Awesome, thanks guys!

The primer I used is "Vallejo Surface Primer" â€"and I did wash the sprues before assemblyâ€" but obviously I need to give the built parts a wipe before painting. My hands were all over it and maybe there was oil transfer. It had been a good two hours before I started adding in putty but it looks like I was too hasty.

Time to strip it and give it another shot.