Further wagon & tippler progress

I'm getting very close to full wagon production. After half a dozen test prints with minor design tweaks in between, I've assembled a full wagon complete with couplings so I can do some test running. It will need some weight to be added but there's space enough underneath for a bit of lead sheet.

I'm still not sure if the quality will be good enough. I've learnt a lot about the settings needed and it does seem the original Bambu PLA gives slightly better production than the Sunlu I also bought. Adding a filament dryer from which the filament can be fed directly seems to have helped enormously as well as adding brims to the corners of small elements in Bambu Studio. I'd prefer not resort to resin printing as the PLA is much more robust than most resin prints I've seen. The only part which doesn't print successfully is the brake lever so I'll probably use brass etches for these.

I've also progressed the design of the tippler. Solidworks Xdesign enables me to simulate how the shute can be lowered and wagon on the tippler frame will tip the clay into the SG wagons. This has only been done manually by rotating the elements around pivots and checking by eye, i.e. I haven't used Xdesign to check whether elements actually hit each other which I know it is possible to do.

I did do a test print of the whole tippler frame which came out pretty badly but gave me enough info to realise it will not be strong enough as a 3D printed so I intend making it from brass sections, with perhaps the stairs 3D printed. It also made me realise the frame base will be about 10mm higher than designed. I altered the stairs in the design but I'm not going to bother redoing the tippler frame design as I've got enough info for the brass construction. The viaduct itself will be made from wood sections.

My plan is to haul wagons up the viaduct incline via a continuous chain which will have a link with a vertical pin every 20cm or so. The chain link and associated sprockets will be 3D printed. I intend the chain haulage, shute and tippler to all be operated manually from a crank and levers at the baseboard edge which will hopefully be fun for me and the grandchildren.

Wagon Progress

I've progressed quite well with my tipping wagon designs. I've settled on a design top hinged door with a fixed top plank which would help prevent bowing of the sides - on the prototype that is - it wouldn't really be a problem on the model. My first version had a real fixed top plank, however it quickly became clear that hinges that would be small enough to look prototypical would never be operationally reliable even if I could make them work at all. I had resigned myself to go back to the simple top hinged door which did work well with perhaps a top strap to prevent the prototype bowing. It's funny (or perhaps even sad) the things that can keep you awake in the dead of night, however it was then I realised that although it should look like the top plank was fixed, I could make the whole side tip anyway which I knew would work. When opening this would be largely hidden within the tippler anyway.

A tipping test of the body

A trial assembly

Another issue was the means to hold the tipping door shut. I was originally thinking of operational catches and some means to openin them within the tippler mechanism. Again I realised I could make these purely cosmetic and use other means to hold the door closed. I thought I would try using magnets which will hopefully have give just enough strength to prevent it opening when loaded but not when tipped. I designed pockets to take tiny 1mm dia x 2mm length magnets in the wagon base and 2mm dia x 1mm length in the side. Initial experiments suggest one pair of magnets may be enough, but it may be necessary to provide an additional force when tipping to make the side open reliably. This could be a stronger magnet within the tippler - much simpler than a mechanism to operate catch handles.

Note the tiny magnets in the base and bottom pocket of the side. I designed three holes to allow a single central pair or two either side. One pair looks to be sufficient.

One of the benefits of using Solidworks is the ability to visualise how the tippler could work including how the bits can tilt. I'm now fairly confident I have worked out the height it needs to be, the pivot location and the shute position. I can now proceed to fully design the tippler. In my history this would have been built in the 1930s and would have been constructed in metal with the viaduct made from wood. I also need to think about the means of hauling wagons up the incline. I think it may have to be some kind of cable but I'd like it to be automated.

The tippler schematic with tipping wagon platform and shute.

As an aside, real wagons on industrial railways look well used and abused often with bowed sides etc. The problem with printing from a design is they all come out exactly the same. I plan to have some variation in the design to represent different genres of wagons but wanted to introduce some distortion and wear and tear in the main body. It wasn't clear how to do this in Solidworks so I explored ways to distort the generated STL file. I'm not that familiar with Blender so it took me a while to work out how I could add some gentle distortion to the main body. I haven't tried printing these yet to see how it turns out. If successful I intend to do this from scratch for every wagon I print, some more than others, so each wagon will be unique. Coupled with variations in style it should give me a fleet of unique wagons.

 

Wagon Works

I've at last made a start on my long-planned wagon building program. I want the wagons to be distinctive to the rebuilt PLR, i.e. not copies of wagons used elsewhere. The most important aspect is the need for them to be tipped which I hope to do at least semi automatically. I want to try and build a tippler which has echoes of the original Pentewan tipplers with a pivoted section of track. My first thoughts are that it will be easier to automate if the opening side is full length and top hung. I'm not sure how prototypical this will be so would welcome thoughts from other learned modellers.

I'm designing the wagons using Solidworks for Makers. It had quite a steep learning curve however I'm now successfully producing components and assemblies. Test prints so far have been done on my Bambu A1 using a 02mm nozzle and basic PLA. The detail is pretty good and the PLA is remarkably strong. For full production I may get some parts printed in resin, although I'll need to be sure it will be strong enough.

