Check Your Short Shot when Troubleshooting…

Recently we were assisting a customer in troubleshooting a problem with inconsistent recovery via email. This was a great reminder that it is always important to check and ensure there is a short shot at the start of troubleshooting most problems.

Customer Issue (shortened): 
During a rear zone study, the customer was encountering complications with the process. After further evaluation, it was found that the screw recovery was fluctuating nearly 40% from shot to shot.
Analysis:
In our experience, an inconsistent recovery is most often caused by an inconsistent cushion (at end of packing). The customer reported a cushion which was consistently at .038in, so at first glance it appeared this was not the problem. Upon further correspondance, it was found that the transfer position was set to 0.040in and a short shot was not being molded. In this case, the machine determined the ‘cushion’ as the forward-most position before screw bounce back occurred.
Correction:
The customer adjusted the transfer up to 0.070in. This obtained a short shot during first stage and provided a consistent recovery time, which was the original intent.
-Andy

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