Jeremy, your pen looks beautiful, I love the matte finish.
Tim, when I get close to the shape I want, on spalted woods, I stop or turn the lathe on low and coat with thin CA, let dry, only takes a few minutes. When I get to the shape I want before sanding I wipe the blank clean and coat with thin CA again and let dry. I start sanding and don't do the slurry on spalted woods because of the black. If I'm not mistaken the CA tends to keep the black from entering the pores of the rest of the wood. Hope this helps.