Whenever I lay a sticky piston, it usually behaves like a regular piston and does not pull the piston attached when deactivated. Approximately 80% of the sticky pistons do not pull properly.
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Comments 4
I'm assuming since your trying to pull a piston with a piston that you are aware that a sticky piston cannot pull an activated piston. If your deactivating both pistons at the same time then this error can occur (and will be a duplicate bug). You need to set a delay on your back piston from retracting the outer piston, until the outer piston retracts first.
Please post a screenshot of your specific design.
Also, your Java is out of date, I would strongly suggest downloading the update from http://www.java.com/en/download/ and turning on auto-updates following the instructions at https://www.java.com/autoupdate/ .