This was an ugly gray office chair we had around that had a broken pneumatic shaft. (I took the first picture after taking one arm off.) My cat really loves this chair and we haven't yet bought her a cat tree, so I thought it would be great if I could transform this into something resembling one. I decided on a two-tiered cat tree with a scratching post in the middle, a few dangly toys and a covered habitat underneath. Click any thumbnail to see a larger pic!

First I took everything apart to see what I had to work with, which was:
chair:
2 cushions
2 arms
1 pneumatic shaft
1 5-arm caster base
1 L-shaped steel bracket
18 1/4" x 1" machine bolts
scratching post:
1 cardboard tube covered in sisal rope
1 bolt + washer
a piece of carpet on plywood
purchased:
new fabric ($4)
4 1/4" x 1.5" machine bolts ($2)
11 #6 x 5/8" metal phillips screws ($1)
1 1.125" x 48" wooden dowel rod ($3.50)
2 tie plates ($0.75)
1. First, the fabric. I know this isn't the flashiest, prettiest fabric, but it was in the $1/yd bin and I wanted something that would jive with our decor. I covered the cushions and stapled with a staple gun. No need to be perfect.

2. I flipped the bottom cushion over and used a 1/4" drill bit to drill a hole in the plywood bottom and up through the padding of the base cushion; I attached the scratching post tube through the center of the cushion with its own bolt and washer. (Major props to my boyfriend, Jason, for being the muscle in this process.)

3. I flipped the chair arms over and reattached them to the bottom of the seat cushion facing the floor. This gave me a rocking base (great stool!) if I wanted to leave it as such, but I needed a bit more stability. I flipped the L bracket over and reattached it using the 1/4" x 1.5" machine bolts. I cut the dowel rod into two legs each 11.5" long and screwed them onto the tie plates, which I then screwed into the plywood bottom to give a firm, stable base to the tree.

4. I used a 3/16" drill bit to drill new holes in the plywood of the top-level cushion and secured the pneumatic shaft to its bottom with its own bolts.

5. Stapled a skirt to the perimeter of the base to make a hideaway.
6. The scratching post is actually a hollow cardboard tube, so I simply placed the pneumatic shaft inside the tube and secured the edges with epoxy. The lift handle was too difficult to remove, so I used it as a hanger for her favorite toys. Ta da!

7. The leftovers. Not much!

Begin: 5/31/08 8:00pm
End: 6/1/08 9:00pm
Total cost: about $10
Total time: about 5 hours not counting trips to Walmart and Home Depot