DateTime Conversion works for string value but for calculated value throws "out-of-range" error So I keep getting an error and I have no clue what is prompting it. I have the SQL 

STUFF(STUFF(STUFF(CAST(((ETADate * 10000) + ETATime) * 100 AS NVARCHAR),13,0,':'),11,0,':'),9,0,' ')


Which produces on the problem line the value :

'20161102 00:50:00'


When I call the following SQL, the DateTime conversion works just fine.

CONVERT(DATETIME, '20161102 00:50:00')


But when I try to put both together with the following:

CONVERT(DATETIME, STUFF(STUFF(STUFF(CAST(((ETADate * 10000) + ETATime) * 100 AS NVARCHAR),13,0,':'),11,0,':'),9,0,' '))


Then and only then, I get the error "The conversion of a nvarchar data type to a datetime data type resulted in an out-of-range value."

Does anyone here have any clue as to why the my nvarchar to datetime conversion works when I manually supply a string but fails when I try to convert from math that generates the exact same string? Any insight anyone has would be great because as of now this makes absolutely no sense.
Are you able to use date based functions to build your datetime.

Select
Dateadd(hh,11,
Dateadd(mi,50,
Dateadd(ss,30,
Convert(datetime,eatdate))))


Sorry if I've made any mistakes, I'm typing on my phone.