Setting up a Horizontal dial

Make sure the top of your plinth is horizontal and wait for a sunny day. For accuracy, set up should be done close to mid day. This is somewhere around 12 o clock in winter (GMT) and 1 o clock in summer (BST), depending on the equation of time reading on the day. This reading can be found on the circular Eot table located on the dial face and its sole purpose is to display how many minutes fast or slow the dial is on any particular day of the year. The reader can then make the calculation to achieve the time by the clock or watch, or more accurately, according to the fashion of the times, a fobwatch.

Example 1.  On JUly 10th the Eot table says the watch is 5 minutes fast, therefore set the dial 5 minutes slower, ie. set the shadow to 12 o clock at 1.05 on this day. (the clocks are 1 hour fast in summer - a sundial is 1 hour slow.

Example 2.  On Dec. 25th the Eot table says the watch is 0 minutes, therefore set the shadow to 12 o clock on this day.

It is recommended that you drill a hole 5mm diameter and 50mm deep to accept the bolt protruding from the centre of the underside of the dial. This can be filled with resin for a secure fixing. A twin pack glue can be used on the underside of the dial for extra security. Both have a time limit before they harden so a piece of masking tape placed near the 12 o clock line is a useful reminder of which way to point it.

Brad Dillon Sundials, Unit 1D, Rural workshops, St Dennis. PL26 8DW

email: tel: 07432 284401