I'll be honest and admit I read your first post but not the following two. There is no way that you can hit a vein "safely". If you're cutting that bad or planning to then you need help pretty damn quick...

I can definitely underrstand the need to cut deeper. Unfortunately that is a big issue with cuttin. Shallow cuts that satisfy you at the beginning achieve nothing further down the line so you end up cutting deeper each time to get the same effect. When you realise this is where you are at the it's a good time to see your doctor and get some more support before it goes out of hamd....