Inaccurate exporting of animation from 3DC to Railworks?

I’ve animated the valve gear of a steam loco I’m building in 3DCrafter, and the animation runs smoothly in 3DC. However, when the animation is run in Railworks, there are “hiccups” in the animation of the parts that don’t follow strictly circular paths (like the eccentric rods and links). The end of the rod that is connected to a circular motion (like the end of the eccentric rod that’s connected to the eccentric crank) does go round in a smooth circle, but the other end, that follows a sort of pringle crisp shaped path (swinging back and forth) suffers a “drop” out of the path at one point, before popping back up into the correct path at the next animation step. This happens only in RW, not in the 3DC animation window, so I wonder if it’s a problem with the .ia exporter.
By the way, I didn’t use any wizard to do the animation. I preferred to do it manually because of the complexity of the Walschaerts valve gear.

What I found is that the drop occurs at the same place where I have trouble setting an animation step on the eccentric rod. One end is following a circular path and works fine. The other end goes sideways and slightly up and down. The problem is that when I need to raise that other end a small amount from horizontal, when I let go of the mouse button, the part doesn’t stay where I left it – it drops down to the horizontal. Same happens if I need to lower it a bit (say, around 0.2 degrees). I have to raise (or lower) it just a little bit more until it stays put. Is it coincidence that the big “bump” in the animation in RW occurs at the same place? It looks like in RW it’s doing the same thing … ignoring the position I set and instead springing back to horizontal. I think it must be a problem of rounding or truncation in a arithmetic operation, and perhaps it’s not the fault of the exporter.

Hi,

It\\\’s a bug in the game – it\\\’s been there since the first Railsim.
It only happens on animated groups that are child groups of another animated group.

The only way around it for now is to move child animated groups up a level in the hierarchy and re-animate them there – it\\\’s a bit fiddly but should work.

Thanks Paul, that did work. At least, it got rid of bumps that appeared in the game but not in the 3DC animation viewer. However, I still have the problemof not being able to set correctly the position of the oscillating end of things like main rods, eccentric rods and radius rods. The “snap to” (and I’ve got snap to disabled) seems to occur when the part I’m trying to position is near to horizontal. I can place the end that follows a circular motion very accurately, but the other end just won’t stay in the exact position I place it just before releasing the mouse button. When I release it, it snaps to some nearby position (the error is in the y-axis). This ruins the look of the animation (for example, the piston end of a main rod is supposed to follow a purely horizontal path, but because of this bug, it wobbles, following a pringle-like path).

more or less the same subject. Is there a way to remove all animation information from your models in 3dc.
i.e if you want to start fresh or animate the same model in a different way.

Hi Peter,

In the animation toolbar, at the left side, there is a red cross, pressing that button should delete all animation information from your model.

Regards

Gerrit

hi Gerrit, yes that deletes the animation and takes it back to the first key frame, is that effectively deleted everything?