The scheme of shift 2 ribs

Sometimes in big cubes can have the situation where two edges not fell into place, in this case, you can exchange them for the next uncomplicated movement:

Rotate one part of middle layer on 180⁰	Rotate top side on 180⁰. Put the place for first Yellow pair.	Put firs pair on its place. Rotate on 180⁰	Rotate top side on 180⁰. Put the place for second Yellow pair.	Put second pair on its place. Rotate on 180⁰

The principle of the permutation centers in big cubes

All central elements in big cubes obey the principle of permutation centers on the cube 3x3x3, consider an example:

Blue to Red place	Yellow to Blue place	Return first line to place	Return second line to place	We moved 6 central elements or 3 axis

That is, were the same as in the 3x3x3 cube, only shifted coordinate axis.

Now we can do the next focus. Before returning axises to its place perform substitution:

Rotate Yellow side on 90⁰ and replace Red center on axis to Yellow center	Return first axis to place	Return second axis to place	Blue center to place	Return two layers to place

As a result of this substitution, we have found that 2 central elements exchanged their places, and on the other side of all the centers back to the places:

Applying only this scheme with a different offset coordinate axis, we can gradually put all the central elements. We can also move the central elements, moving several axises:

In the result:

Now making a substitution in the same way, we can to swap 2 central elements.

Another move for a quick exchange pairs parallel of the central elements:

Rotate on 180⁰	Rotate on 180⁰	Return first layer	Return second layer	2 pairs of parallel central elements exchanged

Note we can move several central elements if rotate several layers.