Have a look at this pic.
If you try to close the tipper bed you'll find that it's not always easy. Sometimes when you use the green arrows it will close shut, but sometimes it will not close properly, leaving a small gap. I've found that when trying this, only about 1 of 5 times it will shut absolutely close. Surely an irritating "feature" in LDD, but that's how it is.
Now for the challenge: Besides the "trial-and-error" method there are a few methods that will close the tipper shut 100% of the times. What are those methods? Explain in text. Scoring: one correct method gives you 1 point, two correct methods 2 points and so on.
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