Don't know about theis particular model, but most Flymo's are adjusted by inserting of removing spacers under the blade. These are an easily available and cheap spare part - you should have got some with your mower. If you didn't, I have a pile of them (assuming they are the same as other Flymos). They are basically a thick plastic washer with locating 'pips' on one side, and holes on the other.
phil_saunders(a)bigfoot.com
Phil Saunders, June 2012
