A simple problem: I want to add a number to a time and get the end time  to express AM or PM. For example:
Start time = 10:00AM
Duration = 3 hours
End time = should be 1:00PM
I can't figure out how to make this work.

Hi John

Filemaker stores times as seconds from the programmers point of view, so you can just add a number of seconds and FM will do the arithmetic correctly.

3 hours = 10,800 seconds

So 10:00AM + 10800 = 1:00PM

newTimeField = oldTimeField + 10800

 

I finally figured it out. the end time field must be formatted as Short System Time in Inspector. I never knew what that was for before.