We have a problem with one side of the stapler. The staple on B head side is never flat and sometime breaks. I tried to ajust the position of the head but it didn't change anything. Any tought on this?
So if the problem is minimized by switching the heads, but still present in the same staple position, I'd say you should look at the clincher next.
I had a DBM 120, which I think is similar to your 150. The clincher could be removed by loosening two nuts and lifting it out. Open it up and check for free movement of the swinging staple-curving anvils. BE CAREFUL! Tiny parts lie within...
Sustainable Printing Goes
Far Beyond Using FSC Certified
or Recycled Paper
This informative paper on deinking: demand, principles, problems and solutions also explains why printing technologies are not all equally compatible with paper recycling systems; and why just a small fraction of printed material in the paper can cause difficulties. Link To White Paper