I used ZAP-A-GAP Medium on that build. Thin would be better though.
Sandpaper 220 through 1500.
Wash, then clean with rubbing alcohol.
CA the edges
Sandpaper 800 - 1500
clean with rubbing alcohol
CA the edges again
Repeat the last 3 steps as often as needed. It just keeps getting better. Eventually, your sandpaper will not get any black any more as it's just sanding the CA.