question about clip editing SONAR X3

I'm having a little trouble editing clips. 
 
Here's what I'm trying to do - I've got a clip on my track. I only want to use part of it, and, I want to add an echo trail on the part I want to keep. So, I split the track, and delete some of the clip that was at the end.Then I use the blue handle to split edit the remainder, drag out the handle to the right to get some empty space at the end, for the echo trail.
 
Lo and behold, the part I deleted earlier, reappears! I cant split-edit to get any empty space. Every time, the part of the clip I deleted earlier, comes back.
 
Instead I'm having to create a new track, throw the echo on the FX Bin for that track, and drag the edited clip onto that track. This does work, however, I've got multiple clips on this project that all need echos, and this would require a different track for each clip.
 
Anybody know what I'm doing wrong? I just want to split a clip and delete part of it, and when I delete it, I want it to stay gone.

No I dont think I am applying "trimming" after the split. That may be what is wrong.
 
How do I do this? Is it in a menu?

I found it -thanks for the tip, I never knew this before, I'm sure this is the answer. Thanks!
 
To permanently delete slip-edited data
1.
Select the clips that contain the slip-edited data you want to delete.

2.
Select the Track view Clips > Apply Trimming command.

SONAR permanently deletes the slip-edited data from the clips you selected.