Australian steam locos

[Gumboots]

Was just thinking of things and taking a bit of a look around. It turns out that Garratts already exist. Sort of.

The Crocodile Tears and Bipolar Disorder electric suppositories are basically Garratts, in terms of how they are put together. They both have large, identical-but-mirrored, trucks attached to each end of a central body unit that hangs between the trucks, or would on the real locos. What happens in RRT3 is slightly different (because of the way track attachment points, etc work) but in terms of major components and geometry, those two electrified abominations that exist only to pollute the game and molest innocent kittens are the same as Garratts.

Of course Garratts are much better, because they go choof-choof-choof and this makes them superior, but it looks like any Garratt modelled in RRT3 will behave much like the aforementioned mobile MIG welders.

So, I did some brief testing with very lumpy and windy track. They're a bit funny sometimes, but then so are the game's big Mallets, so really not any worse over extremely curved track (vertical or sideways). Short version: should be acceptable most of the time, and provide some *** moments and laughs some of the time.

[Gumboots]

While you're working on rear trucks, can you do something about the rear truck of J3a Hudson? Some work really did go into that one, except the rear truck stayed a 2 wheeler. Or maybe you could post a guide on conversions like this and I can commit to doing it myself. I have been working on and off with codes, but I'm still very much in the trial and error/experimentation phase.

Was just thinking about this request, as it has occurred to me that at some point somebody should fix some of the 1.06 locomotives. As currently modelled, it's really just the default PopTop H10 Mikado with a different paint job and some tweaking of wheel sizes and spacings. It's quite effective, but could easily be improved.

The NYC Hudson model actually does have 4 wheels on the rear truck. It's funny how it's been done though. Instead of adding 2 extra bogies to the rear truck, what the person who made it did was to take the two superfluous driving wheels of the default H10 model and shrink them to represent the extra rear truck bogies. This works well enough for game purposes, but just seems a bit amusing.

Since it's based on the default H10, and since I know that file backwards by now and have already hacked it to death, I'd be happy to help anyone who wants to improve the J1 model. One obvious step would be to do what I did with the Berkshire, and split the tender out to a file of its own so the text shows the right way around on both sides. That's already mapped and ready to go.

Another obvious step would be to start with the PopTop H10 A skin instead of using the skins tools, to get much better gfx resolution on the finished model. At the moment it's effectively starting with a B skin instead of an A, and the difference is really obvious. Since it looks like all that's been done is a basic hue/saturation change on the default gfx, doing the skins over again should be very easy.

[Gumboots]

Hey I've just been playing around with Blender a bit. Since the export script is available now I'm a lot more enthusiastic about modelling. I'm going to get back to finishing off the Schools class, but just for fun I quickly roughed several of the other locos I had been thinking of building. These are accurate as far as they go, but are obviously just basic starting points, and not anywhere near finished. Doing all of these models to this stage only took about 6 hours in total, if that.

First one is the infamous monster Garratt, of course.

#AD60_Garratt_beginning.jpg (21.04 KiB) Viewed 8766 times

Second one is a NSWGR C32, an old express 4-6-0 that was in use until the end of steam. The first one built was in service for 80 years and covered just over 2,600,000 miles.

#C32_beginning.jpg (31.59 KiB) Viewed 8766 times

This is a base model for the D57 4-8-2.

#D57_Lizzie_beginning.jpg (29.01 KiB) Viewed 8766 times

And hey, streamliners. We gotta get some more streamliners. This is the Victorian Class S, a large 3 cylinder Pacific.

Top_right_roughed_out.jpg (37.54 KiB) Viewed 8766 times

[RulerofRails]

Look great! The Mallett will probably be the hardest to make but will be great for African scenarios also. I always loved seeing pics/video of the Malletts running on narrow gauge. The streamliner will be good too. Wish there was a way to adjust passenger appeal via the editor. Set all freights/mixed trains to ugly making dedicated express trains more valuable economically in a particular game.

[Gumboots]

That's Garratt. The game already has Mallets. You're getting you're Garratts mixed up with your Mallets.

