too surprising as the system is very reliable and does away with the need to buy a transmitter.

Quite a few (18%) make use of joystick or trigger transmitters - probably owing to their widespread availability and price. Also, most of the battery loco owners have live steam locos (see the previous survey) and so it makes sense to share the equipment.

Fosworks/Omni is making some inroads (4%) though this is difficult to judge as Fosworks originally marketed Deltang equipment and now also sell Timpdon systems.

It's interesting to see that 3% use homemade control systems and there is a good range of other control systems in evidence. Several respondents listed more than one control system which suggests that some may have changed their systems over time or are experimenting as newer systems (eg Loco Remote) are marketed.

Although the next question was asked in the previous survey, I included it again and, by making use of the previous responses, made it more focused. The most popular reason for having a battery loco (52.8%) was so that people could have something up and running quickly. Some commented that this was in comparison to live steam locos - or they could be running something while live steamers were being prepared.

30.2% use them because they have constructed them themselves. One respondent commented that while he didn't have the skills to make a live steam loco, he could make a diesel outline battery powered loco.

29.2% like battery locos because they can be made to run slowly and sedately. Maybe this is in contrast to some live steam locos which aren't quite as easy to control. In my case, coming from track power, it was a delight to be able to run slowly through pointwork without the loco stalling. It seems that 25% of respondents made the same journey as me.

In the first survey, several people mentioned that batteries were the most sensible way of powering a diesel / ic outline loco - and 26.4% of respondents in this survey agreed.

18.9% use battery locos because they are cheap and easy to build and 20.8% because they are cost effective.

15.1% wanted something as an alternative to live steam, while 7.5% wanted something to be able to rescue failed live steam locos.

14.6% wanted something children could use and a further 12.7% liked them because it was easy to add soundcards and yet another 12.3% liked them because it would enable them to have something on their railway which was unique.

Eight people mentioned they were useful to have with track powered systems as they could be used to clean or clear the track.

NOTE: As respondents could choose more than one response, the percentages are skewed

The majority of respondents (69.8%) have their batteries contained and charged within the body of the loco itself, while 46.2% have removable packs or cells for charging outside the loco. 28 people (13.2%) use a trail car/wagon which is connected to the loco with a trailing lead.

NOTE: Respondents could opt for several responses which is why the percentages are skewed.

These are the recommendations which respondents would make to anyone considering going for battery powered locos. The comments are reproduced here verbatim (apart from the correction of typos) and I have tried grouping them together thematically:

General advice

• The best thing since sliced bread - yes really!
• Like blondes and and brunettes we all love a steam loco but we marry a battery loco :-)
• Try it and see..
• Research to find the best solution for your needs
• Go for it! Plenty of plusses and no real minuses
• There are people far better qualified to give advice than myself.
• Go for it.
• Just do it, it is your railway, do what you like and enjoy
• Try and standardize your equipment as much as possible so you can share transmitters to save on cost.
• Do it!
• Just do it!
• Do it!!
• Do IT.
• Read Rik's blog!
• Yes, seek expert advice from people who know more than you ever will on the use of battery power.
• Go for it
• They are: easy to get running; cheap; slow running essential for me. They solve all the track issues I had with track power.
• Easier & cheaper in the long run for any layout more complex than simple loop(s).
• No track cleaning. More reliable
• Just do it - and yet be mindful of battery packs swelling in-situ, check them routinely. The current draw that we need for our locomotives is far less than model helicopters, aeroplanes and off-road model cars. Consequently we are well served with low risk to battery packs
• I am a novice right now. Trial and error.
• Dewit!
• Do it, you will never look back. And remember, you can't really run more than a couple of locos at a time, so you do not need a controller for each loco.
• Do it saves track cleaning and maintaining stable power supply
• They are convenient as an entry point and ideal if you are on a budget. If you lack time for long running sessions then they are available instantly. They also require little maintenance if you don't have a dedicated workspace.
• My 5” battery loco easily pull 14 passengers on 5 trucks- 2 driving trucks - 1 driver 1 - guard and 3 passenger trucks- 12 passengers
• Do it.
• If you still want to use track power, a battery loco is great to pull round a track cleaning wagon, this means I can still enjoy my LGB locos as well as my growing collection of kit built locos.
• If you don't have enough experience with battery powered locos, buy first a factory made one.
• They have their place. Go for it.
• Just don’t hesitate. It’s the obvious choice for a garden railway
• Do it! Much easier and better than live steam which we gave up
• You won’t look back
• Good move.
• Research. Lots of. And ask questions
• Do it your way
• Just depends on pocket & skills level
• Don't underestimate complexity vis a vis, not plug & play
• Track power and living at the seaside are not compatible
• Get the best from your railway and have instant running with a battery loco
• Take your time. Do your homework. Experiment with a small kitbuilt loco first to gain confidence
• Think about what your preferred running style might be - and work to that. There’s no one-size-fits-all and what works for someone else might be challenging for you. Take the time to talk to people who have experience, and try to get different viewpoints before making a decision. The hobby is incredibly varied and that’s one of the great things about it!
• It’s a good idea
• Enjoy it and do what you love
• It's simple and easy.
• DO IT !

