DRG class 39 2-8-2 (cancelled)

[Gumboots]

K, gonna start on this beastie, since out of the 1.06 locomotives that need fixing it's one of the more inspiring ones to work on (IMO).

I've had a look through old threads, but can't find anything on the rationale for including it. Currently it has a very grotty skin. This got me wondering why it was included in the game. Grotty skin implies freighter, but the BR39 was actually a top express loco specifically built for nasty grades. It was more or less the German equivalent of the LNER P2 2-8-2, being designed for very similar service requirements. This means in service it would most likely have been kept tidy.

Anyway, if the idea of including it was as a freighter, someone got their German locomotives mixed up. Does anyone know why this one was included?

So, new skin, since it needs one anyway because of alpha problems and all that. My inclination is to paint it up in the original Prussian state railway livery, just because I like it more than the Darth Vader red and black DRG livery.

The original form of these critters was like this:

P10_original.jpg (53.02 KiB) Viewed 7433 times

That's still not totally original because the first ones straight out of the shop had no smoke deflectors, but they were added fairly early on. Of course, if someone wants the Darth Vader livery that can always be added as an extra skin.

[Stoker]

Good luck on the skin, if you can get it to look anywhere near as good as that superb model you posted ti will be a great improvement over the original.

[Gumboots]

Due to the limitations we have to work under for this stuff, getting it looking that good isn't really practical. It can certainly get a fair bit better though.

I'll start with fixing the drivetrain basics and make a bit of a tut out of that, just in case anyone decides to help out with some of this stuff.

Incidentally, I find the high-end modelling scene useful for details stuff. Those guys are fanatical about getting things right, and research their prototypes like crazy. If you can find shots of models from some of the top manufacturers and/or custom builders you're well set for anything you might want to do in RT3. Often finding good quality detail shots of the prototype can be difficult, so having clear colour pix of models is handy.

Finding plans is good too, but the number of prototypes you can find free plans for is rather limited. There's a fair amount available for the British stuff, and a surprising amount for the French stuff, but the others are trickier to track down.

[Gumboots]

w00t! Jackpot! I am founden der Schnellzuglokomotiven plannensiten! <(that' s German, that is)

UInfortunately said plannensiten lists just about all of the main ones except for the BR39. You get that.
If anyone wants details of DRG locomotives of various types, try this page: Typenskizzen und technische Daten von Einheits- und Neubaulokomotiven.

Which reminds me, one of the best tools ever for RT3 modelling work is this one: Google Translate. It may be far from perfect, but it's a lot better than nothing.

Although sometimes Germans do use English. Like I've discovered the German for "Click here" is "Hier klicken". It's always handy when Germans use English.

[Gumboots]

Bonzer. I'm getting more cunning now. Funnily enough, it seems you get better results for German choofers if you use German search terms. Whoever would have thought it?

Searching for DRG class 39 or whatever gets you some stuff, but if you fire up Google translate to tell you that the English "drawing" translates to "Zeichnung" in German, and the search for "Baureihe 39 Zeichnung", you get all sorts of handy stuff like this:

Eisenbahn Journal - Sonderausgabe 1985_04 - Baureihe 39.pdf

and this:

Die Baureihe 39. Die Geschichte der preussischen P10

If you're wondering, apparently "Sonderausgabe" means "special edition" and "Geschichte" is "history". Don't ask me what "Baureihe" means because Google doesn't know either.

[Stoker]

Good sleuthing , Gumboots. All of my Great-Grandparents on my father's side were Deutsch speakers from Belgium and Switzerland. My Grandparents could speak German pretty well too. I gleaned a bit of this and can pick out a word here and there when I see printed German. I know (without googling even) for instance that "Eisenbahn" translates literally to "Iron Road", or "Railroad". I run into problems trying to figure out all of those specialized extra-long words that are so popular in Deutsch though. These days I actually know more Español than Deutsch because of my geographic location and working in the construction trade, where there are quite a few hombres de habla española. In English you might say there is a plethora of Spanish speakers around here....

[Gumboots]

K, having found all of that, we now have enough info (even for me) to start fixing Gunter der Nontankenenginnen. No, I wont be putting a stupid face on the front of him. Don't even think about it.

First problem is the driving and coupled wheels (call them all drivers if you like). They're the wrong size for a start, which is why they don't fit very well. The hex puts the axles 4 RT3 units above the track, which translates to 80" (2,030 mm) drivers. That's a bit on the large side, since they're only supposed to be 1,750 mm (69").

Dropping the axle height by 0.55 RT3 units means the cylinders, etc should come down by that amount too, and will also require some tweaking of the connecting rod and coupling bar attachment points (see notes here).

Looking at the model in the game, you can also see that the drivers only have one layer, which gives a rather crude appearance, and they are set to the outside of the track rather than the inside. Also, the coupling bar is set too close to the centreline, and visually interferes with the drivers. This seems to be because whoever made this one moved the connecting rods and coupling bars closer to the centreline. The Class 01 model this one is based on doesn't have the same problem, so it's easy to fix by just moving those bits back out to where they should be.

