May one use a salad spinner on Shabbat since he is removing water from the salad albeit it is mechanical not electrical. Would this be prohibited under "borer"?
Since it is accepted practice to eat the vegetables after they've been washed without putting them through a spinner, it is permitted to use the spinner to dry them further. The water on the vegetables and the vegetables themselves are not considered two separate types - water and vegetables - that undergo a process of "borer"; they were together wet vegetables before the spinning (see Shulchan Aruch and R'ma Orach Chayyim 319 10 and the Mishana Berura there 34 and 35) [Shmirat Shabbat K'Hilchata (3 52)prohibits straining cooked vegetables to separate them from the water in which they were cooked, but this is only because he views the water as being significant in themselves (fn. 156. Shmirat Shabbat K'Hilchata bases himself on Rav Shlomo Zalman Auerbach who disagrees with Shvitat Hashabbat who permitted straining the cooked vegetables). Water left on fresh vegetables after rinsing them off is insignificant.