lucas

A few people have asked about the 3D model I made, so I've attached them both here and in the original post. The .f3d file is the design file for Fusion 360 and the .stl is the finished model if anyone wants to print it. Feel free to use them however you want as long as you give appropriate credit; i.e. don't pass it off as your own. c-class-body.f3dc-class-body.stl

As long as I can get a little use out of mine before before it gets usurped by a RTR version I'm happy

I recently bought a sound chip for my Murphy Bachmann 181 from Roads And Rails. He emailed me after I had put in my order to ask whether I had the old Bachmann or the new Murphy version, so there must be some difference. I haven't gotten around to fitting it yet so I can't give you the full review, but I might try to tackle it this weekend.

Class 15 is probably the closest BR loco, but it's still 1' 6" (6mm to scale) longer between bogie centres and 6" (2mm) longer bogie wheelbase. I had been using this list http://www.clag.org.uk/wheelbase.html for comparing dimensions. For reference a C Class has 21' 0" between bogie centres, 8' 0" bogie wheelbase, and 3' 2" wheel diameter. I'm hoping to keep things within a mm or 2 which doesn't really seem to be possible with anything that ran in Britain. Unless something perfect comes along I might just end up building my own chassis anyway. Even if not out of necessity, as a challenge to myself. I've always been the kind of modeller that likes building models, not necessarily just playing with finished models.

I figured a 121 would probably be closer, but I hadn't been able to find the exact dimensions. I had always assumed the bogie wheelbase would be the same 8' 1½" as the 141/181, not that you would see the difference. I might keep an eye out for a damaged 121 I wouldn't feel too guilty about cutting up

Here it is sitting on top of my Murphy/Bachmann 181. The distance between the bogie pivots and the overall length are each too long, so it would need a ~10mm slice cut out of the middle. The bogie wheelbase and wheel diameters are both <1mm off, so it could work. But then again they are a bit of a pain to regauge (I've been putting off regauging this 181 for a while).

This is good information, thank you John! To be honest I'd been looking mainly at UK models for a donor chassis without really considering much else. I reckon I'll need to take a closer look further afield before deciding what to do.

At the moment I'm thinking unlined green. But I am the kind of person that changes my mind a lot, so we'll see

I'm not entirely sure yet. Nothing RTR seems to have the same dimensions, plus I'll be building to 21mm gauge which further complicates things. I might well end up having to design my own chassis if I can't avoid it.

I’ve been wanting to build a C class loco for a while now. I was originally planning to use the Silver Fox kit, but there are a few aspects of the kit that I wasn’t super happy with. The main issue for me was the kit represents the later reengined B201 class, not the original Crossley-engined locos I wanted to model. The roof detail in particular changed a lot during the conversion; the existing vents were chopped up and repositioned to suit the new GM engines, the exhausts were completely different, and a much larger cooling fan was installed. The side radiator grilles were also much larger on the reengined locos, but interestingly the kit does use the smaller Crossley grilles here. I figured if I was going to end up cutting up the kit to get it looking how I want, I might as well just start off with a clean slate and build my own. A couple weeks ago I started working on a 3D print of the body shell. My little old FDM printer has neither the resolution nor the willpower to actually print any detailed parts, but I figured it could give a decent attempt at getting the basic shape dialled in. This isn’t just going to be one of those ‘scratch builds’ where the whole thing is just 3D printed in one go, I swear. I forgot to take a picture of the finished print, but here it is after the first round of sanding. I printed in red because I’m modelling Iarnród Chorcaí after the People’s Republic declared independence because I just had a bunch of red filament lying around. Here is the final revision behind an earlier draft. I made a slight tweak to the angle of the upper section of the cab with the windshields. There is only a fraction of difference between them, but the earlier print just looked a little off, to my eyes at least. As amazing as the CAD tools are, it’s a lot easier to see if things look right on a physical object. While I got most of the main dimensions from the C class drawings in the resources section, things like the curvature and angle of the cab ends were done by measuring photographs of the prototype from different angles and adjusting as necessary until it looks right. I think I got it pretty close, even if I do say so myself. To fill in between the layer lines on the 3D print I use Polyfilla (yes, the stuff you use to repair holes in walls) thinned with a few drops of water. I brushed on a few layers and sanded back down to give a smooth finish. I will still need to give it a coat of filler primer when it comes time to paint it, but has smoothed out most of the bigger imperfections from the printing process. The two red rectangles you might notice on the side are slightly recessed to align the air intake vents. I masked them off so that I wouldn’t fill them in which is why they’re still a slightly brighter shade of red. I actually haven’t decided how I will make the vents themselves. I will likely need some etched parts for the roof and the chassis, so I might design some etched for these too. I did pick up Studio Scale Models’ detailing kit for the Silver Fox kit, so I already have etches for most of the other grilles. I’m hoping to start work on the underframe this weekend, but I figured I’d share my progress so far. EDIT: A few people have asked about the 3D model I made, so here they are. The .f3d file is the design file for Fusion 360 and the .stl is the finished model if anyone wants to print it. Feel free to use them however you want, as long as you give appropriate credit; i.e. don't pass it off as your own. c-class-body.stlc-class-body.f3d

I would also put my vote for a G class. I've always found it to be an attractive prototype, but it would easily get lost among larger locos in a OO layout. It would be well suited to a larger scale shunting layout IMO, just like the Accurascale O gauge Ruston from a while ago.

