------- Create base data -------------------------------------------
IF OBJECT_ID('tempdb..#OrigTable') IS NOT NULL DROP TABLE #OrigTable
CREATE TABLE #OrigTable (ID INT , LongString VarChar(MAX))

DECLARE @x INT, @s VarChar(Max)
SET @x = 1
SET @s = 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. '

WHILE LEN(@s) < 3000000
BEGIN
     SET @s = @s + @s
END

WHILE @x <= 5
BEGIN 
     INSERT INTO #OrigTable Values (@x,@s)
     SET @x = @x + 1
END

-------Split the original into useable chunks--------------------------

IF OBJECT_ID('tempdb..#SplitTable') IS NOT NULL DROP TABLE #SplitTable
CREATE TABLE #SplitTable (ID INT , StringPart INT, LongString VarChar(MAX))

DECLARE @id INT, @sp INT, @ls VarChar(MAX)
SET @id = 1
SET @sp = 1

WHILE @id <= (SELECT MAX(ID) FROM #OrigTable)
BEGIN
     SET @ls = (SELECT LongString FROM #OrigTable WHERE ID = @id)
     WHILE LEN(@ls) > 0
     BEGIN
          INSERT INTO #SplitTable Values(@id, @sp, LEFT(@ls, 64000))
          SET @ls = (SELECT CASE WHEN LEN(@ls) < 64000 THEN '' ELSE RIGHT(@ls, LEN(@ls) - 64000) END)
          SET @sp = @sp + 1
     END
     SET @sp = 1
     SET @id = @id + 1
END

SELECT * FROM #SplitTable