I was thinking of setting passenger appeal to ugly for the freight Garratts anyway. Same for the D53 2-8-0 and D57 4-8-2, since freight was all they were ever used for. If I do a couple of express Garratts, like the TGR Class M or that Algerian beastie, they'd obviously get a suitable passenger appeal rating.

Garratts aren't actually any more difficult to make, apart from some extra work for skinning extra bits. The front and rear units are usually identical, and the middle unit is usually simple in form, so all up it's not too bad. The sheer length of the bigger ones might be a bit messy on RT3 corners and grade changes, but much the same applies to the big Mallets we already have. I'm thinking it'd be a good idea to whip up a basic test model (mainly wheels, with a couple of boxes to tie them together) just to check out the basics of Garratt behaviour when running live in the game. I might do that this week, since modelling and coding to that level is quick and easy.

[Gumboots]

Here ya go: the game's first Garratt.

It's still missing some bits and pieces, and a proper skin, but I was keen to finally check the basics out, live in-game. This is the model I was talking about. It's all in proportion, but has only the wheels and some basic body/truck components to give the basic feel of the thing.

Geometry still needs a bit of work. There's no problem getting it to turn into corners, but I'll have to spend a bit of time sorting the best positions for track attachment points and truck attachment points (not the same thing) to get the best looking behaviour around a range of easy and tight corners. It's already ok most of the time, but I think it can be made better.

One fault it does have is shared by the game's big Mallets (Big Boy, Challenger, N&W Y6, etc) and relates to changes in grade. This is that the trucks, and the wheels attached to the trucks, stay roughly in line with the main body of the loco even over grade changes. This means the front wheels tend to dive into bridge on ramps, for example, and stick up in the air a bit over crests. I don't think this fault can be sorted within the game's coding limits, since it seems to be a hard coded behaviour of trucks.

So, anyone wanting large Garratts and/or double or triple cargo cars will probably have to put up with some odd looking tricks over sudden grade changes. Gradual changes in grade won't show the effect too badly, but if your track is lumpy you'll really see it. Call it a good incentive to not lay lumpy track.

I'll be getting back to finishing the Schools class, and will leaving the Garratt and multiple cargo cars alone for a while. If anyone wants to play around with the basic Garratt while they're waiting for the final version, let me know and I'll attach a packed version.

Anyway, pix attached.

Basic_testing_1.jpg (77.73 KiB) Viewed 8731 times

Basic_testing_2.jpg (83.33 KiB) Viewed 8731 times

[Tomix]

Are you planning to model actual wheels or use flat planes with a texture over them? Also, how are you able to define the start and end of a loco? As well as the smoke and lights?

[Gumboots]

I was planning to use flat planes with alpha masking to do the spokes and rims. That's how all the default RT3 models are done, and it gives a much lower vertex/face count compared to actually modelling the whole wheel. I could model the wheels in 3D easily enough, but I'm not sure it's a good idea.

The AD60's drivers have 14 spokes, which means a minimum of 42 vertices and 42 tris just for the most basic 3D model of the spokes. If you want any taper in the spokes, up that to 63 vertices and 84 tris. Then you'd have to add the rim, so double that count. Call it 100 verts and 150 tris, per wheel, just as a ballpark figure. The AD60 has 16 of them, so 1600 verts and 2400 tris just for the drivers, without any of the leading and trailing bogies, and without the rest of the locomotive. That's the entire budget blown just on drivewheels.

OTOH, if I do it with planes and alpha the figure drops to 16 verts and and 8 tris per wheel, even if I use as many as four layers (some default locos use up to four layers).

The start and end of the loco are defined in the LengthPoint.3dp file. Smoke and steam have .3dp's called AD60_Garratt_L_BlackSmokeFatC1.3dp, AD60_Garratt_L_TSteamC1.3dp and AD60_Garratt_L_TSteamC2.3dp. These are really simple files that just define one or two points. The game's animation files take it from there.

Incidentally, although the default locos only have one steam file each, with the two points usually set to be just behind the cylinders, I found that you can add as many steam files as you like. So if you want steam coming out everywhere, you can do that just by adding more .3dp's and defining more points. It's of limited benefit though because you really only get the full steaming effect when the train is stopped, in which case the loco is translucent anyway. As soon as the loco starts moving, the steam quickly drops right off. However, you can steam up the entire station if you want to.

