Australian steam locos

[bombardiere]

Great work with Garratts. I have not yet run it, but I certainly will.

Yes, we know that RRT3 does odd things. I think that the game is so old that at the time it was not possible to buy 3D engine for a program. So we are stuck with whater physical model the programmer came up with.

[Gumboots]

Ok, Garratts. We are going to want them, so I should test some ideas for making the big ones behave. Just as a break from other things, I had a quick play around with the AD60 Garratt model again. It's now up to this stage:

AD60_Garratt_1.jpg

This has hardly any UV mapping yet, but is on track for detailing and poly count. The catches with big Garratts are, as mentioned before, skinning them with a reasonable level of detail and getting them to behave over undulating track. The really long cargo cars aren't too bad over undulating track, because they have the loco in front of them and other cars behind them to take your eye off some of their dodgier behaviour. The locomotive is right out front, so if that looks dodgey over undulating track it's really in your face.

That is what initially led me to think the AD60 would not be workable. That then led to thinking that it might work if done as a loco + "tender", to shorten the loco wheelbase enough to make it behave, but I haven't tested that yet. I'm going to test it over the Christmas break (using a basic model) and see what happens, and while thinking about it I had an idea.

When I was playing with G era double boxcars I found out that the body file didn't have to be centred on Y axis 0, and what was important was having the ends of the truck meshes centred on Y=0. This doesn't matter much for the "tender" (rear unit of the Garratt) since that can just be done normally: centre the body at Y=0 and have a truck each end to do the pairs of small bogies.

However, it may allow better behaviour for the "locomotive" (front and middle units of the Garratt). If I can get away with declaring the main front unit as the loco body, even though it is offset to about Y= -38, then that might allow me to declare the front and rear bogies of the front unit as trucks and still have them behaving properly relative to the body. This is because trucks pivot off the body, so if the body follows the track then trucks pivoting off it should work. The middle unit of the Garratt would then be declared as a third truck, and should just tag along nicely with suitable positioning of the rear track point.

AD60_Garratt_2.jpg

The advantage here would be that instead of the entire front unit being rigid (and it's pretty long) it would have front and rear trucks that followed the track (ie: they will turn relative to the main unit) so it would look better around corners. So I'll whip up a test model soon, and see if RT3 wants to be nice to Garratts again.

[Gumboots]

Ok, tried it. Got the thing running, as described in the previous post. For the moment I just used the Pennsy H3 skin, because I was already using that for wheels and drivetrain components. For this test I just wanted something that looked like a locomotive, so the skinning is a bit of a mash-up right now, but it gives the general idea.

Quick_test_new_geometry.jpg

With the geometry set up this way there is good news and bad news. The good news is that behaviour over undulating track is now very good. It doesn't look stupid, and behaves much like any other loco/tender combination. The other good news is that without trying it looks more or less decent for skinning, so as long as I don't go OCD looking for perfection I can skin monster Garratts to a reasonable standard. So, monster Garratts are feasible game assets.

The bad news is that, for the front and middle units, the behaviour around corners is not as good as I would like. It's looking like the best compromise will be something that doesn't screw with the game engine's expectations quite so much. So, it'll probably end up with the front tank/bogies/etc coded as Truck1, and with the body file geometry (if it has any geometry) centred on Y=0. This will make it as good as the double cargo cars round corners, so pretty good anyway.

Edit: Just re-jigged it to use that geometry (all front unit bits as Truck1). It's better for behaviour. Zip attached.

The "tender" (rear unit) is fine around corners, except for the usual RT3 game bug of scrunching around right turns and stretching out around left turns. This applies to any loco/tender combination, or to any cargo cars in the consist. It's not ideal, and is why I'd prefer to make smaller Garratts without using the tender slot for the rear unit. However, if monster Garratts are wanted (and I definitely want them) then using the tender slot for the rear unit is going to be the best compromise for all-round decent behaviour.

The other thing I found out is that you can't have smoke coming from trucks. You can have steam and lights on trucks, but apparently not smoke. No idea why they'd screw us on smoke, but they did. Fortunately for this Garratt it doesn't really matter, because the chimney ends up close to the Y=0 point anyway, so the smoke file can be attached to the body file and it still works ok.

