Thanks for all the pointers. The rattle gun wasn�t an option as the bolt head was far too indented into the blade plate because the previous owner obviously forgot to put a washer and lock washer before tightening the bolt. Thanks for the tip of using the standard socket. I�ll keep that in the memory bank for next time, noting of course the potential safety concerns.

I ended up going with Mark and Grumpys suggestion. It took some careful grinding to keep a nice hexagon. After about 10 minutes of careful grinding and then re-testing with a 13mm socket the bolt came out relatively easily. The trick in this case was grumpy�s suggestion to cut into the blade plate (which was already damaged) and allow the compelte bolt head to be gripped with the 13 mm socket.

I had to grip the boss with a set of multigrips because it was spinning in the absences of the 3 snapped bolts.

I ended up putting on a round plate plate with four blades for that nicer cut. I also had to replace the boss because of the broken bolts. I have a couple of second hand bosses off wrecked mowers so it wasn�t a problem. I have included a couple of photos below.

Thanks again for all your help

Peter

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