Advice on battery choice

• stick with nimh, lipo are still to unstable when charging on board
• Not not be afraid of lithium, safe if correctly handled
• Look around and don’t pay through the nose for a bespoke batt pack unless you have to.
• NiMh is safe, reliable and perfectly adequate
• LiPo every time
• Rechargeable is more environmentally friendly.
• Place battery in trailing car if possible
• Use Lithium ion packs and ensure it has a built in re-settable circuit breaker built in.
• Make sure you get [batteries] from a reliable source and have internal resettable circuit breaker.
• I think NiMH cells give a good balance for energy density, cost and simple charging requirements for rail use.
• Removable batteries if you can do it. That way you can use the cheaper, lower-capacity packs and just swap them out when they go flat. No need for a pack for every loco, just one for every loco you want to run at the same time, plus a spare or three.

Advice on construction or conversion of battery locos

• Start with a small kit-built loco with non rechargeable batteries and then start making your own when you gain confidence
• Build them heavy
• Always put in some sort of fuse or overload trip and make sure batteries can be removed easily.
• Have your batteries on board. Don't do a trailing car.
• Make sure batteries are reasonably easy to access for eventual replacement
• always make sure you can change your battery pack, even if they are rechargeable.
• Install a fuse close to the battery pack
• Choose the right wire diameter, keep wiring tidy, keep wiring documented.
• We all have different requirements - a small battery loco is great for hauling a few skips or slate wagons when things are quiet, or when wanting to quickly run something. Best advice is to start with a kit, or a chassis and build your own body on top; I did that and have further improved that loco over time and used the lessons learnt when building my own battery locos
• make your batteries easy removable.
• Research first, talk to others, stay with standard commercial readily available batteries, a good battery charger that will cycle and detect faults.
• Learn to solder. Also consider what you plan to have it do before choosing which motor to put into it.
• Read conversion threads in GSC

Advice on battery management

• Always recharge after use
• They run longer then you might believe
• Remember to charge/ have spare batteries and to take them with the loco
• If starting over, I would make the batteries rechargeable from the track. That way you can just have live sections of track to park on and your engines will always be ready to go. I initially went with removable batteries for expediency in getting engines running, and I'm now intending to retrofit an on-board track powered charger for convenience.
• Buy a decent charger with plenty of options for different voltage/amperage otherwise you end up with a draw full of single type ones. Store lead acid fully charged.
• Ensure that your charging is safe and done correctly
• Battery powered seem to have less power

Advice on control systems

• Give it a try. Very easy with RailPro
• Avoid Bluetooth control!
• If you're handy with R/C electronics and don't mind some tinkering, cheap airplane radios are often a better option than purpose-built train control systems.
• Use LocoRemote control (just as satisfied customer)
• Having used Deltang for many years. I cannot now recommend them and have found Fosworks much much better.
• Get it ASAP Buy a Piko RC starter set and see if you like it. You could then pay to have some track powered locos converted to RC, costly, or start tinkering with it yourself. Piko RC units can be bought cheaply and are relatively easy for beginners to install. Riks blog website and articles are G8
• Start with a ready made one even if it seems expensive. Piko Roncali Circus starter set is ideal. Old Playmobil needs a bit of tech knowledge. Lionel RTP see below.