Update 19/01/2025. After some very helpful feedback from fellow modellers on the O14 Group who pointed out the original design could easily bow in prototype practice and suggested a fixed top plank would be better. Here is a visualisation of a revised design:

Here are some pics of the (earlier) designs and prints:

Simple DC Controller

I only have two standard gauge locos at the moment - a GWR 55xx prairie which is so far just a rolling chassis and also a Heljan Class 42 Warship. Both of these are still DC but will be converted to DCC in due course. The Warship takes quite a lot of power - and the little old Gauge Master DC controller borrowed from my son's trainset would frequently cut out. 

I didn't want to splash out on a high-power DC controller, so though I'd try one of the cheap PWM motor controllers that are now readily available - I think driven by the rise in e-bikes etc. I bought this one which was a 20A 25KHZ PWM DC Motor Controller which cost a mere £17.99 from eBay:

I hooked it up to a 16v DC old laptop power supply that I also use for my NCE ProCab and tried it out. It works a treat. There doesn't seem to be any noticeable buzz etc from the locos and I think it will certainly serve well while I'm completing the SG.

Traverser installation

 The traverser has returned from its travels. I built it for O14 at ExPong 2014 and then gave it to David J as I had no use for it. He's had two house moves and now didn't need it, and as I could use it in the new config it has come to Devon.

It will be adapted to have two mixed gauge tracks. I've nearly finished the two curved spline roadbeds for SG and NG which connect to the traverser. The NG has a tight curve and ducks under the SG.

More Progress

The new board is ready and I'm now laying track. This time I've used dark gray EVA foam as an underlay rather than the hideous yellow stuff of old. Of course being so dark meant I had to use a white crayon to mark the centre lines and sleeper posistions. Previously I pre-stained the cut sleepers but this time I glued them down as bare wood and then painted them - with a dilute mix of black and burnt umber acrylic inks.

Track laying then progressed using my standard method with staple spikes and cosmetic fishplates etc.

I've decided to change my approach to ballast. Previously I used crushed cat litter and chinchilla dust glued down with dilute Copydex, however this has proved to very durable. I'm now trying crushed walnut shells in various grades.

Three grades of crushed walnut shells, grey dye and liquid latex

I wanted the ballast to be a light grey like the crushed cat litter (the PLR used a lot of clay-tip waste) but the dye didn't really work. I then retired an old kitchen mixer and added slightly diluted matt paint (old white primer slightly darkened with some black) whilst it was running. Then turned it out onto a cloth to dry. It has worked rather well.

The first batch (medium grade) is in the bag and the coarse and fine grades are drying

Once the track laying is complete I'm going to refresh any loose ballast on all of the older boards and get it wired up ready for operation.

A Selection of shots

 Here is a selection of shots taken before the move.

Ex L&B Manning Wardle hauls clay up to the exchange sidings

This originally had model track but it got removed about 20years ago after a change of plan. 

A down train passing the quarry.

And further down the line crossing the quarry road.

A up works train hauled by K1 (This was sold to the PLR by Beyer Peacock after repatriation and when the PLR finally closed in the 1960s it went to the NRM). 

Progress at last in the new home

When the loft was completed last year it was far too hot to do anything apart from get the boards up there. I spent a long time trying to work out the optimum config. It was clear the two main sections would need to be separated and came up with a design that I thought would work but would have involved a lot of extra hidden track. I built the staging for the spiral/quarry and then realised it wouldn't work so decided to rotate it 90degrees. With temporary extra bracing added I slowly shoved it round from underneath. I got it about half way round and realised that was a far better position. 

With a little bit of shifting to-and-fro I've now completed the staging for the exchange sidings and positioned all the current boards. There will be one new board required  of about 5ft long which needs to accommodate a  6 inch change of datum level (I'm used to doing that). Track will be laid on raised trackbeds built the J H Ahern way (still be best book I've got).

The fiddle yard will be beyond the lower tunnel in a similar config as in the last house. The traverser built for ExPong is going to come to Devon too now David J no longer needs it. There is even the potential to join it up to get a continuous run of close on 90ft and then simply watch the trains go round. The grandchildren may get to race their engines (which I've promised to build).

Some photos from today:

Note the gap for the new board in the background.

The fiddle yard will be behind me. 

On the move

 The crates have gone into the lorry today. It may be some time before I see them again as we still haven't exchanged on our Teignmouth house.

PLR Ready for transit

It took several days to separate all the boards and get them downstairs and then dismantle and clear all the staging and workbench etc. Here are some photos of the progress.

All the boards downstairs into the conservatory:

Notice the odd shapes and height of some of the boards - this is certainly not a railway built on a flat piece of board!

Crated up ready for transit:

There are 4 crates each with several boards within made using the wood from the loft staging and with the high hill as a separate piece. The crates are designed to be carried by two people and stack for transit. I've used pallet cling wrap on the scenic boards to keep them clean as they could be stored for some months before the new log cabin home is built. The removal people frowned when they saw it all (they had been warned).

The clear loft:

What a nice railway room it would make! However, I don't think the new owners are that minded. This room was actually one of the reasons we (well me) wanted to buy the house all those years ago. It didn't have the floor boards nor insulation then. Note the water tank that dictated the big hill and the track spiral which tunnelled down behind it.

So Devon next!