For those that have asked- we've used both wooden skewers and heavy floral wire to 'mix' the colors-- colors that were poured into the tube at the same time, pretty much-- alternating to sides. Tried stacking (pouring in one at at time) but that really didn't work too well. Bending the wire can help mix colors to the edge.
But even some of the blanks that look ugly, or all one color, on the outside, are often nicely colored on the inside.
Dark and darks are still problematic. The blue/orange above is not NEAR as good as our first "Auburn" cast. Plus, the advice given by others to paint the barrels or insides of the blanks IS an excellent idea. Mike tested that with a teal/red resin that turned out too bronzy with a regular brass tube. Painted the tube red for the next blank- it made the colors much richer.
Use plenty of white/pearl to keep that from being transculent, and mix well.
Use a black sharpie to mark your 'fill line' on the outside of the tubes, marking them with tube from the pen kit to keep from wasting resin.
We need to take pictures of our Alabama, Auburn and UAH (a university in Huntsville AL) cigar pens to show some pretty colorings. UAH is blue and white--and it has to be one of the prettiest resins he's poured. My son even had UAH engraved in collegiate lettering on it-- so yes, homebrew CAN be engraved!! We've just found it makes dust intead of ribbons.
Any clue how to remedy that?