Aye, re-watched the vid a few days ago and realised a little something sticking out will fix that easily enough. Will probably just weld a bit of bolt on with the end ground down to a spike, but haven't got round to it yet as Carcinus currently needs some considerable re-jigging and I've been giving the MDF bot some attention. I'm on holiday from work from this Friday right through until the Monday after the champs so I'll get on it then :)