If memory serves, Project only allows block edits (in the calendars) based on weekdays or months. Meaning, you can set all Mondays as 8-5 work days, etc. I think your solution is to create a new calendar with a name such as tenfour. Then set every day to be a working day with the appropriate 10 hour shift. Next, manually count ten days “on” and then for the next four days, set them as non-working days. Count the next 10 days and then set the following 4 days as non-working. Repeating this for as long as needed in the calendar.
Setting every day as a working day with the correct shift is simple. By doing this first, you only need to identify and edit the non-working days and mark them as such individually, which is also simple.
If anyone else knows of a way to simplify this, let us know!
Daryl is correct on how the calendar works. One more thought on the days off. Since 10 + 4 is a two week period, you could setup a recurring non-working entry of four days that go every other week. Create the first time off event, then select the Details button and go every two weeks, four active days, to the duration of the project. Hope that helps.