I was telling Bernard that lately I was thinking about Family of Parts fixturing. It is a really cool idea.
A company has five different products. The shop makes a fixture that secures all of the parts for one unit. Every time the operator pushes the button, they make the parts needed for one unit. Couple that idea with a lock and load sub plate and life is sweet!
You could really calculate time for throughput. The bottle neck would not be the machine shop. There would be no inventory except for metal on the shelf.
If you could fixture a part, and touch it once, a family of parts would be easy to develop. We know that not all parts have one operation. What do you do with that?
I believe that this is the time for the Manufacturer and the Engineer to join forces and merge their experience. There are features that need to be on a part in a particular position and have a particular form, and then there are features that can have alterative positions and forms. For example I have seen clearance cut outs drawn with sharp corners which forced a second operation. I asked, and it was OK to have radii in the corners, and “Yea!” the part became a one op part.
The subject of design for manufacturing should be a healthy part of the new product design cycle. I feel that this has not been the case. Lean manufacturing pretty much demands this.