Anyway, the current rough beta is attached if anyone wants to mess around with it. Note that this does have monster mash skinning and very provisional stats, but it runs around tracks more or less like it should. If you are going to try it out, I recommend removing any files for the old AD60 basic beta if you have those installed.

[Gumboots]

I've done my usual scatterbrain stunt again. After thinking about a scenario for pioneering rail days in Australia, I decided I would need locomotives for it. That meant I would have to actually make several of them, and it would take forever if I agonised about every detail.

So, just because I felt like it, I started with the NSWGR Class 9, a 2-2-2 of the Crewe type, which is a type RT3 doesn't have any examples of yet, and which makes a good companion for the Class 1 0-4-2 in the 1850's. Class 9 for express, Class 1 for mixed and freight (because back in those days NSWGR didn't have any real freight haulers). The advantage here is that I don't have detailed plans for the Class 9, so I can't do too much agonising. All I have is a rough NSWGR profile diagram and some general knowledge about the type.

After thinking about it on Saturday I started the Blender work on Sunday. It's now Wednesday and I have it running.
Skin still needs a bit more work, but everything functions. If I can rework my brain to do locos like this, I might get some done.

NSWGR_Class_5_beta.jpg

[Gumboots]

Ok, more mutants. Since I'm currently beta testing a revamp of the Blue Mountains scenario I'm naturally thinking about more NSWGR choofers.

The 9 Class (or 5N on the Newcastle network) shown in the previous post was built by E.B. Wilson & Co. The same company also built the 8 Class and 12 Class 2-2-2 well tanks for the Sydney network, and I have about as much information for them as I have for the 9 Class (IOW, some basic dimensions and stats, along with a profile drawing). Since I was getting a feel for the Wilson locos anyway, I whipped up the 8 Class to a basic level. It's a rather weird thing though and I'm not sure it'd be much use for RT3, so I haven't taken it further.

That got me thinking the next Wilson that would be useful was the 6N Class: an 1863 4-4-0T for Newcastle coal haulage. There is one photo of this thing that I know of, and no other details whatsoever. Fortunately the photo is pretty good, and having got a feel for the Wilson style I figured I was capable of making some educated guesses that were near enough for RT3. This turned out well. It's a decent looking loco and should provide a useful little freight hauler for some scenarios. It wouldn't be hard to do an express version later either (Beyer Peacock built express 4-4-0T's for a range of railways in the 1860's). This one isn't running yet, but is at the stage where getting it running will be pretty simple.

6N_Class_shot_1.jpg

6N_Class_shot_2.jpg

The differences between it and the 8 and 12 classes are interesting. The 8 and 12 classes were well tanks, with most of the water carried underneath the crew/footplate area and the filler coming up through the coal bunker. It had to be carried here because the firebox and valve motion were taking up the space between the frames further forward. I was wondering why they would have changed from well tank to pannier tanks for the 6N Class, but think I have figured it out.

In the 1890's the NSWGR got a bunch of Baldwins (Ten Wheelers and Connies) and there ended up being a Royal Commission (ie: high level investigation) into whether they were too much for the NSW track. The Baldwins were found to be fine (problems raised were due to poor track maintenance in some spots, along with a bad batch of axles that were replaced under warranty) but one odd detail mentioned in the evidence was that the early Wilson well tanks had a tendency to break rails.

Looking at the way they were arranged, it's clear that with the well tank full the load on the rear axle would be much greater than it would be with the well tank empty. I think what happened is that, when the tank was full of water, the rear axle overloaded the rails that were available in the early 1860's. This would explain why after experience with two Wilson well tanks, the NSWGR would want a change to pannier tanks for their new freight units. With pannier tanks the weight of the water is spread evenly over the two driving axles, which is the best place to have it for adhesion and would keep the axle loads within the rail's limits.

