Making a sound effect: A lift door opening

 

I began with 3 glasses.
 

After hitting each of them with my nail, I decided the two wine glasses were the best for the noise I was trying to create. I then filled them with water to see if that would make a difference.

After hitting them both again, I decided the smaller glass made a better sound as it made more of a rounded 'ding' type sound. I filled it with more water to see the effect this would have on the sound. It made it more compressed and faster, so a lot more like the 'ding' of lift doors. 

I tried to find something to hit it with that would make it even more like a 'ding' lift door sound. I tried it with a butter knife, but this was too thin so I tried it with the handle of the knife and this was the perfect sound.

I then put the sound I created over a clip from the TV show Friends of a lift door opening. Here is the final clip.