I also used a specialized tally table (starting with 0 and steps of 3) and came up with a simpler approach.  (I thought that using a 0-base was more obvious than using a 1-base when incrementing by three, so I used that even though it made the formulas a little more complicated.)


SELECT Column1, STUFF(ss,1, 1, '')
FROM MyTable mt
CROSS APPLY
(
    SELECT '|' + SUBSTRING(mt.Column1, n + 1, 3)
    FROM ( VALUES(0), (3), (6), (9), (12), (15), (18), (21), (24) ) Tally(n)
    WHERE SUBSTRING(mt.Column1, n + 1, 3) > '000'
    ORDER BY n
    FOR XML PATH('')
) v(ss)


Drew

Edit: I didn't feel like entering the entire tally table, so you'll need to fill it out to 57.