My husband and I like to sit in our beds playing Sudoku. We both have the same version and everyone tries to have finished first.

Leaning against the wall is uncomfortable and so I made a headboard out of a guest matress.
First I knitted the cover for the matress in two parts on my knitting machine. Sewing the two parts together was not quite joyfull. To make the cover more dense it had been washed in the washing machine for an hour by 60 degrees Celsius. I used 6 threads of industrie yarns spooled together and knitted 2 x 1200 rows.
The cover is constructed like a fitted sheet with the purled side out.

The double spiral is made of umpty needlepoint thread strands which I got from an old woman who worked at Coats. I sorted the skeins out in two color shades as you can see in the pictures.
The yarn is 30 years old at minimum and I always used 3 or 4 threads together.
The darker rib is from the same yarn as the background.

The double spiral ist knit in one piece. Please don’t ask for a pattern or instructions. I tell you one thing: I made a bunch of swatches until it suits my vision.
I worked in elongating rows to get the form.
But I made the mistake not to follow the archimedical structure. And I ignored the principles of the golden section. So the spiral gots some ruches.

At last I simply sew the spiral onto the background.