Troubleshooting Basics, part 3

In the previous 2 parts we discussed the defining and planning of the trouble shooting process, the next step is the how to of the Plan, or just taking care of it.
Though the effect is to solve the problem, the doing so can be the key. How do we change things, little steps or big steps? What do we change first, last?

The following are some steps or possible rules of thumbs to consider.

1) From a safety point, know your process, material, tool and machine.  Never attempt anything that may harm you or damage the tool.
2) Document your starting point.
3) Change one thing at a time and note the results
4) Give the change time to react. ( know your machine, is it 3 cycles or 10 to take effect)
5) Document the change and results
6) Temperatures are the last things to implement.
7) If material temperatures are a possible problem increase back pressure first to get the raise in material temperature. Watch position transfer and flow as volume has now changed due to density of shot change.
8) If changing cooling timer/ mold close timer, proceed in big steps to see effect. Moving of the cooling timer 1 or 2 seconds may not show what a 5 to 20 second change would. Note these changes are to give quick results to a direction to move. Once a direction was determine than the amount of time can be optimized to solved the problem.
9) If adding anything to a neat material run parts without additives to eliminate that as a cause, if in fact that makes sense for the problem
10) If in changing things, they do not work, change them back.
11) If you think tool temperature is a factor, which way are you looking at? Tool too cold run as fast a cycle as possible (though parts may be bad for other reasons) and note change.  If tool temperature is thought to be too hot let mold, stay open for a period of time and than shoot and note results.

The point of documentation is critical to a long term solution.  This is usually not done to be honest. Nevertheless, this documentation is key to being successful. You have now created the database for the cause and effect. Further, you have now started your own trouble-shooting guide for your shop, tools, and operation. It now allows you over time to create written instructions for the late shifts to solve those problems that match your previous definitions of problems.

Thanks for the time.
 

Steven L Silvey
Senior Technical Service
General Polymers Division of Ashland Distribution