The other thing is the overall length of the body. Looking at the existing model in the game, I can tell that if the driver diameter is reduced to the right size and the drivers moved forward to sit where they should relative to the cylinders, there's going to be a rather large gap between the ashpan and the rear drivers. So, check the hex for measurements and it turns out the length between the front of the smokebox and the rear of the cab is 56.9 RT3 units, which is 569 inches or 14.45 metres. For a BR 39 that length should be 12.47 metres, so currently it's 2 metres too long. It needs to be shorter.

Also, on a BR 39 the ashpan actually sits between the rear drivers, while the Class 01 model this is built on has the ashpan graphics set so wide that the sides of the ashpan are outside the drivers. Fortunately that's not a hard one to tweak, so add that to the list. There's other stuff that needs doing, but this is a good list to start with since it'll knock most of the beast into shape.

Will make a start on it tonight.

[Gumboots]

Good sleuthing , Gumboots. All of my Great-Grandparents on my father's side were Deutsch speakers from Belgium and Switzerland. My Grandparents could speak German pretty well too. I gleaned a bit of this and can pick out a word here and there when I see printed German. I know (without googling even) for instance that "Eisenbahn" translates literally to "Iron Road", or "Railroad". I run into problems trying to figure out all of those specialized extra-long words that are so popular in Deutsch though. These days I actually know more Español than Deutsch because of my geographic location and working in the construction trade, where there are quite a few homdres de habla española.

I like doing a bit of sleuthing before starting to change things. Helps to get a good feel for what I should be aiming at.

German and other European languages are related to English of course, so often there are words that will stand out as being obvious. I was grinning when I saw "hier klicken" on one of these sites. Other words you just have to learn, but restricting yourself to English search terrms is going to be a handicap if you want to learn about non-English stuff. I should have thought of that before. Handy lesson.

[Stoker]

LOL- Ya ninja'd me and quoted my typos while I was fixing that post. And missed the belated plethora point as well.

[Gumboots]

I think I've figured out a basic algorithm for translating English into German. All you have to do is merge words so that everything is at least 6 syllables long, add "en" to the end of everything, and randomly swap some esses for z's. To translate German to English, simply split words up so nothing has more than 3 syllables, throw away any "en" bits, and randomly swap z for s.

The result will be a bit rough, but not much worse than Google Translate.

[Stoker]

Jawohl, Herr Kommandant!

[Gumboots]

K, let's get back to Gunter das NonTankenEnginenen. Since I've got plans for him I'm gonna use them. I reckon it's easier to just whip dimensions off a good drawing and chuck them into the hex at scale, rather than trying to wing it. If I use the plan dimensions it should all fit and look right without any head scratching. Turns out I can centre his rigid wheelbase (ie: drivers + coupled) on the zero point for the body file and it'll all work out nicely balanced for overall length each end.

For track attachment ponts and truck pivots I'm going to try some ideas. I have a sandbox set up with a succession of tight hairpin corners between two stations, just for geometry testing. These corners are the tightest that the track will lay around smoothly. I was playing with the Class 01, then had a bit of a play with the Big Boy and the Berkshire, and I think I'm getting a handle on how to set things up for best effect (which may mean more Berkshire revamping at some stage but we wont talk about that).

The default locos usually have truck pivots somewhere within the truck, but after trying a few things I'm convinced this doesn't work as well as some other possibilities. What seems to work best in terms of wheels following track is if the pivot points for the trucks are at the track attachment points for the loco body, and if those points are at the front and rear drivers.

It comes down to a compromise between the rear of the loco swinging out away from the tender if the rear track attachment point is too far forward, and the drivers tending to look derailed if the track attachment points are spread too far out. This gets a bit gnarly with something as long and extreme as the Big Boy, because that's so out there that nothing will be perfect on really tight RT3 corners, but should work well for Gunter since he's pretty short in the ends.

[Gumboots]

Oooooooooooooo_kkkkkkkkkkkkkkkkkkkkkkk. Well, I just found another trap for young players in this evil old game engine.

So I'm setting up Gunter's revamped drivetrain. I get clever and take one of my existing sandboxes, change the loco to Gunter, then save sandbox as "Testing Gunter". I figure this will be nice and convenient because it will already be loaded up with the right loco. Just quite game, copy in new files, restart game and open sandbox again, and it should show the updates, right?

Wrong.

It seems that if you are testing files for a loco and that loco is in the save, it may not update the files correctly when you restart the game.

This is for loose .3dp files put in UserExtraContent to override the default files for that loco. It doesn't seem to be a problem if you're packing up an entirely new PK4 (done heaps of that) and replacing that, just if you are using loose files in a higher level folder to override some files in an existing PK4.

Anyway, Gunter was looking all weird and not behaving at all, and I'm double and triple checking the hex and it's all ok so *** hey? Then I change the loco to a Class 01, then back to Gunter. Suddenly, Gunter is behaving just like he should.

As far as I can tell, this seems to be roughly the RT3 equivalent of having to hard refresh a browser to re-cache code changes on a website. It's well worth remembering. If the loco you're testing is doing stuff you've checked for and just KNOW is stupid, switch to another loco then back again and see if that kicks it into shape.