Same with smoke. You can make it come out anywhere you want. The only catch is that it will always start vertically from whatever point you define.

I posted about how lights files work here: viewtopic.php?f=67&t=3394&start=60#p35751

[Tomix]

So are these points defined by vertices, or are they different sort of points? Would you also mind posting your track model? It would be handy to make sure everything is in scale.

[Gumboots]

Yup, they're just normal x/y/z verts. Like for a smoke file there will be just one vert defined. This is in the centre of the funnel in plan view, and usually set down by about one unit below the top of the funnel in profile view.

Not sure what you mean by track model. If you mean RT3's default tracks, they work out at a scale of 10" per RT3 unit. That's the scale I've been working to for my modelling (the default models are all over the place for scale). So taking the AD60's 55" drivers, they're modelled at 5.5 units diameter.

[Tomix]

By track model I meant the track that you've been using in your blender scenes.

For wheels, how do you tell the game where which wheel and rod goes? I vaguely remember reading on this forum that the game automatically animates each wheel/rod.

[Gumboots]

Oh you mean the map? It's just a sandbox version of my Royal Tour map (same base map as default SE Australia). I simply added a few basic lines to it to run things on. Also has a particularly nasty set of tight S bends snaking across the plain between Bobadah and Bourke, just to give the harshest testing of train geometry on corners.

For wheels, read the first page of this thread: viewtopic.php?f=67&t=3394#p34126

For connecting rods and stuff: viewtopic.php?f=67&t=3394&start=75#p35829

Edit: Ok, not the map. I figured out what you mean. You want the .blend for the base plane, ballast, rails, etc. Ok, will zip it up and attach it.

[Gumboots]

Ok, attached.

[Tomix]

Thanks for the info and track. I'll have to go experiment now.

[RulerofRails]

That's Garratt. The game already has Mallets. You're getting you're Garratts mixed up with your Mallets.

Yep. Hasty mistake. Had couple of seconds to write that and somehow the brain misfired. The Garratts look much more utilitarian than the Mallets. I imagine it's a little difficult to see the track right in front of these engines. One of the coolest types of engines ever in my opinion.

[thietavu]

A Garratt for RRT3... Wonderful!! :)

[Gumboots]

This is starting to get off the track of Australian locos but anyway...

I was looking into various Garratts, from the perspective of getting a useful minimum roster together to cover the period from their introduction to the end of steam. With the way RT3 is coded, ideally you'd have gruntier ones coming in after 1950 to deal with the heavier cargoes introduced then. There's a problem here. The gruntier ones are pre-WW2. The ones built after the war were less grunty.

The gruntiest freight beast Garratt ever was the SAR Class GL, which at the usual 85% rating for tractive effort came in at a whopping 89,137 lbs of grunt. This makes the AD60 look a bit on the weak side, much as I hate to admit it. The GL would also be easier to deal with in-game, being 16 feet shorter than the AD60.

OTOH the AD60 was faster by a fair margin, being capable of over 60 mph compared to the GL's maximum speed of around 45 mph. That still doesn't help it much, because the fastest express Garratts were also pre-WW2. There's the French/Algerian 231-132 BT which managed to go downhill at 82 mph once, which is the official articulated record, and there's the Sao Paulo Railway R2 (another double Pacific) which regularly ran at over 70 mph. Both of these cream the AD60 for top speed and would also have more passenger appeal. The Algerian one even has a higher rated tractive effort than the AD60, and the SPR R2 isn't far behind. Both of these are comparable in tractive effort and top speed with the NYC L series Mountains. Again, being shorter than the AD60 would make both them easier to get behaving in-game.

So at the moment, the only way I can think of getting gruntier freight beasts after WW2 is to double-head the AD60, which was on the agenda anyway since they were used like that. That leaves express, and there aren't really any suitable candidates there if we want extra grunt in a specific express Garratt. I don't really like the idea of double-heading express Garratts, and I don't really like the idea of going backwards for express. About the only way around it that I can see is to build my own express Garratt for after WW2.

