Here are instructions for a cool element with a locking mechanism. It's quite simple and works about 90% of the time. You can use this multiple times like I did on my Ball Machine Eclipse. If you want to see it in action you can always watch the video.
If there are any questions/ problems feel free to ask me in the comments below.
Thanks for watching/ building,
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.
On the first picture you can see how it should look when it's locked into place. So when you push the little handle up it's should release everything and it should look like on the second picture.