This is the drum piece for horizontal Faux Wood Blinds. These pieces break and crumble over time. Rebuilding the blind isn't difficult.
I want to give credit to naeblis11 who posted a version which was my starting point as his version didn't fit. I was only able to use his design as a single object so I modified it and created a new square inner shaft of 4.25mm. Also I modified the outer shaft so it would fit in the mounting part.
This print could be better but editing wasn't easy so I made do with what I could and it worked which is more important.
I printed this with the shaft flat to the bottom. Cleanup wasn't really necessary except for the hollow part below where the thread goes. Rough print is fine. I used 50% infill using PLA. You can play with that if you wish.
Be sure to remember to punch out any support left behind in the shaft opening. Depending on your settings you may have a lot or a little. Mine was easy to remove when inserting the rod.
I am including my 123D Design file but not all objects in it are editable.
I added a picture of the actual drum this one would be replacing.