There are how many penturners here? You'll get at least that many opinions as to the best way to color pen tubes. I've found that there is no standard answer. It all depends on what the material is .....how translucent it is and the desired effect you want. IMHO if there was a "standard" color to paint tubes it would be white. Altho with white you run the risk of lightening , or washing out the color of your smaller pens such as slimlines when you turn them down close to the tubes. Black is another choice for darker plastics. Again you run the risk of "darkening " your pens as you near the tubes.
I've reached a happy medium by painting the tubes a color close to the predominate color of the blank. This can also be tricky with multi colored blanks. I use a variety of paints from spray enamels to the small bottles of acrylic craft paints. I've recently stumbled onto something I'm sure more experienced plastic turners already know, but I've learned to paint the insides of the blanks rather than the tubes. My reasoning behind this is: with a very translucent blank you will see the glue in the form of bubbles or wavey lines because the glue is "between" the blank and the painted tube. But if you paint the inside of the blank then the glue is "between" the paint and the tube as is not visible. This is just my two cents worth but maybe it'll help.
I've also begun experimenting by painting blanks such as a very transparent pearl white(I believe it came from CSUSA)with a bright color, say purple and turning the pen. You get some very interesting results. Because of the varying degrees of transparency you got widely differing shades of purple. I'll try to find a pic of a perfume pen I did this way and post it later.
I realize this has been long but I do a lot of plastics and acrylics and to me it's a lot of fun!
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