[Gumboots]

Here's Gunter with all his wheels the right sizes and in the right locations. The coupling bar gfx and a couple of other details still need work (job for later) but it all runs as it should.

Gunter.jpg (52.14 KiB) Viewed 6855 times

I put the new drivetrain together following the principles mentioned here and here. If you follow those, you can build any drivetrain without it going haywire.

As you can see, various things will need to be moved around a bit to fit the new drivetrain. It may seem surprising, but the P10/BR39 actually was physically smaller than the BR01. The difference in size between the two locos accounts for about half the difference you can see in the shot. The other half is due to RT3 locos generally being pretty loose with scale, with the result that their relative sizes often make no sense. I'm going to do all work to the same scale because a/ I reckon it's easier that way and b/ the results willl make more sense when viewing a posse of locos in the game.

[Gumboots]

Gunter is coming along so nicely that I figured it was time he had his own skin. This is just a quick hue/saturation/lightness tweak on the default Class 01 skin, but it gives the idea. He's starting to look like a proper Prussian P10.

Green_Gunter.jpg (108.64 KiB) Viewed 6843 times

I'm finding I'll have some useful bits left over from the original BR01 model too, so should be able to add a bit of nice detailing without upping the poly count.

[Gumboots]

I'm getting cunning ideas for this model. Since the smoke deflectors aren't prototypical anyway for this loco it makes sense (to me) to use their bits for something else. The blockiness of the smokebox geometry always bugs me in RT3 loco models, so I'm going to use the smoke deflectors to fix that by turning them into extra top faces for the smokebox/boiler/firebox unit. This will effectively allow modelling the upper 56% of that unit as 18 sided instead of 9 sided. It'll still be the default 9 sided for the lower 44% but that shouldn't be very noticeable.

It'll work like this:

Boiler_trickery.png (20.98 KiB) Viewed 6608 times

Points 2 and 4 (and the corresponding points at the rear) will be swung downwards and outwards to the mythical Points X and Y (which don't exist yet). Points 1 and 3 will be swung downwards and outwards to where Points 2 and 4 are now. This will leave a wide flat top between the current locations of Points 2 and 4, if that makes sense.

Each smoke deflector is made up of 3 joined rectangles. The two units will be placed to join on the centreline, slightly higher than the top of the smokebox is now. The innermost rectangles will run from the centreline, downwards and outwards out to where Points 1 and 3 are now. The remaining two rectangles each side will make a total of four more planes, two between the current locations of Points 1 and 2 and two between the current locations of Points 3 and 4. The resulting gap on the front face of the smokebox will be patched with the old deflector supports. The end result will make the smokebox end look much smoother.

Since the faces for the old smoke deflectors will be remapped to the existing boiler gfx, this will also free up a bit of space on the skin for something else, if it's needed.

[Tomix]

Excellent work here Gumboots. Your tips and tricks should be stickied, since they are really informative.

[Gumboots]

I'm thinking I should rewrite some of this stuff as documentation for future modelling. At the moment it's a bit all over the place because I'm just posting stuff as I think of it. If this stuff can be documented fairly clearly, it should mean that future modders will find things far less intimidating. This means more cool trains for the rest of us, which is all good.

[Tomix]

I'm documenting things as I find them in the forums, and I'll combine them as I go.

[Gumboots]

Y'know I just had a better idea about that boiler. I'm looking at the various bits and thinking given the amount of work needed, it might be easier to just import a boiler that has more sides.

The Stirling is one of those oddities strewn throughout the game folders, in that it has a 16 sided boiler. This is a very smooth looking compared to the others in the game, but it's hidden between the usual blocky stuff at each end so you hardly ever notice it. Why they did one that smooth only for that loco in that location is something that baffles me, but they did. It's already set up with all the hex for points and normals and faces. I've already isolated its geometry anyway as I was thinking about using it elsewhere sometime.

So, Gunter could do with a smoother boiler, and there's one sitting around looking for a good home. I'll have to reposition the points for length, width and height, but I was up for that anyway. Same for remapping the gfx. Due to the differences between Gunter and the default BR 01, the remapping should be easier this way than if I just mutated all the BR 01 bits. The points in the hex for the new boiler would have to be re-numbered to call the faces correctly, but that's not that big a deal either so it's still looking like a winner.

This also means I can just delete the hex for some unwanted faces (to save processing) while leaving the points themselves alone. Key thing here: leaving existing points alone. If you remove points from the file, that throws out the numbering for all the points after the ones you removed. That means your gfx declarations don't work, unless you go through them all and re-number all the affected points. That's likely to be a very long process and prone to error.

If the points stay in the file and only the faces between them are removed, it doesn't affect anything else except for the total face count at the start of the file (which is easy to change). Adding more points after the existing ones is fine too, since they only need to be numbered to suit and wont throw off the numbering for existing points.

So, short version is that the existing boiler sides will vanish, leaving only the ends for smokebox front and backhead detail. The Stirling's boiler, suitably resized and mapped to Gunter's skin, will be dropped between the existing ends. To deal with the current blocky look of the front end I'll just use a little bit of alpha to round it off. No problem.