  The RadiaBeam/SLAC dechirper at the Linac Coherent Light Source (LCLS) is
being used as a fast kicker, by inducing transverse wakefields, to e.g.
facilitate Fresh-slice, two-color laser operation. The dechirper jaws are
independently adjustable at both ends, and it is difficult to avoid leaving
residual (longitudinal) tilt in them during set-up. In this report we develop a
model independent method of removing unknown tilt in a jaw. In addition, for a
short uniform bunch passing by a single dechirper plate, we derive an explicit
analytical formula for the transverse wake kick as function of average plate
offset and tilt angle. We perform wake kick measurements for the different
dechirper jaws of the RadiaBeam/SLAC dechirper, and find that the agreement
between measurement and theory is excellent.
