(Safer) Semi Automatic Cobblestone Generator

Today I built a Safer version of the Cobblestone Generator and so you don't loose cobblestone in the lava!
Using pistons! Light is on when machine is off and turned off when machine is on! (Great logic there)
The reason I have bedrock in it is because I don't know why but sometimes it pushes cobblestone after it already pushed one and keeps making it a bigger line!
If you have a solution for this please let me know!
This is one of my first big contraptions so expect more better ones in the future!!
Thanks!
If you want a tutorial on this comment below!
It's a pretty easy design and I tried to show all the redstone involved!
So enjoy!
To save world Press Ctrl+S to Download!
More contraptions to come!!
WordOut