Had to replace the wiper on the Aygo last night. Noticed it wasn't wiping the whole window. Checked it, looked OK. So, deciding to finally get a new blade from
Halfords, as I was due to pass the store, checked again, and the whole arm flopped down. Oh. The arm is only plastic and had split. So, onto
ebay, less than £8 for a new arm and blade. It was £8 in Halfords for a blade.
The retaining nut was on tight so that took a big spanner, to be met with the captive nut that's usually on the arm having corroded onto the spindle. Out with the Dremel and cut it off, new arm and blade fitted.