So drill the benchdog holes through the MDF layer. Begin by laying out their positions. You'll want these to be precise, so that the distances between the holes are consistent. The vises you are using will constrain your benchdog spacing. My front vise worked most naturally with two rows of holes four inches apart, my end vise with two pairs of rows, with four inches between the rows and eight inches between the pairs. Because of this, I decided on a 4" by 4" pattern.
The 84-906 fits this bill perfectly as the table offers all of the qualities and features that you would expect but does not truly blow you away with any of them. For instance, this bench is made out of rubberwood. This wood is decent in that it provides the strength you want, but it is also extremely porous and rough-grained. The porous nature would generally make it susceptible to rotting and staining, though the bench has been lacquered. The rough grain will potentially cause tools to dull over time if you do not regularly relacquer it.
The shelf in the first picture is made of red oak plywood. You can choose the wood type, color and design as you like for your project. In case if you need more help understanding this project, you can refer the source link below. It discusses various items used, steps and tips and personal experience of the author who personally built a Zigzag shelf.