Geometry of feed dog cam
 

If you like to study a bit of geometry, then I think you like to watch this video about how the feed dog cam is made in most sewing machines. The cam ensures, that the feed dog stroke do not move for some parts of the sewing cycle.

Video about feed dog cam

That was very interresting, thanks.

I get audio but no video????
- Correction, it loaded fully the second time I tried it! Interesting!

Thanks for your replies. I did wonder for some time why the feed dogs moved like this with a complete stop in the ends. So with google I tried to search for information, and it was quite hard to find any, but I did finally find some info in very scientific terms. Therefore I decided to make this a bit more popular video about it. I guess even children with some interest in geometry might find it funny.