Hi ESmith,

You can solve this by binding each of the numeric controls to their own property and have those properties update a TimeLimit string/property.  The code below should do what you seek, it will output the calculated time in label1

        protected override void OnLoad(EventArgs e)
        {
            numericUpDown1.DataBindings.Add("Value", this, "Hours", false, DataSourceUpdateMode.OnPropertyChanged);
            numericUpDown2.DataBindings.Add("Value", this, "Minutes", false, DataSourceUpdateMode.OnPropertyChanged);
            label1.DataBindings.Add("Text", this, "Time");
        }

        private int hours;
        private string time;
        private int minutes;

        public int Hours
        {
            get { return hours; }
            set
            {
                hours = value;
                Time = (hours * 60 + Minutes).ToString();
            }
        }

        public int Minutes
        {
            get { return minutes; }
            set
            {
                minutes = value;
                Time = (Hours * 60 + minutes).ToString();
            }
        }

        public string Time
        {
            get { return time; }
            set { time = value; }
        }