Windows Batch Script Time Stamp - beware the morning space

I had been creating a time stamp just to give my output unique file names so as not to overwrite previous test output.

I'd been doing this:

REM TT= time tag for this run

set T=%time%

set TT=%T:~0,2%%T:~3,2%%T:~6,2%

It works fine after 10 am:

C:\Users\mharrison>set TT=%T:~0,2%%T:~3,2%%T:~6,2%

C:\Users\mharrison>echo %TT%

100359

C:\Users\mharrison>echo filename%TT%

filename100359

I've been using this time stamp method for weeks, but apparently never before 10 am. It broke my code this morning. Before 10am, the plain old time inserts a space:

C:\Users\mharrison>echo %time%

 9:56:08.38

So when I try to append it to make a unique file name, I insert a space in the file name, which confuses the code:

C:\Users\mharrison>set TT=%T:~0,2%%T:~3,2%%T:~6,2%

C:\Users\mharrison>echo %TT%

 95740

C:\Users\mharrison>echo filename%TT%

filename 95740

So I changed the method to only use the 2nd digit of the hour:

REM TT= time tag for this run

set T=%time%

set TT=%T:~1,1%%T:~3,2%%T:~6,2%

Testing in the Command Prompt window after 10am: 

C:\Users\mharrison>set T=%time%

C:\Users\mharrison>echo %T%

10:11:54.96 

C:\Users\mharrison>set TT=%T:~1,1%%T:~3,2%%T:~6,2%%T:~1,1%%T:~3,2%%T:~6,2%

C:\Users\mharrison>echo %TT%

0115401154

C:\Users\mharrison>echo filename%TT%

filename0115401154