Re: Process Control (Stencil Printer)| 12 January, 1999
| What would be a good metric for process control of a stencil printer? (fully automatic, vision equipped, stendil printer). | I'm doing some more DEK 265 GSX's with everything imaginable hung on them. Have done Lt's and the MPM2000. This makes machine evaluation and qualification the starting point followed by:
1) Board and assembly design 2) Stencil matching board design and and capable of meeting assembly requirements 3) Board solderability and cleanliness having been dessicated properly or baked 4) Global fiducials and the machine's vision system's abillity to recognize and align to them 5) Solder paste type, storage, handling, shelf life, tack time, application amount/methods 6) Squeegees (material, speed, pressure), if employed - if not automated paste application methods, management, and effects as amount, accuracy, profile to effect acceptalbe solder joint quality 7) As important as the foregoing are excellent operational procedures, company dedicated operator training, and highly effective process management with SPC and real time feedback for immediate corrective action and long term continuous process improvement 8) A clear visualization and realization of what does it take at printing to achieve acceptable solder joints. 9) Also important is the board support tooling system and a well though out program for production with not bottlenecks to slow down that Fuji 40k CPH super machine (s). Underscreen cleaning important as well as post process cleaning and stencil handling. There's a damn lot of stuff for about the most important process in the whole SMT production cycle.