My wife and my buddy's wife stumbled across 36 NOS spools of silk in Winthrop last summer. We split the thread three ways and one of the spools that I ended up with is purple. I tried tying with the silk this week and love it on some Purple Haze. However, when I applied Hard As Nails, the silk turned dark. A couple of people have suggested that I try rod builders color lock before applying the Hard As Nails. What are your thoughts?