So I got the tip glued on my blade, and was about to put in the blade film when I realized there was dust through the tube. Should have cleaned it first. I tried a dowel with tissue on the end held on by electrical tape to clean it. This just made more dust because I'm an idiot, and got black smudges from the electrical tape inside the blade... I then cleaned it out with soapy water mixed with rubbing alcohol and now there's no dust, but there are still black smudges.

Any ideas? I'm kicking myself right now.