As near as I can figure it, by taking measurements from the available photo and running comparisons with known factors from other locos of the time, the 6N Class has 16" x 26" cylinders and 54" driving wheels. This would have given it around 1/3 more hauling power than the 1 Class 0-4-2 that the NSWGR started with, and slightly more than the 23 Class 2-4-0 that would be introduced in 1865. The front truck seems to have been 36" wheels with 4 feet between axles, which was common for four wheel front trucks of the period. Bissel trucks weren't in use at this time, so the four wheel front truck was presumably to deal with tight curves around collieries and docks. By 1865 Bissel trucks were in use, so the 23 Class had them.

[Gumboots]

Go the 1 Class to the point where it's all UV mapped and has most of the mesh detail it will need. At the moment it's using the basic 9 Class skin (see a couple of posts back) just so I could see it all in more or less the right colours and get a feel for it.

NSWGR_1_Class.jpg

Will re-pack the UV's tonight, to rationalise it all, and some skinning that's specific to the 1 Class. Poly count is going to come in about the same as the Pennsy H3, give or take a dozen. Have got the stats pretty well figured out too, although they'll probably get tweaked slightly after testing with the actual scenario.

Historical stuff: Turns out I was partly wrong about the well tank locos. They did usually carry some of the water in the second tank in front of the driving wheels, so the loads when tanks were full were pretty balanced. At least this was the case for similar Stephenson units of the period, so I assume the Wilson ones were the same (makes sense). However they still had a name for breaking rails, or at least playing havoc with them sometimes, and this is probably related to axle loading. A tank loco with full tanks is going to have a higher axle load than with empty tanks.

Back in the mid 1850's the NSWGR was using Barlow rails, which were a trendy thing for a short period back then. They were cheaper to lay, but ended up not being as clever an idea as first thought (tended to go out of gauge easily) so most railways replaced them with normal rails and sleepers during the late 1850's.

I've found out that reports from the time say the 1 Class played havoc with the Barlow rails too. This was why the NSWGR rapidly went to getting quite a few lightweight 2-2-2's for the Sydney lines. Being lighter, the 2-2-2's were easier on the Barlow rails and they were adequately powerful for local passenger services. The 1 Class, which was built to haul anything and everything including pax and mail, ended up only being used for freight and shunting duties.

For RT3 scenarios I could emulate this by making the 1 Class and the well tanks have low reliability, but that would annoy me so I'm not going to bother. There are limits to my taste for reality.

[Gumboots]

Got some more done. I'm starting to really like this loco. Still needs a bit more detailing, but I might get it running tonight just to see it trundling around. Livery is the same as the original in the museum in Sydney. I'm assuming their research is pretty good and their paint job is more or less accurate for the 1850's.

NSWGR_1_Class_skinning.jpg

Not finished, but running. Quite an appealing little beast.

Ok_it_works.jpg

[Gumboots]

I'm finding this one far more enjoyable than I expected it to be. I've mostly been detailing the tender, but have also got a bit more done on the locomotive and the end is in sight now. Still needs some smokebox detailing (rivets, door, etc) on the loco, and brakes for loco and tender, plus a couple of other minor bits (pipes, etc) but it's all coming together nicely.

Builders_plate.jpg

Tender_detailing.jpg

Found a good trick for profile icons too. I've been trying to render them out of Blender screenshots that were taken over a green screen. Turns out that green screens may be good for movie background trickery, but they're not so good for profile shots with the combination of Blender and DDS textures. Changed to using a black background screen instead, and suddenly it's much easier to get clean icons cut out. Far fewer artifacts to worry about, and being black they're less noticeable if you miss a few.

[Gumboots]

Got some loco detailing done, and a few minor changes to the tender. Poly count has dropped to where it should be: slightly more than the Penny H3, but not much. Just needs a bit more eye candy and it'll be ready to rumble.

Loco_details_2.jpg

Loco_details_1.jpg

[Gumboots]

Haz moar eye candy. I found myself looking at it in Blender and thinking "This thing is too good for RT3".

Numbah_Wun.jpg

Too good is better than not good enough. Still a couple more details to go: brake handle on the tender and a couple of pipes on the loco. Should be able to knock it off tomorrow. Which is good, because I'm over working on it and want to play with it instead.