Richard L. Schmoyer designed the Sunquest sundial to be easily adjusted between standard time and daylight savings time. Simply loosen the wing-nuts that hold the horizontal and vertical crescents together and slide the aluminum plate to the opposite end of the bracket.
The daylight savings time plate allows for a 1-hour time change without making the delicate longitude adjustments needed for accuracy each time daylight savings time ends or begins.
If your sundial does not have a Daylight Savings Time plate, simply move the time scale crescent 1 hour in the appropriate direction, taking care that the longitude setting is correct. In the example of the Sunquest sundial at the Mount Cuba astronomical observatory, Daylight Savings Time (DST) and Eastern Standard Time (EST) were permanently stamped into the time scale crescent.