Before you attempt to remove any broken bolt there are a couple of gearbox motor frame bracket things that you can do that can make it easier. One of the first things you should do is try to shock it now I'm actually going to use a spring-loaded punch to do this, so I'm just going to give that a few gentle taps. If you don't have a spring-loaded punch like that you can use a traditional punch just give that a few gentle taps with a club hammer and that can help to free the broken bolt. Can also apply some heat obviously you have to be careful， if you're using burning gear because you can quite easily melt the aluminium.

   You can also use some spray penetrant and gearbox motor frame bracketthere are the good chance that will help. One thing that you could use is a hinge sighting drill they have a spring loaded part there which exposes the drill bit that will actually prevent the drill bits from catching the side of the material which you are trying to remove the broken bolt from. In sighting drills are normally used like that, you'll position your hinge where you want it then you can simply use that to drill your pilot holes that will ensure they are dead central. However I'm not going to use it for that I'm going to use that to ensure that I can drill dead in the center of a sheared bolt.

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   So if we try that in the end of the shaft you can see that it's a very good fit and we're not going to actually damage the gearbox motor frame bracketon that. You can of course use a regular right handed drill in a hinge sighting drill but that will then mean that you will need to use a screw extractor afterwards. So I'm now going to flick the drill in to reverse and then we're going So you can see that the left handed drill bit actually started to bite into that and it actually extracted it from the hole.