Hi Gina - I visit the forum every once in a while... Bill Young set-up my initial hold-down system along with Angus Hines so they are to thank for that! It worked great for larger models but now that I'm getting into more detailed things requiring multiple passes and finer pieces... I've resorted to increasing the screw count. At first, I used 2-3 and when I get cutting new stuff tomorrow... most of the new models will require around 10-15 screws. This is for a Desktop ShopBot using a standard double-flute bit!

The biggest issue I've found is MDF (base material - models made out of cheap 6mm plywood cut from 4ft x 4ft sheets) isn't very good when you screw things in and out... it gets looser and looser even if you move the screw holes around. Cheap plywood also tends to warp quick... hovering around the freezing point in the garage doesn't help much either when filming the cutting/assembling process either!

What I will probably end-up doing is building some sort of frame clamp that goes all the way around the 400mm x 500mm sheet of plywood and a jig around it, sort of like a reversed picture frame once I get a few more ideas fleshed-out. Using higher quality wood would help, but my goal is "proof of concept" and not "retail product" so I prefer to invest money in screws than firewood.

I'm always cutting through the same material thickness using the same board size with the same bit type. This makes my job very easier than most other set-ups.

Jon