what formula do I get a time of day field to read another time day and add 8 hours?

You be able to make a new formula field  called [TOD + 8 hours]

[my time of day field] + hours(8)

And you can have a form rule which says that when the end time is blank and the start time is not blank change the end time  to be the value in the field [TOD + 8 hours].

You would have to test but you probably need to have that formula field on the form for the form rule to work properly. If you find that you can put it into a section of the form which is hidden by a form rule.

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Mark Shnier (Your Quickbase Coach)
mark.shnier@gmail.com
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