Just sandwich them between two boards - say 1x3's a foot or two long - allowing them to overhang one edge enough for the sled to clear the bit without being cut into.
Line the pieces up against each other in a row to a "fence" of the same thickness and equal to the length of the 1x3's, then screw the top 1x3 over them through the fence "sandwiching" them in place, and you're good to go. Using two-way tape would also be a way to go, but I'm unsure that tape alone would be sufficient for peices of this (small) size. With pieces this small, it would be a good idea to use the tape in the sandwich, otherwise, they might have a tendency to want to "rotate" slightly as they pass through the bit.
This securing method is quite simple, it's fast, nothing fancy needed and works for many different applications.
good luck with your project,