External Mechanical Impact

So in the repair cafe, I landed another impossible task.  It was a 240V mains hedge trimmer.  The most typical problem is broken wire, it wasn't.  Everything was held by each other within the plastic hub, so once it was undone, it was impossible to put back together... And a floor full of grease...

But I did find out what was wrong with it.  The carbon brush was worn, not making contact...  So in hind sight, it needed an external impact to help the brushes be seated, a good old wack!