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Author Message   Glenn Middleton Rating: N/A Votes: 0 Posted on Friday, October 14, 2005 - 08:15 pm:    If left-hand drill bits are not available you can make miniature spade bits from silver-steel rod.Grind/file the relief for anti-clock rotation and then harden right out.Polish and temper to a light straw colour.Drill out using a slow speed and light feed.These will also pick up/catch in many instances,unscrewing the stub in the process. The advantage of a spade bit, when filed up properly,is the less risk of damaging the threads when the bit is not parallel with the tapped hole.This is because the spade bit will only have it's cutting edge on the end.The flute edges on a twist bit can damage the wall of the hole if not parallel to same. Here in the UK left hand drill bits in small sizes ie 1.5mm to 3mm are not that readily available,except from specialised dealers.So the spade bit is usually the simplest way out of the problem.