Partical animation question

Hello, I have been experimenting with partials and animation with them, however I am unable to find how to animate force. Fro example, I have an engine with a flame in the rear. I want to do an animation of the engine starting up, so the flame would go from 0 force to maybe 3 force over a period of maybe 10 frames. how would i do that? Any help is appreciated, thanks.

set the force to zero, mouse cursor over the buttons window, press I and select force strength. Advance ten frames, set the force to 3, mouse cursor over buttons window, press I and select force strength.

I tried that, The IPO remains a horizontal line, and once it is set to 3, it remains that setting for all of the frames. so basically Force strength is not not effecting/capturing the force of the particles.

Maybe you need to try a higher number than 3. 3 isn’t very high. And once you have it at 3, if you move along some more frames, and set it back down to one, keyframe it again (press I), it will go back down to 1 in the IPO window.

Actually, the setting is between -1 and +1. so that wouldn’t be it. I tried starting it at 1, and it created a key frame at 0 again, and continued to maintain what ever new value i give it. So it still isnt working.

I don’t think I understood your question. What type of force are you using to affect your particles?

I was using the selection under “Particle motion” there is a section that says “force” and was altering the Z value. I also manually changed the IPO curve and no effect on the force was produced. Though i am still somewhat confused as to how a single keyframe value can effect the 3 forces. that would be like having 1 curve for X, Y and Z position combined.

I still need help with this issue. Animating Particle force. Which attribute does the Force key frame effect?