And finally, respondents were asked if there was anything else they wanted to add.

• Battery locos can be just as impressive as steam powered locos.
• All of my locos have either 8 or 10 NiMH cells, ranging from 1500mah to 3000mah capacity. This size battery pack has been more than enough capacity for typical service.
• 45 mm gauge gives you the widest possibility of choice of prototype as you interests may change/develop
• I am a bodgeller, my locos use a variety of commercial bits, parts from kits and recycled stuff so not strictly scratch built. Only 1 a converted LGB pump cart has batteries in a trailer
• Don’t let people put you off
• Have fun!
• Battery locos are often be far more realistic than the majority of commercial steam locos, and far, far cheaper
• I just like battery locos.
• I have batteries in liv steam locos for R/C. All use NiMh batteries. Two use loose cells that I can remove and charge externally as required. One has a home-built pack that I can remove and charge externally, but this requires a different charger to the loose cells. I have a multi-chemistry charger that could easily charge the loose cells if I made the right wiring harness, but it's easier to use a cheap, ready-made charger specific to NiMh batteries for this.
• I've built and modified a few and my preferred option is RC battery powered
• Basic locos with fwd/rev are great for just running something
• My battery locos are in addition to steam locos, sometimes its nice just to be able to run a quick train without the faff of raising steam.
• I have too many locos and it wouldn't make financial sense to convert all to battery
• My batteries are 8-cell NiMH airsoft packs, semi-permanently mounted inside the tenders of my steam locos. I charge them via a socket installed in the tender deck.
• But have other forms of power - gas or coal steam powered locos
• There is plenty of information on the web or join a club, association, forum or Facebook group to ask specific questions
• Have fun playing trains, no matter what source of power.
• Using battery allows you to use cheaper track you dont have to keep clean.
• My first experience with 16mill was with Triang Big Big as a child, so theres a bit of nostalgia in there too!
• Enjoy!
• As of this writing (May 7, 2022) the LocoRemote website says they have closed shop for a while and paused sales. They are still providing support. More info at http://www.locoremote.co.uk/
• Ignore the critics - they don't know what they are talking about!
• Power tool batteries are a dime a dozen and there are bargains out there! Also don’t give up on track power because of hearsay.
• Nice survey. I am surprised that the interim results show Fosworks at only 1%. My "inside information" suggests that they are now selling at least as many as Deltang.
• Errors are a learning exercise. Use it as such. Have fun. Try again.
• To be honest, I found I spent a lot of time referring to your (very informative) blog site whilst setting up my locos with deltang RC and MLS sound cards
• I’d like more battery power but I’m clueless on converting. Would love if it someone set up a business converting where you could send to etc
• Deltang - learn to program, most helpful.
• Once you enter the "Dark Side", you won't go back !
• I still will not use LiPo batteries or the like. I do not trust myself to handle them correctly.
• Would love to have a solar powered (battery) loco.
• I also use wi-fi to control everything else. Far cheaper.
• Read Rik's blog. I have learnt so much from him. It has revolutionised my railway modelling. Thank you.
• Look at BlueRailTrains.com. Excellent control for battery power.
• I run two 3-hour back-to-back op session each month. My 34mAh batteries require but one charge for the whole weekend.
• get my batteries from Strikalite, very long lasting.
• Battery checks, servicing and recharging can all be done indoors and off- layout (garden) I keep a spreadsheet for all Locos and an individual logsheet for each Loco, recording the date last run, the recharge amp-hours after that run and lubrication events.
• Lionel Ready to play is an odd track gauge but great for kids and grown ups. I have several as well as my 45mm gauge sets.

Many thanks to all those who took the time to fill in the survey and to add a range of really helpful and insightful comments.