I know on linux box, one can use the command split to break files specifying how many megabytes you want like split -b 1024m file_name, then use the command cat to assemble them together, like cat bfile* > file_name
I know it has been used for several file types.
I don't know if that is what you are looking for or if windows has something similar to these.
Using man split and man cat show it's usage.
If you tell me, I'll forget.
If you show me, I'll remember.
if you involve me, I'll understand.
--- Author unknown to me