minecraft-java-editionminecraft-redstone
I have been following a tutorial on youtube regarding building a minecart station. Now I have had no issues whatsoever until I hit the cart loading section
unlike in the video (19:19 onwards), everytime my Pistons extend or retract, the rail keeps popping and turning into a drop.
Any ideas on how to fix this would be awesome, world save can be provided if it will help with the fix.
I am not sure if I understood correctly, but you can use a sticky piston under the pressure plate to cut off a wire that powers the other three pistons:
And with the pressure plate 'on':
You can power the side pistons with repeaters, if you want the ground to be flat.
Sticky pistons can't move certain blocks, such as extended pistons. I'm guessing your second level of pistons aren't retracting early enough and are therefore not completing their retraction before the sticky pistons try to pull them.
The likely solution is that you need to add a delay to your circuitry which allows the upper pistons to retract first, then the lower pistons a couple ticks afterward. The problem with this is that you need them to extend in the opposite way, with the lower pistons extending first and the upper pistons extending afterward. You may have to use an ABBA switch to create this activation/deactivation pattern for you (extend bottom, extend top, retract top, retract bottom).
Best Answer
Unfortunately, it does seem that some update between 1.4.7 and now has broken this particular aspect of the design. But it's a rather simple fix if you want to continue with this particular Pez Dispenser design (referred in the video as a "cart hopper"). You just need to send the cart forward above the hole where your cart hopper is. The simplest way to do this is like this, with a powered rail pointed towards your cart hopper. You can extend this rail however you like (you can even connect it to the arrivals line, and have it sent back to the cart hopper when you get out of the cart using a pressure plate).
However, some of the recent updates have given redstoners some interesting options with Minecart dispensers; the old Pez Dispenser design is no longer necessary. One of my personal favorite designs these days that combines cart launcher and cart retriever is this one:
When you push the button, the dispenser dispenses a cart, and launches it (be quick to catch it, or you can use a powered rail and a tripwire down the line to have it wait for you). When you come back, break the cart, and the hopper will pick it up and put it back in the dispenser. You can hook this bad boy up to whatever track switching mechanism you plan to use, and you're set.