Yes, you're reading it right, one wire to each side of the motor. A capacitor doesn't allow current to flow through it, so it won't short. It only stores a small amount of current which it feeds back to the motor when voltage from the rails disappears.

You typically don't pay much VAT on second hand things in the first place. The idea is that VAT was already paid when it was sold the first time, so you only pay VAT on Rails' profit margin when they're reselling it. At least that's how it works in Ireland, I assume it's similar in the UK. It's probably too complicated for Rails to deduct VAT from just their margin, or maybe they don't want to reveal exactly what their margin is

I cranked up the brightness and contrast and you can sort-of see there is a wheel there alright.

I hadn't come across this one, looks interesting! Yes, I know that. I just happened to have a few lengths of unused flexi-track already on hand

Thank you! In future I'd like to find a way of making these jigs based on track plans from Templot. That would save me a lot of work designing the point geometry, but I'm not sure how easy that would be.

I have intermittently dabbled in railway modelling for the last 15 or so years, but seeing my dad's (nearly) complete OO9/HOe Dutch steam tramway has given me the itch to do some more modelling of my own. Of course having grown up in Cork I have very little nostalgia or even knowledge of Dutch trains, so I thought I should have a go at some Irish trains instead. Unfortunately I don't really have the space for proper layout in my current apartment, but I'm set to be moving to a bigger house in around a year or so I figured I'd get started with some rolling stock in anticipation. And just to make things difficult for myself I wanted to have a go at modelling with 21mm gauge, which means I'll need a short stretch of 21mm track on which to build and test those models. Having read about a few different methods of building track, it always seemed weird to me that track is built sleepers first with the rails fixed on top. In my engineer brain it always seemed more logical for the rails to be held in place with the correct gauge (since that is the important dimension) before the sleepers are attached to the bottom. Now admittedly I am an electronic engineer, so my engineer brain could easily be very wrong with something like this. But I wanted to give it a try anyway. First I 3D printed a jig to hold the rail in place. Actually, I printed 5 different jigs because it took a while to get the dimensions just right. It needed to hold the rail snugly at the correct gauge, and as it turns out my printer just isn't that accurate. Here it is holding the rail in place. I'm using regular Peco code 75 track which has been destroyed disassembled for this experiment. In the background you can also see some of the failed prototype jigs. Actually I think the one holding the rail in this photo was also replaced by another revision because the track gauge was a little off. The final revision jig holding the chairs in place. These are incredibly fiddly to get onto the rail, but I reckon when I get to building a full layout I'll opt for bullhead rail so it might be different. Or I'll opt for another track building method, I'm not sure yet. I had a friend with a laser cutter cut some sleepers out of thin wood. I couldn't find good dimensions for the sleeper width and spacing so I eyeballed it. These are 3.5mm wide with 10mm centre-to-centre spacing, and look pretty good to my eyes anyway. The sleepers were glued to the chairs with poly cement, which in my testing creates a good enough bond between plastic and wood. It also doesn't stick to the PLA plastic of the 3D printer, so no fear of accidentally gluing the track to the jig. Using a heavy book to hold the sleepers in place while the poly cement dried. The first set of sleepers after the glue has set. I placed the last sleeper of the previous set in the jig to align the next set of chairs and keep the spacing consistent. Checking the track gauge. 21.01mm is what I call close enough. The finished length of track, glued into place to a scrap piece of chipboard. Close up of the track. You can see one of the sleepers is not quite perfectly aligned. Since they are not glued onto the rail itself they do have a tendency to move around a little bit, but it's not noticeable enough to be a problem. Now this is a simple straight piece of track, you might be wondering how would this work for curves, never mind points. For curves it should be relatively simple since the sleepers can slide around along the rail it can be used like a piece of flexi-track and bent to shape. For points on the other hand... that is a very good question. Since I won't need to make any for another while I guess we'll cross that bridge when we get to it. Another potential pitfall of this technique is speed. While it does take some time to thread the chairs onto the rail and align everything, I was mainly limited by the drying time of the poly cement I used. This meant I could effectively only do 8 sleepers in a session. This could be alleviated by using a larger jig, or with multiple jigs doing multiple lengths of track in parallel. Anyway, overall I'm very happy with the result. Now it's time to put this test track to use regauging, modifying, and scratch building some trains. ~Lucas

Hi All, Looking for a set of these if anyone's selling ~Lucas