Union Pacific FEF-3 4-8-4 Northern type steam locomotive, by Smokebox

[mrennie]

No idea which bit you're looking at, but it sounds as though it might be operating a lever similar to the way a clutch works?

Or perhaps not.

That's more or less what it does. yes. It's hard to explain how all the parts move together, because on each side of the truck (bogey) there are 18 separately moving parts (if you include the actual brake heads and shoes), and they all move as a result of that piston pushing the rear fulcrum backwards. In the real truck, there are various bits for adjusting the length of travel of the connecting rods but I'll probably omit those from the model.

[mrennie]

Piston extended =brakes on.

Good, that means I don't have to redo the animation :)

[FourEightFour]

Yes, the piston should come out about four to five inches at full extension (in a perfect world) if the the cylinder has an eight inch stroke. According to the plans, what size of brake cylinder is it?

I will explain why piston in = brakes off after work.

[mrennie]

Yes, the piston should come out about four to five inches at full extension (in a perfect world) if the the cylinder has an eight inch stroke. According to the plans, what size of brake cylinder is it?

I will explain why piston in = brakes off after work.

It says they are two 12" x 10" UAHS Cylinders with Lever Brackets and Std. Push Rods, giving 65,450 lbs brake pressure at 55% with 50 lbs cylinder pressure.

It looks like the piston stroke is 8 inches.

I just realised that the cylinder is probably fed from a reservoir just like the auxiliary reservoirs on the cars, so it makes sense for the brakes to be applied when the piston is extended - it's when the brake line pressure is lower than the reservoir pressure, so the air is allowed to go from the reservoir into the brake cylinder, pushing the piston outwards and applying the brakes.

[CSX2057]

sweeeet

[buzz456]

Nice to see you going in to so much detail on this...sure wish RSC would pay attention to this and take notes

Oh stop.

[buzz456]

I understand. At the risk of a minor highjack I just think we have come so far from when I started, like you couldn't play the thing for a half hour and it was always crashing and the graphics are sooooo much better and I could go on but I will just say Mike and Mike be all you can be. I'm loving it.

[mrennie]

I understand. At the risk of a minor highjack I just think we have come so far from when I started, like you couldn't play the thing for a half hour and it was always crashing and the graphics are sooooo much better and I could go on but I will just say Mike and Mike be all you can be. I'm loving it.

You're right, TS2013 does so much more than the original RW (or RS before it). I love the graphics effects we have now, especially the detailed shadows (on the highest setting, they really do bring the thing to life). The best improvement of all, which was quite recent, is the increase in the amount of detail the game can handle while still getting decent frame rates. I don't think the Connie, or any of the other highly-detailed assets that have come out in the last year, would have worked very well before RSC did whatever it was they did to get that huge performance enhancement.

Now, back to doing that trailing truck - it's nearly ready for some more screenshots.

[UP3985]

Waiting in greatanticipation!

[mrennie]

Still not finished, but it's getting closer, and it's ready for the animation now. I have to add the pipes and cables (and their support brackets and clips), the safety hangars below the horizontal levers, the rocker at the rear of the truck, the leaf springs above the axles, and tidy up a few bits of texture. When it's done, I'll mirror it all to the left side (and then modify it a bit because I think the left side is slightly different).

2013-05-25_00001s.jpg

2013-05-25_00002s.jpg

2013-05-25_00003s.jpg

[jpetersjr]

Looking great.

[mrennie]

Looking great.

Thanks John

[mrennie]

On my Smokebox faceook page, there's a short video showing the brakes in action:

https://www.facebook.com/photo.php?v=165205066989673&set=vb.132794016882582&type=2&theater

[hertsbob]

Very nice! There's a surprisingly large amount of travel, isn't there. Wasn't expecting to see it looking like that!

[mrennie]

Very nice! There's a surprisingly large amount of travel, isn't there. Wasn't expecting to see it looking like that!

I was surprised too, but according to FourEightFour (an authority on the subject), the travel (in an ideal world) is around 4 to 5 inches, which is what I've modelled. What I'm not sure about (because I've never seen the thing in real life) is how quickly the piston should move. I can tune it easily in the engine script.