Cell fraction + rigid body settings correct but not working

steel-ball-test.blend (3.3 MB)

I have been working on a wreaking ball which I want to use to shatter a cube. The cube has been cell fractured with the addon. Then rigid body assigned. And then start deactivated enabled after which i have done "copy from active to assign this item to all parts. But it still keeps exploding.

I must been overseeing something. Help is much appreciated.

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The explosion is caused by the floor. Set the collision margin to something like 0.02m.

Start deactivated is currently not working for objects that are initialized with intersecting bounding boxes. You will have to animate the “Dynamic” option:

  1. Uncheck it
  2. Insert a keyframe on frame 1
  3. Link the animation data of all the cells (CtrlL with all cells selected)
  4. Frame step until the ball is about to collide
  5. Check the box
  6. Insert another keyframe

This way, all the cells will become dynamic just before the collision.


  • The origin of an object is considered to be the center of mass (check the wrecking ball)
  • Blender can calculate the mass of each cell with this tool:

    (again make sure all cells are selected)

God bless, and have a great day dude!

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Thank you for your quick reply. I tried your answer but is it still to much of an explosion instead of ball crashing through.

I have noticed something, It seems the wreaking ball is the problem. When I remove the ball and leave the chain, the cube part stay still untill the chain hits.

I have tried deleting and making another ball ( by this hopefully removing any faulty system memory of that ball). But then again start falling apart from de beginning.

But the ball issue is maybe getting closer to a solution.

Select the ball, you open N panel and you see in Transform, “Scale” item.

Always for simulations it is recommended that you have Scale applied (Scale=1) to each participating object. You select the ball and the entire chain, Ctrl + A > Scale.
If objects still react before contact, you can play by reducing Sensitivity > Margin values for participating rigid objects.

Not related to the explosion, but to a good simulation of the ball. I see that the origin of the ball is not correct either. In this case you select the Ball, W key and you select Set origin > Origin to Center of Mass (Volume)

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Thank you !

That was the solution! Applying scale (and other transformations) can be easily forgotten and make you searching for a solution a long time. Great that it now works.