I definitely remember something like this and ever since I found your post last night I can't shake the feeling that if I could just remember more I'd be able to help.
I've done a lot of research but I haven't found anything concrete yet. I wanted to ask a few questions that would help me. Just let me know what you can.
1. You said its been 28 yrs, so you saw it around 1984? If so, this would narrow it down to only the episodes that aired between December 1, 1977(when Qube first went on the air) and 1985.
2. Are you sure it was stop motion? or is it possible it could be animated?
3. Do you have (or anyone here actually) any episodes of Pinwheel that I may look through to help?
It would actually be nostalgic for me, so I wouldn't mind doing that to help, but I cannot find any full episodes online anywhere. I contacted Pinwheel Playhouse but unfortunately they only have footage of the live action scenes. I also contacted those with Qube, but they also only had access to some of the live material, and didn't have any information to help find where most of the animated shorts came from, let alone the names of any.
I hate that I'm showing my age here, being female and all we tend to hate that, but I KNOW Clockman is out there and I want to help.
[Edited on 01.16.2012 2:34 PM PST]