I made some mandrils out of stainless rod to dip to make the tubes. A 16 penny nail with the shank polished up a little and the point blunted will work too.

I dip the tail color, then trim off the head portion if I want it a different color. Then the rod gets dipped in the head color. I allow the head dip to "just" contact the tail color and then hold the rod at that point in the hot plastic for about ten seconds and things weld up really nice.

I trim the overall length of the tube, remove it from the rod and use a fly tyer's scissors with a very pointed blade to snip the tentacles.

Try a few. If you mess up just toss the bad cast in your bowl of plastic and re-heat it. These are fun and lengths, colors are as many as your imagination.

The molds are cheap anyway....$2.00/pound for 16's? Probably less. Can't beat the price there. By the way, I have a bowl of water right there while I dip these and dunk them right after the tail color. I dunk them again after the head color. Maybe sounds slow doing just 1 at a time but it moves right along this way.