Anyone who's attempted to drill a hole into a dowel or irregular object, such as a turned leg, would understand the frustrations associated with the task. Steadying these kinds of items on a flat drill press table and ensuring accuracy becomes extremely challenging. It gets even more complicated if the hole to be drilled is angled. Typically, I resort to creating a makeshift contraption to hold the desired piece in place. However, ever since I built the adjustable V-block system, this issue has been resolved.  

Video on youtube - https://youtu.be/8_CjtrhTB1Y