I see these very expensive scratching posts at Petsmart.

I was thinking of making a scratchin post.

Does carpet really provide a scratching post for the cats?  These things
they sell look like fun toys for the cat but do they really provide a
scrathin post.  I thought they do that to sharpen and clean their claws.
Would a soft wooden post be a better choice?  I dont see any made of just
wood.  Some had rope wrapped around which seemed a better idea the carpet.

Your thoughts appreciated.

TY