Anyway the SAR Class GL and the SPR Class R2 look like ones we should definitely have. I have good drawings for both, which is always a bonus. I roughed out the R2 last night. It's a good looking thing for a Garratt. Originally built as a double Prairie (Class R1), then converted to double Pacific (Class R2). I assume they found the leading bogie better for the speeds they were running. I have drawing for both configurations, but I think it makes sense to do it as an R2.

SPR_Class_R2_basics.jpg (37.48 KiB) Viewed 9249 times

[Gumboots]

SAR Class GL roughed out.

(It really is awesome having halfway decent drawings to work from)

SAR_Class_GL_basics.jpg (29 KiB) Viewed 9238 times

[Gumboots]

Hey I just found out some unusual things about the Class GL. This is going off the original works drawings, so isn't a mistake.

So usually, in profile view the centreline of the pistons/cylinders is in line with the axle of the driving wheels. So if the cylinders are raised above the axles, the cylinders will be angled to keep a straight line through to the axles. Examples are locomotives like the Black 5 (the real one, not the 1.06 mutant) etc, where the effect is clearly visible.

The Class GL is different. The centreline of the cylinders and pistons is 2 inches above the axles. Despite this, the cylinder/piston central axis is still exactly horizontal, meaning it's out of line with the axle. I've never seen this on any other locomotive plans. Beyer-Peacock must have figured that with the connecting rod being so long and the angle so slight, it wasn't worth worrying about. It certainly seemed to work just fine in practice, since the class had a long and successful service life.

However, it does have the effect of making the drivetrain impossible to model accurately in RT3, because RT3 can't deal with that geometry. Fortunately this probably won't matter, since the discrepancy is only very small, so it should still look ok in the game. The piston will slice across the cylinder diagonally, but only on a very shallow angle.

SAR_Class_GL_drivetrain.jpg (83.34 KiB) Viewed 9231 times

Ok, so that's the first unusual thing. The second one is that unlike most Garratts, the GL has uneven spacing on the drivewheels. The first, second and third driving axles are evenly spaced, but the gap to the fourth axle is larger. This seems to be to provide extra room for the pivot bearings for the front and rear units. Come to think of it, I would have expected a Belpaire firebox too, but the GL has a roundtop firebox. It's generally a rather odd class.

Anyway, have fiddled with it a bit more.

SAR_Class_GL_update.jpg (42.5 KiB) Viewed 9231 times

[Gumboots]

Since this has pretty much turned into a catch-all thread for all sorts of stuff, here's some bits and pieces I've been playing with for Blender practice recently. Most of them are Australian locos, but not all of them. I'm getting pretty good at making Belpaire fireboxes, among other things.

So I made some more progress on the Victorian S Class streamliner. Tweaked the loco some, made a tender for it, and roughed out a consist as well. This is one where I'd really want custom express cars. It bugs me when the pax haulage always has "Pennsylvania" or whatever on it in any country, and cargo cars are very simple to model and skin compared to locomotives (which aint).

So the consist here is to scale, with the mail car (first behind the tender) being about ten feet shorter than the pax cars. The last car on the end is what was called a "parlor car" on the Spirit of Progress trains, which is the same thing as observation cars on other trains. Like a lot of those, the Spirit of Progress parlor car had the round tail that was trendy at the time. It's the same length as the 6 standard pax cars shown in the picture. For RT3 purposes it'd be the dining car.

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Have also done some more on the D53. I want this one finished sometime because it's a good moderate-sized 2-8-0 for the World category. It's representative of a lot of them in early 1900's, when superheating first became available, and would make a good one to take over from the old Connie when that gets put out to pasture in 1912.

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Then there's the C32 4-6-0, another good World category option. I've done some more work to that too. Most of these were built as the last of the pre-superheater era, but the last one came superheated from the factory. It worked so well that the rest were converted in the early 1900's. I could easily do both versions: the original 1892 saturated and the 1911+ superheated, since the only real difference is a longer smokebox on the latter (that's the version shown in the screenshot).

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There has also been progress on the D57 4-8-2 model. Added a fair bit of detailing and made a tender for it. These were pretty much the NSW equivalent of an A1 Berkshire, were from the same period, and had similar performance AFAIK. NSWGR had easy access to plenty of high grade steam coal at the time, so huge fireboxes weren't needed to keep steam up. RT3 is short of Mountains at the moment, so another one would be good.