MC-27362Fast-moving pistons can swap sand with solid block
Pressing the button on the device in the attached screen shot causes the piston to pump for one and a half seconds. Afterwards, the diamond block is on top of the sand block.
The glitch only occurs if the system is run for an odd number of redstone ticks, so it doesn’t happen if a stone button is used.
The comparator contraption is a 2-clock. If it’s replaced with a 3-clock, the glitch does not occur. Since the goal here was to build a high-precision binary timer, that’s not a very attractive workaround. (No, really. It only looks like a sand duplicator component. 
)
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Fast-moving pistons can swap sand with solid block
Pressing the button on the device in the attached screen shot causes the piston to pump for one and a half seconds. Afterwards, the diamond block is on top of the sand block.
The glitch only occurs if the system is run for an odd number of redstone ticks, so it doesn’t happen if a stone button is used.
The comparator contraption is a 2-clock. If it’s replaced with a 3-clock, the glitch does not occur. Since the goal here was to build a high-precision binary timer, that’s not a very attractive workaround. (No, really. It only looks like a sand duplicator component.
Attachments1
duplicates
[Mod] Ezekiel (ezfe): My version of this bug (MC-27362) is completely reproducible in 14w08a.
Sort of. In my test case (MC-27362) the sand is itemized, which doesn’t make any sense, but is probably better than what happened before. However, I don’t think MC-27362 is a legit duplicate of this, since it involves a sticky piston and sand swapping with a second block above the piston which isn’t present in this report.