lace shawl

The lace shawl is still continuing on , its taking a very long time to knit but i am going to change the cast off as i dont want it to be frilly like in the pattern.
just yesterday i reached the mark of having to increase from 512 to 1024 stitches meaning i will have to buy another ball of wool to finish the project.
I am now working on my own pattern because i decided to make the shawl out of lace weight,( im not fond of dk or aran weight shawls as the pattern suggested i think they look bulky)i knew that when in the pattern you would cast off i would still have to go on further ive allready added 40 more rows but believe i may have to add another 40 more to finish the piece.
Having just knitted the last 4 rows i have totally run out of yarn i think im going to need one or even 2 more balls of the lace weight noro wool.