There are many options to holding down material including: screwing the work piece directly into the surface, threaded inserts in a grid, T-tracks, and vacuum table. T-tracks seems to be the most versatile to me and so that is what I installed on my machine (threaded inserts were also tempting). I decided to space them out on 4" centers and I had to work around some removable sections on my machine bed (for the rotary axis and the end joinery areas). If you decide to use T-tracks be sure to remember to leave some open space on the ends to insert the bolts into the tracks. I used 1/4" Mini T-Track from Eagle America.