The high tech and fancy tools like EnRoute software and a CNC router are very nice. I simply couldn't manage without them for they allow me to do some pretty cool projects. But I love my other simpler tools too and often we can do marvelous things with a very basic approach.
For the wood grain on the barrel I used the simplest tool imaginable. I squeezed the sculpting epoxy on with my fingers, whetted it down with water and then broke out one of my favorite less technical tools - a stir stick from the paint store. Sometimes I use a razor knife to trim the end a little or shape or sharpen it. This time I used it stock without any adjustments.
The key to using it properly was the angle of attack. For the joints between the staves I sculpted with the stick held up at 45 degrees to the surface. For the woodgrain it was held flatter and dragged along to form ridges. I created the ridges so they threw a shadow and in the process became more prominent - especially in directed or controlled light.
I've been sculpting two boards per session in order to not muck things up. Once the epoxy hardens I'll do the next sections.